This document summarizes an aerothermodynamic study of a generic flap configuration with an open gap conducted by researchers at the German Aerospace Center. The study used computational fluid dynamics simulations and experiments in a high enthalpy shock tunnel to better understand flap efficiency and heating effects. Experiments were performed using the shock tunnel at Mach numbers representative of the planned re-entry trajectory of the EXPERT spacecraft. Pressure and temperature measurements on the flap and body surfaces were taken to validate the CFD simulations.
The document summarizes modifications made to a two-stage centrifugal compressor to convert it into a single-stage compressor suitable for laboratory testing. Key modifications included replacing the refrigerant fluid with air, installing an external drive motor instead of the internal hermetic motor, and adding static pressure taps to the vaneless diffuser and volute casing. Experimental results showed the compressor was operating off-design, with the vaneless diffuser and volute being too large for the mass flow rates tested. Pressure maps revealed distortion in the diffuser and volute due to the tongue region, reducing stage performance.
This document discusses nozzles and provides objectives and information about different types of nozzles. It defines nozzles and diffusers, describes convergent and convergent-divergent nozzle shapes. It also defines critical pressure ratio and maximum mass flow, and provides equations to calculate properties like area, temperature, and velocity at different points in a nozzle. An example calculation is provided to demonstrate determining the throat and exit areas of a convergent-divergent nozzle.
This document provides an overview of drilling equipment used on oil rigs. It discusses various components of the rig including rig pumps, solids control equipment, air drilling systems, rotary systems, swivels, well control systems, well monitoring systems, and offshore drilling equipment. It includes examples of calculating pump factors and pump rates. Schematics and diagrams are provided to illustrate blowout preventers, casing strings, capacities, and other drilling equipment. The document is intended to teach students about the equipment used in well drilling as part of a PETE 411 course.
DESIGN AND ANALYSIS OF CONVERGENT DIVERGENT NOZZLE USING CFDNetha Jashuva
CFD is a branch of fluid mechanics that uses
numerical methods and algorithms to solve and analyze
problems that involve fluid flows. Computers are used to
perform the calculations required to simulate the interaction
of liquids and gases with surfaces defined by boundary
conditions. In this thesis, CFD analysis of flow within
Convergent-Divergent supersonic nozzle of different cross
sections rectangular, square and circular has been performed.
The analysis has been performed according to the shape of the
supersonic nozzle and keeping the same input conditions. Our
objective is to investigate the best suited nozzle which gives
high exit velocity among the different cross sections
considered. The application of these nozzles is mainly in
torpedos. The work is carried out in two stages: 1.Modeling
and analysis of flow for supersonic nozzles of different cross
sections.2.Prediction of best suited nozzle among the nozzles
considered. In this, initially modeling of the nozzles has been
done in CATIA and later on mesh generation and analysis
have been carried out in ANSYS FLUENT 14.5 and various
contours like velocity, pressure, temperature have been taken
and their variation according to different nozzles has been
studied.
This document provides an overview of rocket nozzle design and operation. It discusses the basics of converging and converging-diverging nozzle flow. The primary nozzle types - cone, bell, and annular - are described. Details are given on over-expanded, ideally expanded, and under-expanded exhaust plume conditions depending on the ambient pressure. Examples like the Space Shuttle Main Engine nozzle are used to illustrate concepts. The document concludes with discussions on conical nozzle sizing and bell nozzle advantages over conical designs.
1. The document discusses wind tunnels, which are devices used to study aerodynamic forces on models in controlled airflow conditions.
2. It describes various types of wind tunnels classified by speed (low speed vs high speed) and operation mode. Low speed wind tunnels aim to reduce turbulence using screens, honeycombs, and contractions prior to the test section.
3. Key components like the diffuser are explained, which recovers kinetic energy as pressure. The document emphasizes the importance of dynamic similarity between models and full-scale objects through non-dimensional parameters like Reynolds and Mach numbers.
Overview of artificial lift technology and introduction to esp systemGiuseppe Moricca
This document outlines the agenda for a 5-day course on electric submersible pump systems. Day 1 provides an overview of artificial lift technology and introduction to ESP systems. Days 2-3 cover ESP basic design, operational factors, system components and their operational features. Day 4 addresses ESP system design through a step-by-step procedure. Day 5 focuses on ESP installation, monitoring, optimization, troubleshooting and diagnostics. The document also includes detailed schedules and learning objectives for each day of the course.
