IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Analysis of dual bell rocket nozzle using computational fluid dynamicseSAT Journals
Abstract Concept of Altitude adaptive rocket nozzles recently received greater importance and interest in the space explorations and other such applications in space and rocket technology. The operations reliability of rocket launcher and the earth to orbit rocket launch are the crucial for the space transportation in the future. The performance of the engine components such as the power plant and the thrust delivery of the engine such as nozzles are in renovation for the greater performance and applicability for complex space applications. In the recent progress of the combustion expansion system the rocket nozzles are greatly revised from both application and design perspectives. One of such development is the dual bell nozzle. The publications indicate that the research on the concept of dual bell nozzle is tardy and there is no much progress from the inception of the idea. The specific application purpose designs are tested experimentally and implemented but the large scale development can only be possible if the generalized design parameters can be suggested. In the present paper one of such nozzle is selected and studied using computational fluid dynamics (CFD) and the results are synthesized for bench marking the general approach to study the Dual Bell nozzles. The result shows the variation in the Mach number, pressure, temperature distribution and turbulence intensity. Keywords: Altitude adaptation, Dual bell nozzle, Nozzle pressure ratio, Over-expansion factor.
Numerical simulation and optimization of high performance supersonic nozzle a...eSAT Journals
Abstract The Principle purpose of a nozzle is to accelerate the flow to higher exit velocities. The fluid acceleration is based on the design criteria and characteristics. To achieve good performance characteristics with minimum energy losses a nozzle must satisfy all the design requirements at all operating conditions. This is possible only when the nozzle theory is assumed to be isentropic irrespective of the changes in pressure, temperature and density which is generally caused due to formation of a Shock Wave. The thesis focuses on the design, development and optimization of a Supersonic Convergent-Divergent Nozzle where the analytical results are validated using theory calculations. The simulation work is carried out for CD Nozzles with different angles of divergence keeping the other inputs fixed. The objective of the proposed thesis is to show the best Expansion ratio, Nozzle Pressure ratio (NPR) and Nozzle Area Ratio(NAR) where the thrust obtained by the supersonic nozzle is maximum. The simulation is then repeated for expansion gas the results of which are later compared with standard air to show which possesses better performance characteristics. The Nozzle design chosen is based upon existing literature studies. Key Words: CD Nozzle, Expansion Ratio, Nozzle Pressure Ratio (NPR), Nozzle Area Ratio(NAR),Divergence Angle etc…
Numerical assessment of the backward facing steps nozzleeSAT Journals
Abstract The backward facing steps nozzle (BFSN) is a flow adjustable exit area nozzle for large rocket engines. It consists of two parts, the first is a base nozzle with small area ratio and the second part is a nozzle extension with surface consists of backward facing steps. The number of steps and their heights are carefully chosen to produce controlled flow separation at steps edges that adjust the nozzle exit area at all altitudes (pressure ratios). The BFSN performance parameters are assessed in terms of thrust and side loads against the dual-bell nozzle (DBN) with the same pressure ratios and cross sectional areas. The DBN is a two-mode flow adjustable exit area nozzle for low and high altitude. Three-dimensional turbulent flow solutions are obtained for the BFSN indicating that the flow is axi-symmetric and does not generate significant side loads. Further confirmation of the axi-symmetric flow is obtained by comparing the three-dimensional flow with the two-dimensional axi-symmetric solutions. The comparison of the thrust generated over the PR range from 50 to 1500 shows that BFSN generates more uniform and higher thrust than the DBN in the intermediate pressure ratios. At PR 1500 (high altitude), the BFSN thrust is 0.28% less than the DBN. All numerical solutions are obtained using the Fluent code. Keywords: Backward facing steps nozzle, Turbulent flow in supersonic nozzle, Side load in supersonic nozzle.
5 ijreh feb-2018-1-aerodynamically study by mathematicalAI Publications
The flow field and mixing characters of high efficiency vortices in one type of Radially Stratified Flame Core Burner RSFC where analysed through Cold computing fluid dynamics model CFD in accordance with Mathematical model for flame visualization. The model gives good results and clears the important aerodynamics features of a typical low Nitrogen Oxides NOx of internal staging schematic. The model can be used to evaluate this design performance or to get the necessary information for development its efficiency in accordance with the global demand to clean energy with high efficiency and low NOx emissions. The mixing of this burner dominated by coherent structures, so it is outperform the molecular diffusivity and the length which fluids will mix is independent of the fluid velocity and can determined only from Taylor macroscale which related by the physical size of the fluid domain or in better understanding with the internal recirculating zone dimensions because it is form a region for axial mixing for species and smear out their residence time distribution.
Evaluation of Modelling of Flow in Fracturesidescitation
Heat-transport is important for geothermal exploration. The presence of
fractures can have a pronounced effect on groundwater and heat transfer.The inclusion of
fractures into geothermal reservoir models on different scales is often still a difficult task. A
comparison of approaches for flow in fractures has been carried out. A very simple
approach is to simulate fractures with thin but highly conductive layers, for instance by
applying the Cubic-Law. A more sophisticated approach, typically in FEM codes, is the
application of lower dimensional (1D/2D) high permeable discrete elements with specific
flow properties, following e.g. Hagen-Poiseuille or Manning-Strickler. However, such an
approach typically fails while studying only partly saturated fractures. For studying the
applicability of simplified fracture modellingapproaches a comparison with a CFD
(Computational Fluid Dynamics) solution was performed. Furthermore a DEM (Discrete
Element Method)approach has been illuminated. The various methodologies are studied by
varying roughnesses,this way studying the versatility of the approach. The sensitivity of
flow in fractures to various numerical parameters can be studied this way. A detailed
analysis of temperature and flow using Péclet and Reynolds numbers helps to quantify the
contributions of the different transfer processes.