This document summarizes an experimental investigation into the effect of turbine phantom cooling on the suction side of a nozzle guide vane. Phantom cooling refers to coolant injected from the endwall that moves toward the airfoil suction side, providing a secondary cooling effect. The study uses pressure sensitive paint to measure film cooling effectiveness on a scale model turbine vane under different blowing ratios and incidence angles. It finds that incidence angle can alter the direction of coolant jets on the pressure side and change film cooling effectiveness distributions on the airfoil suction side.
The document summarizes modifications made to a two-stage centrifugal compressor to convert it into a single-stage compressor suitable for laboratory testing. Key modifications included replacing the refrigerant fluid with air, installing an external drive motor instead of the internal hermetic motor, and adding static pressure taps to the vaneless diffuser and volute casing. Experimental results showed the compressor was operating off-design, with the vaneless diffuser and volute being too large for the mass flow rates tested. Pressure maps revealed distortion in the diffuser and volute due to the tongue region, reducing stage performance.
This document discusses nozzles and provides objectives and information about different types of nozzles. It defines nozzles and diffusers, describes convergent and convergent-divergent nozzle shapes. It also defines critical pressure ratio and maximum mass flow, and provides equations to calculate properties like area, temperature, and velocity at different points in a nozzle. An example calculation is provided to demonstrate determining the throat and exit areas of a convergent-divergent nozzle.
This document provides an overview of drilling equipment used on oil rigs. It discusses various components of the rig including rig pumps, solids control equipment, air drilling systems, rotary systems, swivels, well control systems, well monitoring systems, and offshore drilling equipment. It includes examples of calculating pump factors and pump rates. Schematics and diagrams are provided to illustrate blowout preventers, casing strings, capacities, and other drilling equipment. The document is intended to teach students about the equipment used in well drilling as part of a PETE 411 course.
DESIGN AND ANALYSIS OF CONVERGENT DIVERGENT NOZZLE USING CFDNetha Jashuva
CFD is a branch of fluid mechanics that uses
numerical methods and algorithms to solve and analyze
problems that involve fluid flows. Computers are used to
perform the calculations required to simulate the interaction
of liquids and gases with surfaces defined by boundary
conditions. In this thesis, CFD analysis of flow within
Convergent-Divergent supersonic nozzle of different cross
sections rectangular, square and circular has been performed.
The analysis has been performed according to the shape of the
supersonic nozzle and keeping the same input conditions. Our
objective is to investigate the best suited nozzle which gives
high exit velocity among the different cross sections
considered. The application of these nozzles is mainly in
torpedos. The work is carried out in two stages: 1.Modeling
and analysis of flow for supersonic nozzles of different cross
sections.2.Prediction of best suited nozzle among the nozzles
considered. In this, initially modeling of the nozzles has been
done in CATIA and later on mesh generation and analysis
have been carried out in ANSYS FLUENT 14.5 and various
contours like velocity, pressure, temperature have been taken
and their variation according to different nozzles has been
studied.
This document provides an overview of rocket nozzle design and operation. It discusses the basics of converging and converging-diverging nozzle flow. The primary nozzle types - cone, bell, and annular - are described. Details are given on over-expanded, ideally expanded, and under-expanded exhaust plume conditions depending on the ambient pressure. Examples like the Space Shuttle Main Engine nozzle are used to illustrate concepts. The document concludes with discussions on conical nozzle sizing and bell nozzle advantages over conical designs.
1. The document discusses wind tunnels, which are devices used to study aerodynamic forces on models in controlled airflow conditions.
2. It describes various types of wind tunnels classified by speed (low speed vs high speed) and operation mode. Low speed wind tunnels aim to reduce turbulence using screens, honeycombs, and contractions prior to the test section.
3. Key components like the diffuser are explained, which recovers kinetic energy as pressure. The document emphasizes the importance of dynamic similarity between models and full-scale objects through non-dimensional parameters like Reynolds and Mach numbers.