Analysis of dual bell rocket nozzle using computational fluid dynamicseSAT Journals
Abstract Concept of Altitude adaptive rocket nozzles recently received greater importance and interest in the space explorations and other such applications in space and rocket technology. The operations reliability of rocket launcher and the earth to orbit rocket launch are the crucial for the space transportation in the future. The performance of the engine components such as the power plant and the thrust delivery of the engine such as nozzles are in renovation for the greater performance and applicability for complex space applications. In the recent progress of the combustion expansion system the rocket nozzles are greatly revised from both application and design perspectives. One of such development is the dual bell nozzle. The publications indicate that the research on the concept of dual bell nozzle is tardy and there is no much progress from the inception of the idea. The specific application purpose designs are tested experimentally and implemented but the large scale development can only be possible if the generalized design parameters can be suggested. In the present paper one of such nozzle is selected and studied using computational fluid dynamics (CFD) and the results are synthesized for bench marking the general approach to study the Dual Bell nozzles. The result shows the variation in the Mach number, pressure, temperature distribution and turbulence intensity. Keywords: Altitude adaptation, Dual bell nozzle, Nozzle pressure ratio, Over-expansion factor.
Numerical simulation and optimization of high performance supersonic nozzle a...eSAT Journals
Abstract The Principle purpose of a nozzle is to accelerate the flow to higher exit velocities. The fluid acceleration is based on the design criteria and characteristics. To achieve good performance characteristics with minimum energy losses a nozzle must satisfy all the design requirements at all operating conditions. This is possible only when the nozzle theory is assumed to be isentropic irrespective of the changes in pressure, temperature and density which is generally caused due to formation of a Shock Wave. The thesis focuses on the design, development and optimization of a Supersonic Convergent-Divergent Nozzle where the analytical results are validated using theory calculations. The simulation work is carried out for CD Nozzles with different angles of divergence keeping the other inputs fixed. The objective of the proposed thesis is to show the best Expansion ratio, Nozzle Pressure ratio (NPR) and Nozzle Area Ratio(NAR) where the thrust obtained by the supersonic nozzle is maximum. The simulation is then repeated for expansion gas the results of which are later compared with standard air to show which possesses better performance characteristics. The Nozzle design chosen is based upon existing literature studies. Key Words: CD Nozzle, Expansion Ratio, Nozzle Pressure Ratio (NPR), Nozzle Area Ratio(NAR),Divergence Angle etc…
Numerical assessment of the backward facing steps nozzleeSAT Journals
Abstract The backward facing steps nozzle (BFSN) is a flow adjustable exit area nozzle for large rocket engines. It consists of two parts, the first is a base nozzle with small area ratio and the second part is a nozzle extension with surface consists of backward facing steps. The number of steps and their heights are carefully chosen to produce controlled flow separation at steps edges that adjust the nozzle exit area at all altitudes (pressure ratios). The BFSN performance parameters are assessed in terms of thrust and side loads against the dual-bell nozzle (DBN) with the same pressure ratios and cross sectional areas. The DBN is a two-mode flow adjustable exit area nozzle for low and high altitude. Three-dimensional turbulent flow solutions are obtained for the BFSN indicating that the flow is axi-symmetric and does not generate significant side loads. Further confirmation of the axi-symmetric flow is obtained by comparing the three-dimensional flow with the two-dimensional axi-symmetric solutions. The comparison of the thrust generated over the PR range from 50 to 1500 shows that BFSN generates more uniform and higher thrust than the DBN in the intermediate pressure ratios. At PR 1500 (high altitude), the BFSN thrust is 0.28% less than the DBN. All numerical solutions are obtained using the Fluent code. Keywords: Backward facing steps nozzle, Turbulent flow in supersonic nozzle, Side load in supersonic nozzle.
5 ijreh feb-2018-1-aerodynamically study by mathematicalAI Publications
The flow field and mixing characters of high efficiency vortices in one type of Radially Stratified Flame Core Burner RSFC where analysed through Cold computing fluid dynamics model CFD in accordance with Mathematical model for flame visualization. The model gives good results and clears the important aerodynamics features of a typical low Nitrogen Oxides NOx of internal staging schematic. The model can be used to evaluate this design performance or to get the necessary information for development its efficiency in accordance with the global demand to clean energy with high efficiency and low NOx emissions. The mixing of this burner dominated by coherent structures, so it is outperform the molecular diffusivity and the length which fluids will mix is independent of the fluid velocity and can determined only from Taylor macroscale which related by the physical size of the fluid domain or in better understanding with the internal recirculating zone dimensions because it is form a region for axial mixing for species and smear out their residence time distribution.
Evaluation of Modelling of Flow in Fracturesidescitation
Heat-transport is important for geothermal exploration. The presence of
fractures can have a pronounced effect on groundwater and heat transfer.The inclusion of
fractures into geothermal reservoir models on different scales is often still a difficult task. A
comparison of approaches for flow in fractures has been carried out. A very simple
approach is to simulate fractures with thin but highly conductive layers, for instance by
applying the Cubic-Law. A more sophisticated approach, typically in FEM codes, is the
application of lower dimensional (1D/2D) high permeable discrete elements with specific
flow properties, following e.g. Hagen-Poiseuille or Manning-Strickler. However, such an
approach typically fails while studying only partly saturated fractures. For studying the
applicability of simplified fracture modellingapproaches a comparison with a CFD
(Computational Fluid Dynamics) solution was performed. Furthermore a DEM (Discrete
Element Method)approach has been illuminated. The various methodologies are studied by
varying roughnesses,this way studying the versatility of the approach. The sensitivity of
flow in fractures to various numerical parameters can be studied this way. A detailed
analysis of temperature and flow using Péclet and Reynolds numbers helps to quantify the
contributions of the different transfer processes.
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This is my first crack at writing a technical report for an assignment in a mechanical engineering course at the University of Alberta. How was the clarity? Any feedback on how I can improve?
Analysis of Ground Effect on a Symmetrical AirfoilIJERA Editor
A Detailed Study and Computational Fluid Dynamics investigation was conducted to ascertain and highlight the
different ways in which ground effect phenomena are present around a symmetrical aerofoil-NACA 0015- when
in close proximity to the ground. The trends in force and flow field behaviour were observed at various ground
clearances, for different angle of attack. The analysis was carried out by varying the angle of attack from 00 to
100 and ground clearance of the trailing edge from minimum possible value to one chord length. It was found
that high values of pressure coefficient are obtained on the lower surface when the airfoil is close to the ground.
This region of high pressure extended almost over the entire lower surface for higher angles of attack. As a
result, higher values of lift coefficient are obtained when the airfoil is close to the ground. The flow accelerates
over the airfoil due to flow diversion from the lower side and higher mean velocity is observed near the suction
peak location. The pressure distribution on the upper surface did not change significantly with ground clearance
for higher angles of attack. The lift was found to drop at lower angles of attack at some values of ground
clearance due to suction effect on the lower surface as the result of formation of a convergent–divergent passage
between the airfoil and the ground plate. The values of drag coefficient were also noted for different ground
clearance, which is found to be decreasing as the airfoil is approaching to a closer ground clearance. This ground
effect is analyzed using FLUENT 5/6 code.
Brimmed diffuser is collection�acceleration device which shrouds a wind turbine.For a given turbine di ameter,the power augmentation can be achieved by brimmed diffuser,p opularly known as wind lens. The present numerical investigation deals with the effect of low pressure region created by wind l ens and hence to analyze the strong vortices formed by a brim attached to the shroud diffuser at exit. Also in this analysis,a c omparative numerical prediction of mass flow rates through the wind turbine has been carried out with various types of wind lens wh ich in turn helps to optimize the torque augmentati on. It has been numerically proved that there is significant increase in the wa ke formation & vortex strength when brimming effect is added to a diffuser
Thermal analysis of water cooled charge air cooler in turbo charged diesel en...eSAT Journals
Abstract
Air-cooled and water-cooled charge air coolers are used as applications in automobiles. The cooling media include engine’s
coolant, ambient air or any other external coolant source. Charge air cooler with offset strip fin geometry is chosen on both hot
and cold sides with fin thickness 0.15 mm, length 3.2 mm, height 5.2 mm and frequency of 18 fins per inch. The flow rate on hot
side is taken as 0.3 kg/s and cold side as 2 kg/s for air-cooled charge air cooler and for water-cooled charge air cooler on hot
side it is 0.3 kg/s and cold side is 0.265 kg/s with inlet temperature on hot side 160 oC and cold side 40 oC. With the above
conditions, performance evaluation is done on both charge air coolers. Having found water-cooled charge air cooler is having
higher effectiveness than air-cooled type, performance evaluation is carried out on water-cooled charge air cooler with varying
mass flow rates on hot side from 0.1 to 0.6 kg/s and keeping cold fluid rate constant at 0.265 kg/s and the outputs obtained are
Colburn-j factor, Fanning friction factor, heat transfer coefficient, overall heat transfer coefficient and effectiveness of heat
exchanger. From the obtained results, graphs are drawn to assess the performance of the water charge air cooler.
Keywords: Charge Air Cooler, Plate Fin Heat Exchanger, Colburn-J Factor, Heat Transfer Coefficient, Fanning
Friction Factor, Effectiveness
Calculation of Fluid Dynamic for Wind Flow around Reinforced Concrete WallsIJERA Editor
A study on the flow phenomena around free-standing walls is important in practical building construction. In the present paper a numerical study is conducted for two- dimensional incompressible steady flow around freestanding walls using low-Re k-co turbulence model. The separation regions downstream the wall and on the roof of the leeward were predicted. Finally, results of numerical simulation are presented in the form of velocity vectors, velocity contour, pressure contours and streamlines
Parametric Study for Wind Design of Vertical Pressure Vessel as per Indian St...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
A continuous time adc and digital signal processing system for smart dust and...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This is my first crack at writing a technical report for an assignment in a mechanical engineering course at the University of Alberta. How was the clarity? Any feedback on how I can improve?
Analysis of Ground Effect on a Symmetrical AirfoilIJERA Editor
A Detailed Study and Computational Fluid Dynamics investigation was conducted to ascertain and highlight the
different ways in which ground effect phenomena are present around a symmetrical aerofoil-NACA 0015- when
in close proximity to the ground. The trends in force and flow field behaviour were observed at various ground
clearances, for different angle of attack. The analysis was carried out by varying the angle of attack from 00 to
100 and ground clearance of the trailing edge from minimum possible value to one chord length. It was found
that high values of pressure coefficient are obtained on the lower surface when the airfoil is close to the ground.
This region of high pressure extended almost over the entire lower surface for higher angles of attack. As a
result, higher values of lift coefficient are obtained when the airfoil is close to the ground. The flow accelerates
over the airfoil due to flow diversion from the lower side and higher mean velocity is observed near the suction
peak location. The pressure distribution on the upper surface did not change significantly with ground clearance
for higher angles of attack. The lift was found to drop at lower angles of attack at some values of ground
clearance due to suction effect on the lower surface as the result of formation of a convergent–divergent passage
between the airfoil and the ground plate. The values of drag coefficient were also noted for different ground
clearance, which is found to be decreasing as the airfoil is approaching to a closer ground clearance. This ground
effect is analyzed using FLUENT 5/6 code.
Brimmed diffuser is collection�acceleration device which shrouds a wind turbine.For a given turbine di ameter,the power augmentation can be achieved by brimmed diffuser,p opularly known as wind lens. The present numerical investigation deals with the effect of low pressure region created by wind l ens and hence to analyze the strong vortices formed by a brim attached to the shroud diffuser at exit. Also in this analysis,a c omparative numerical prediction of mass flow rates through the wind turbine has been carried out with various types of wind lens wh ich in turn helps to optimize the torque augmentati on. It has been numerically proved that there is significant increase in the wa ke formation & vortex strength when brimming effect is added to a diffuser
Thermal analysis of water cooled charge air cooler in turbo charged diesel en...eSAT Journals
Abstract
Air-cooled and water-cooled charge air coolers are used as applications in automobiles. The cooling media include engine’s
coolant, ambient air or any other external coolant source. Charge air cooler with offset strip fin geometry is chosen on both hot
and cold sides with fin thickness 0.15 mm, length 3.2 mm, height 5.2 mm and frequency of 18 fins per inch. The flow rate on hot
side is taken as 0.3 kg/s and cold side as 2 kg/s for air-cooled charge air cooler and for water-cooled charge air cooler on hot
side it is 0.3 kg/s and cold side is 0.265 kg/s with inlet temperature on hot side 160 oC and cold side 40 oC. With the above
conditions, performance evaluation is done on both charge air coolers. Having found water-cooled charge air cooler is having
higher effectiveness than air-cooled type, performance evaluation is carried out on water-cooled charge air cooler with varying
mass flow rates on hot side from 0.1 to 0.6 kg/s and keeping cold fluid rate constant at 0.265 kg/s and the outputs obtained are
Colburn-j factor, Fanning friction factor, heat transfer coefficient, overall heat transfer coefficient and effectiveness of heat
exchanger. From the obtained results, graphs are drawn to assess the performance of the water charge air cooler.
Keywords: Charge Air Cooler, Plate Fin Heat Exchanger, Colburn-J Factor, Heat Transfer Coefficient, Fanning
Friction Factor, Effectiveness
Calculation of Fluid Dynamic for Wind Flow around Reinforced Concrete WallsIJERA Editor
A study on the flow phenomena around free-standing walls is important in practical building construction. In the present paper a numerical study is conducted for two- dimensional incompressible steady flow around freestanding walls using low-Re k-co turbulence model. The separation regions downstream the wall and on the roof of the leeward were predicted. Finally, results of numerical simulation are presented in the form of velocity vectors, velocity contour, pressure contours and streamlines
Parametric Study for Wind Design of Vertical Pressure Vessel as per Indian St...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
A continuous time adc and digital signal processing system for smart dust and...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Study and comparative analysis of resonat frequency for microsrtip fractal an...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
A 2.4 ghz cmos lna input matching design using resistive feedback topology in...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Analysis of multi hop relay algorithm for efficient broadcasting in manetseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A simulation study of wi max based communication system using deliberately cl...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Smfir technology based transportation system and applicability of mppteSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Ultrasonic study of some amino acids in aqueous salt solution of kno3 at 303....eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Technical engineering in industrial ippc as a key tool for ambient air qualit...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Passive control of structures using sliding isolators at intermediate floor l...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Design and flow simulation of truncated aerospike nozzleeSAT Journals
Abstract Aerospike nozzles are being considered in the development of the Single Stage to Orbit launching vehicles because of their prominent features and altitude compensating characteristics. This paper presents the design of aerospike nozzles using characteristic method in conjunction with streamline function, and performance study through numerical simulation using commercial Computational Fluid Dynamics (CFD) code ANSYS FLUENT. For this purpose nozzles with truncation lengths of 25%, 40%, 50% are choosen, because of the thermal and structural complications in the ideal aerospike nozzle. Simulation of the flow is carried out at three different altitude conditions representing Under-expansion, Ideal, and over-expansion conditions of the flow. FLUENT predictions were used to verify the isentropic flow assumption and that the working fluid reached the design exit Mach number. The flow-fields obtained through the numerical simulation are analysed to know the effect of truncation on the performance of aerospike nozzle. Optimum percentage of the truncation is selected by the comparison of nozzles with different lengths of truncation under various altitude parameters. The results show that the flow pattern of the nozzles under different altitude conditions are almost similar. The 40 % truncated nozzle is found to give optimum performance and it has achieved the desired exit Mach number in all the three altitude conditions. Keywords: Aerospike Nozzle, Single Stage to Orbit (SSTO), Linear Aerospike, Truncation and Rocket Nozzle
Effect of spikes integrated to airfoil at supersonic speedeSAT Journals
Abstract
The objective of this is to analyse the flow field over an aerofoil section integrated with spikes at supersonic speed (Mach number
greater than 1). Use of spike integrated with aerofoil changes the flow characteristics over aerofoil and hence aerodynamic lift
and drag. The experiment consists of flow visualization graphs and measurement of coefficient of aerodynamic drag and lift.
Here we are using different shapes of spike like sharp edge and hemi spherical edge. In this we will compare the flow over
aerofoil with spike and without spike. The flow analysis is done by using Computational fluid dynamics (CFD). CFD is the study
of external flow over a body or internal flow through the body. CFD is aiding aero-dynamist to better understand the flow physics
and in turn to design efficient models. In short, CFD is playing a strong role as a design tool as well as a research tool.
Keywords: NACA 651-412 airfoil, spike, Ansys Fluent, Ansys ICEM CFD, Pressure Coefficient
Diffusers are extensively used in centrifugal
compressors, axial flow compressors, ram jets, combustion
chambers, inlet portions of jet engines and etc. A small change in
pressure recovery can increases the efficiency significantly.
Therefore diffusers are absolutely essential for good turbo
machinery performance. The geometric limitations in aircraft
applications where the diffusers need to be specially designed so
as to achieve maximum pressure recovery and avoiding flow
separation.
The study behind the investigation of flow separation in a planar
diffuser by varying the diffuser taper angle for axisymmetric
expansion. Numerical solution of 2D axisymmetric diffuser model
is validated for skin friction coefficient and pressure coefficient
along upper and bottom wall surfaces with the experimental
results of planar diffuser predicted by Vance Dippold and
Nicholas J. Georgiadis in NASA research center [2]
.
Further the diffuser taper angle is varied for other different
angles and results shows the effect of flow separation were it is
reduces i.e., for what angle and at which angle it is just avoided.
Development of Software for Sizing of Axial Flow Fans -- Zeus NumerixAbhishek Jain
Above Research Paper can be downloaded from www.zeusnumerix.com
The research paper aims to showcase the development of software for the aerodynamic design of cooling tower fans. The software inputs requirements from the user and outputs the 3D CAD of an optimized fan. The software calculates power consumption, efficiency, torque, and sound level of the fan. The software has been found to overpredict the performance by few percentage points due to uncertainty in manufacturing. Authors - Abhishek Jain (Zeus Numerix), Ketan Bhokray (IIT Bombay)
Experimental study of heat transfer and hydrodynamics of falling film on a no...eSAT Journals
Abstract
An improved evaporator with helical finned tube falling film is presented. Its technology of building is simple and it is a question
of piling plates in two wings, identical and simple forms, by respecting a regular gap between them to get the densely populated
double helical finned tube of walk of staircase. This new evaporator design introduces advantages to have two helical fins taken
up in parallel allowing doubling its area of exchange, a helical geometry allowing influencing flow favorably for a good
distribution of the film and a strong density of walk of staircase playing promoters turbulence role that can improve its heat
transfer coefficient side film. Thermal study, in heating, evaporating and convective boiling regimes, allowed showing, on the
basis of the criterion of the thermal height unit, HTU, a better performance compared with mono-finned evaporators and the
smooth double helical finned tube without walk of staircase of the same density.
Keywords - helical evaporator, falling film, double fins, density of walk of staircase, HTU
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Wind energy is a promising energy source. Modern wind power industry officially started in 1979 in Denmark with a
turbine of few KW and its evaluation brought up to now, devices of which rated power is higher than 20 MW.
The size of wind turbine’s massively increased and their design achieved a common standard device: Horizontal axis,
Three blades, Upwind, Pitch controlled blades, Active yaw system.
This paper deals with the numerical analysis of 3d model which has inlet port diameter 46mm,valve diameter 43mm and the length and diameter of the cy linder is 562mm and 93.65mm respectively which is developed to study the effect of valve lif t on the flow of fluid inside the cylinder. For different valve lifts velocity will change inside t he cylinder. Results of CFD simulation indicated th at valve lift affects velocity flow field inside the c ylinder. It also proved that CFD is a convenient to ol for designing and optimizing the flow field in the engine.
Experimental investigation of stepped aerofoil using propeller test rigeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Cfd analysis of rae 2822 supercritical airfoil at transonic mach speedseSAT Journals
Abstract The Aerodynamic characteristics of an airfoil play a very important role in terms of design aspects and experimental validation. A distinctive supercritical airfoil is found to give inappropriate results at peak operating conditions. This led to design changes and optimization of the foil with the help of a cusp like structure added to the trailing edge of the foil. The present work emphasizes the computation of a supercritical airfoil with and without wedge profiles at different angles of attack and free stream velocities. The formation of a shock wave is observed when the free stream approaches a transonic mach number. This shock wave is a type of propagating disturbance which greatly effects the aerodynamic performance of the airfoil. The flow properties such as pressure, temperature and density experience a drastic change upstream and downstream of the generated shock. The main goal of the proposed paper is to carryout the simulation and analysis of RAE 2822 supercritical airfoil with and without wedge profiles along with the study of aerodynamic characteristics such as Lift and drag coefficients at different Mach numbers. The objective is to improve the stability of the airfoil when the flow approaches transonic Mach speeds. The design profile chosen is based upon existing literature studies. Key Words: Supercritical Airfoil, Shock wave, Transonic mach, Mach number etc…
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 412
ANALYSIS OF DUAL BELL ROCKET NOZZLE USING
COMPUTATIONAL FLUID DYNAMICS
Balaji Krushna.P1
, P. SrinivasaRao2
, B. Balakrishna3
1
M.tech Student, 3
Professor, Mechanical Engineering, UCEK-JNTUK, AP, India
2
Professor, Mechanical Engineering, Vardhaman College of Engg.., AP, India
balajikrushna.p@gmail.com, er.p.srinivas@gmail.com, balakrishnajntu06@gmail.com
Abstract
Concept of Altitude adaptive rocket nozzles recently received greater importance and interest in the space explorations and other such
applications in space and rocket technology. The operations reliability of rocket launcher and the earth to orbit rocket launch are the
crucial for the space transportation in the future. The performance of the engine components such as the power plant and the thrust
delivery of the engine such as nozzles are in renovation for the greater performance and applicability for complex space applications.
In the recent progress of the combustion expansion system the rocket nozzles are greatly revised from both application and design
perspectives. One of such development is the dual bell nozzle. The publications indicate that the research on the concept of dual bell
nozzle is tardy and there is no much progress from the inception of the idea. The specific application purpose designs are tested
experimentally and implemented but the large scale development can only be possible if the generalized design parameters can be
suggested. In the present paper one of such nozzle is selected and studied using computational fluid dynamics (CFD) and the results
are synthesized for bench marking the general approach to study the Dual Bell nozzles.
The result shows the variation in the Mach number, pressure, temperature distribution and turbulence intensity.
Keywords: Altitude adaptation, Dual bell nozzle, Nozzle pressure ratio, Over-expansion factor.
-----------------------------------------------------------------------***-----------------------------------------------------------------------
1. INTRODUCTION
The most popular altitude-compensating rocket nozzle to date
is the Dual bell nozzle, the origin of which dates back to
Rocket dyne in the 1950s. This type of nozzle was designed to
allow for better overall performance than conventional nozzle
designs. This concept was thoroughly explored by the
Germans during the time of the world war where in they were
to be posted as a threat for their rivals. The structure of this
type of nozzle roots on its advantages of minimizing the losses
encountered in the previous versions of the conventional
types. The literature survey has been thoroughly studied and
their researches were beneficial.
A nozzle is used to give the direction to the gases coming out
of the combustion chamber. Nozzle is a tube with variable to
convert the thermo-chemical energy generated in the
combustion chamber into kinetic energy. The nozzle converts
the low velocity, high pressure, high temperature gas in the
combustion chamber into high velocity gas of lower pressure
and low temperature. Our study is carried using software’s
like Gambit 2.4 for designing of the nozzle and Fluent 6.3.2
for analyzing the flows in the nozzle.
In this paper CFD analysis of pressure and temperature for a
dual bell rocket nozzle is analyzed with the help of fluent
software. when the fuel and air enter in the combustion
chamber according to the x and y plot, it is burning due to
high velocity and temperature and then temperature increases
rapidly in combustion chamber and convergent part of the
nozzle and after that temperature decreases in the exit part of
the nozzle.
1.1 Need for New Nozzle Design
The revolution in aerospace propulsion was increased greatly
during World War 2. Faster, bigger and more efficient
aerospace vehicles were required which led to the birth of
Space research organizations like NASA. Speaking about the
future, advanced rocket propulsion systems will require
exhaust nozzles that perform efficiently over a wide range of
ambient operating conditions. Most nozzles either lack this
altitude compensating effect or they are extremely difficult to
manufacture. Bell nozzles are currently used for all aerospace
applications.
2. METHODOLOGY
A detailed study of concepts for the project is carried out. A
procedural theoretical approach of nozzles is carried out and
the models of nozzles namely the full length Dual-bell nozzle
created using Fluent, Gambit software. The next step goes to
2. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 413
the meshing and analysis of the dual bell model using
FLUENT software. The behavior of flow along the dual bell
nozzle is thus obtained and comparison on the basis of Mach
number is henceforth done using theoretical calculations.
The material is selected as air and the density as ideal gas to
make the solution simpler. Under the solve command the
control is selected for limiting the pressure to a maximum of
5e+7 and Minimum of 1e+4. The initialization of value is
computed from the inlet. It is also necessary to select the
appropriate approximation required in the residual command
under monitors and check in plot to visualize the progress of
iteration. Once every parameter is described the iteration is
performed till the value gets converged to required
approximation. The Figures can be plotted between position in
x-axis and any other function in y-axis from plot command or
else to view vectors, contours or grid display command is to
be chosen. A mathematical model consists of differential
equations that govern the behavior of the physical system, and
the associated boundary conditions.
3. DUAL BELL NOZZLE
The concept of nozzle was first studied at the Jet Propulsion
Laboratory in 1949. In the late 1960s, Rocket dyne patented
this nozzle concept, which has received attention in recent
years in the U.S. and Europe. Figure illustrates the design of
this nozzle concept with its typical inner base nozzle, the wall
inflection, and the outer nozzle extension. This nozzle concept
offers an altitude adaptation achieved only by nozzle wall
inflection. In low altitudes, controlled and symmetrical flow
separation occurs at this wall inflection Fig.2 which results in
a lower effective area ratio. For higher altitudes, the nozzle
flow is attached to the wall until the exit plane, and the full
geometrical area ratio is used. Because of the higher area ratio,
an improved vacuum performance is achieved. However,
additional performance losses are induced in dual-bell nozzles,
as compared with two baseline nozzles having the same area
ratio as the dual-bell nozzle at its wall inflection and in its exit
plane.
Flow transition behavior in dual-bell nozzles strongly depends
on the contour type of the nozzle extension. A sudden
transition from sea-level to vacuum operation can be, at least
theoretically, achieved by two different extensions, with a zero
wall pressure gradient (constant pressure extension), or a
positive wall pressure gradient (overturned extension). But a
critical analysis of the transition behavior considering
decreasing ambient pressures during the launcher ascent
revealed that a considerable time with uncontrolled flow
separation within the nozzle extension exists even for these
types of extensions. The duration of this period can be reduced
drastically by throttling the chamber pressure.
Fig .1 Sketch of a dual-bell nozzle
The main advantage of dual-bell nozzles as compared to other
means of controlling nozzle flow separation is its simplicity
because of the absence of any movable parts and, therefore, its
high reliability. It is necessary to note that the external flow
over the vehicle in flight reduces the pressure in the vehicle
base region, where engines are installed. The ambient pressure
triggering the flow transition is the vehicle base pressure
instead of the atmospheric pressure at the specific flight
altitude. As the base pressure is lower than the atmospheric
pressure, the nozzle flow transition occurs at a lower altitude
than the one showed in Fig.1 which slightly decreases the
efficiency of the dual-bell nozzle operation along the
trajectory. Despite the additional losses induced in dual-bell
nozzles, they still provide a significant net impulse gain over
the entire trajectory as compared to conventional bell nozzles.
Independent combined launcher and trajectory analyses
performed by Dasa within the European Space Agency Future
European Space Transportation Investigations Program (ESA
FESTIP) study and at DLR on SSTO vehicles powered with
dual-bell nozzles result in a significant payload gain when
compared with a reference launcher equipped with
conventional nozzles.
Fig.2 Dual-bell nozzle (a) low altitude (b) high altitude
3. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 414
Dual-bell nozzle designs accommodate several outlet
pressures and provide a significant net impulse gain over the
entire trajectory as compared to conventional bell nozzles. The
concept proposes a typical inner base nozzle accompanied by
an outer nozzle addition. The connecting point between radial
contours is a wall inflection point. Figure 3(a) shows that the
exhaust flow for lower altitude operation separates at the
inflection point whereas Fig. 3(b) Shows that higher altitude
flow remains attached until the exit plane of the outer nozzle
extension.
Fig 3 Flow field phenomena in dual-bell nozzles: a) sea-level
mode with flow separation at the wall inflection point and b)
altitude mode with a full- flowing nozzle.
For higher altitudes, the nozzle flow is attached to the wall
until the exit plane, and the full geometrical area ratio is used.
Because of the higher area ratio, an improved vacuum
performance is achieved. However, additional performance
losses are induced in dual-bell nozzles, as compared with two
baseline nozzles having the same area ratio as the dual-bell
nozzle at its wall inflection and in its exit plane. Below
Figures illustrate the performance of a dual bell nozzle as a
function of flight altitude in comparison with both baseline
bell-type nozzles.
3.1 Background:
In supersonic flow, the influence of a small pressure
disturbance is limited to a specific region.
Pressure disturbance propagates relative to fluid as a
spherical sound wave at local velocity of sound a.
Center of sound wave moves downstream with velocity
u.
Changes in fluid properties may be thought of as
propagating along Mach lines:
Mach line is straight, if flow upstream is uniform.
All properties of flow immediately downstream of a
Mach line are uniform.
( ) ( )
−
=
−
=
=
=
−−
−−
1
1
tantan
1
sinsin
2
1
22
1
11
Matut
at
Mut
at
α
α
Fig 4 Performance data of a dual-bell nozzle
Performance is compared with two baseline bell-type nozzles
as function of flight altitude (baseline nozzle 1: same area
ratio as dual-bell base nozzle; baseline nozzle 2: same area
ratio as nozzle extension)
Fig 5 Performance characteristics of a dual-bell nozzle
4. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 415
Performance is compared with two baseline bell-type nozzles
as function of flight altitude (baseline nozzle 1: same area
ratio as dual bell base nozzle; baseline nozzle 2: same area
ratio as nozzle extension).
Fig.6.Geometrical parameters of a dual bell nozzle
4. THEORETICAL APPROACH
The theoretical approach can be identified as the coresection
of the project whereas the efficiency analysisis carried out
with design parameters. Rocket nozzle efficiency,
ηC =
tcoefficienthrustIdeal
tcoefficienthrustActual
ηC=
Cthrust.i
Cthrust.a
Actual Thrust Coefficient =
tc.AP
Thrust
Thrust force is given by,
F= eae
K
1K
c
e
1-K
1K
2
C A)P-P(
P
P
1
1K
2
1-K
K2
P*A +
−
+
−+
5. DESIGN PARAMETERS
Design parameters Values
Throat Raidus Rth 15 mm
Exit area, ae 14.3 in2
Exit area ratio, ae/ab 4
Rocket flow specific heat ratio, γ 1.532
Nozzle exit mach number me 1.2
Rocket chamber pressure pc 3200 Psia
Nozzle exit pressure pe 3.41e+04 pasc
6. FLOW ANALYSIS
The flow analysis for the dual bell nozzle is carried out using
ANSYS 14.0 Fluent software. In this process first the models
are imported, meshed and flow analysis is carried out in major
three steps
1. The first step is GAMBIT, where the meshed model is
imported and boundaries are created and corresponding
boundary conditions are assigned to the boundaries.
2. The second step is FLUENT-SOLVER, where the solutions
are obtained by solving the equations and process is
highlighted in terms of codes and graphs and once the run is
over it reaches next step.
3. The third step is FLUENT, where the corresponding
contours are created for following major parameters such a
Pressure, Temperature and Mach number.
7. RESULTS AND DISCUSSION
7.1 Mach Number
The velocity magnitude is found to increase as move from
inlet to exit. The velocity at the inlet is 0.067Mach (sub-
sonic). At the throat section the velocity varies from 0.06
Mach to 0.08 Mach. The velocity at the exit is found to be
1.2Mach (super-sonic)
Fig.7 Contour of Mach number
5. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 416
7.2 Dynamic Pressure
Fig.8 Dynamic Pressure (Pascal)
Dynamic pressure is the pressure that is exerted by a fluid.
Specifically, it is the pressure measured when the fluid is still,
or at rest. The above figure reveals the fact that the gas gets
expanded in the nozzle exit. The Dynamic pressure in the inlet
is observed to be 5.41 e+04 Pa and as move towards the throat
there is a increase and the value at the throat is found out to be
7.22 e+04 Pa. After the throat, there is a sudden increase in the
Dynamic pressure at the axis which indicates the occurrence
of the shock. After the shock there is a slight decrease in the
pressure but it again rises at the second shock. Then it reduces
to a value of 3.16 e+04 Pa at the exit section due to the
expansion of the fluid towards the exit of the nozzle.
7.3 Static Pressure Graph
7.4 Velocity
Fig.9 Contours of Velocity Magnitude (m/s)
The velocity magnitude is found to increase as move from
inlet to exit. The velocity at the inlet is 1.22 e+02 m/s . At the
throat section the velocity varies from 2.40 e+02 m/s to 2.70
e+02 m/s . The velocity at the exit is found to be 3.29 e+02.
7.5 Radial Velocity
Fig.10 Contours of Radial Velocity (m/s)
The Radial velocity magnitude is found to increase as move
from inlet to exit. The velocity at the inlet is 2.29 e+01 m/s. At
the throat section the velocity varies from 1.34 e+02 m/s to
1.71 e+02 m/s . The velocity at the exit is found to be 2.81
e+02 m/s.
8. MERITS
The dual bell nozzle has 90% overall better performance than
the conventional bell-shaped nozzle. The efficiency at low
altitudes is much higher because the atmospheric pressure
restricts the expansion of the exhaust gas. A vehicle using a
dual bell nozzle also saves 25-30% more fuel at low altitudes.
At high altitudes, the dual bell nozzle is able to expand the
engine exhaust to a larger effective nozzle area ratio. The dual
bell design is suitable for Single Stage to Orbit (SSTO) flight.
Other advantages are that the dual bell nozzle makes better use
of the base area, and has higher thrust efficiency and thus a
higher average specific impulse.
CONCLUSIONS
The following observations were found in the Dual bell
nozzle
Mach number: The Mach number at the exit is found to be
1.2Mach (super-sonic).
Dynamic Pressure: The dynamic pressure value of 3.16 e+04
Pa at the exit section due to the expansion of the fluid towards
the exit of the nozzle. Here pressure value is decreases inlet to
exit area of nozzle.
Velocity: The velocity value of Nozzle increases inlet to exit
the velocity at the exit is found to be 3.29 e+02.
6. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 417
Radial Velocity: The Radial Velocity of bell nozzle increases
from inlet to exit at the exit is found to be 2.81 e+02 m/s.
REFERENCES
[1] Dumonov, G., Ponomaryov, N.B. and Voinov,
A.L.,(1997)``Dual-Bell Nozzles for Rocket Engines of
Launch Vehicle Upper Stages and Orbital Transfer
Vehicles,’’ AIAA Paper 97-3089, 33rd
AIAA/ASME/SAE/ASEE Joint Propulsion Conference
& Exhibit, USA, Luglio.
[2] Hagemann, G., Immich, H., Nguyen, T. V., and
Dumnov, G. E.,(1998)“Advanced Rocket Nozzles,”
Journal of Propulsion and Power, Vol. 14, No. 5,
September-October pp. 620–634.
[3] Frey, M. and Hageman, G.,(1999)``Critical Assesment
of Dual-Bell Nozzles,’’ Journal of Propulsion and
Power, Vol. 15, No.1, Jan.-Feb.
[4] Hagemann, G., Immich, H. and Preuss, A,( 3-6
December 2002,)``Advanced Nozzle Concepts for
Future Rocket EngineApplications’’, 4th International
Conference on Launcher Technology, Liege, Belgium.
BIOGRAPHIES
Balaji krushna .P M.tech (CAD/CAM) UCEK-
JNTU Kakinada
Dr. P. Srinivas rao Ph.D. Professor and Head,
Dept of Aerospace Engineering Vardhaman
College of Engineering Hyderabad
Dr. B. Balakrishna Ph.D. Professor in
Mechanical Engineering & Head, Dept. of
Petroleum Engineering & Petrochemical Engg,
UCEK–JNTU Kakinada