Overview of artificial lift technology and introduction to esp systemGiuseppe Moricca
This document outlines the agenda for a 5-day course on electric submersible pump systems. Day 1 provides an overview of artificial lift technology and introduction to ESP systems. Days 2-3 cover ESP basic design, operational factors, system components and their operational features. Day 4 addresses ESP system design through a step-by-step procedure. Day 5 focuses on ESP installation, monitoring, optimization, troubleshooting and diagnostics. The document also includes detailed schedules and learning objectives for each day of the course.
This document summarizes an experimental investigation into the effect of turbine phantom cooling on the suction side of a nozzle guide vane. Phantom cooling refers to coolant injected from the endwall that moves toward the airfoil suction side, providing a secondary cooling effect. The study uses pressure sensitive paint to measure film cooling effectiveness on a scale model turbine vane under different blowing ratios and incidence angles. It finds that incidence angle can alter the direction of coolant jets on the pressure side and change film cooling effectiveness distributions on the airfoil suction side.
A wind tunnel is a facility that provides a controlled airflow for testing aerodynamic models. It has a test section where models are placed and sensors measure forces like lift and drag. Wind tunnels are classified based on speed of airflow, air pressure, and size. They can have open or closed designs and use various flow visualization techniques to study airflow patterns.
Using the convergent steam nozzle type in the entranceSaif al-din ali
This document discusses using a convergent steam nozzle in the entrance region of a steam turbine. It provides background on steam turbines and how they work, describing how steam is expanded through nozzles to convert heat energy to kinetic energy. It then discusses different types of steam nozzles, focusing on convergent nozzles, and how nozzle shape affects steam velocity and pressure distribution. A numerical simulation will be performed to analyze pressure and velocity within a simple convergent nozzle design.
The document summarizes an experimental study that investigated the wind load on hexagonal cylinders. Static pressure distributions were measured on single and paired hexagonal cylinders in a wind tunnel at various wind speeds and angles of attack. Lower drag and lift forces were observed for hexagonal cylinders compared to square cylinders, approaching the lower values seen for circular cylinders. It was concluded that hexagonal cylinders experience significantly lower wind loads than square cylinders of the same width.
The document discusses nozzle thermodynamics. Some key points:
1. A nozzle is a duct with varying cross-sectional area used to accelerate fluid flow through a pressure drop. Common applications include jet engines, rockets, and flow measurement.
2. Nozzle shape is determined using the steady flow energy equation. For an ideal, frictionless case the process is isentropic. Area varies to maintain constant mass flow rate.
3. The throat is the minimum cross-sectional area point. Flow is sonic at the throat for designed operating conditions. Critical pressure ratio is when sonic velocity is first reached.
4. Nozzle performance is affected by operating above or below design back pressure. Maximum
The document provides details about the Refinery Modernisation Project (RMP) at Bharat Petroleum Corporation Ltd. Refinery in Mahul, Mumbai. Key points:
- RMP helped integrate new facilities with existing operations, increasing operational flexibility.
- RMP included utilities like power generation, steam production, cooling water systems, and a centralized flushing oil system.
- Process details are described for various units like crude preheat trains, desalter, pre-flash drum, furnace, and measurement of pressure and temperature.
- Pressure is measured using instruments like bourdon tubes, manometers, McLeod gauges, diaphragms, bellows, and differential pressure transmitters
The document discusses axial flow compressors. It begins with an overview that axial flow compressors have multiple stages, each with a row of rotor blades followed by a row of stator blades. The fluid is accelerated by the rotor blades and decelerated in the stator, converting kinetic to static pressure energy. Due to small pressure increases per stage, axial compressors require many stages. The document then provides details on the elementary theory, velocity triangles, degree of reaction, and three dimensional flow effects in axial compressors. It concludes with discussing the design process which includes choosing operating parameters, determining number of stages, calculating air angles, and testing.
Air Compressor in mechanical EngineeringNayan Dagliya
The document discusses different types of compressors and their applications. It begins by explaining that a compressor takes in atmospheric air, compresses it, and delivers high-pressure air to a storage vessel. It then describes two basic compressor types - positive displacement compressors that mechanically reduce air volume to increase pressure, and dynamic compressors that impart velocity energy to continuously flowing air. Specific compressor types are then outlined, including reciprocating compressors that use pistons, rotary vane compressors with rotating blades, and screw compressors that employ two rotating helical screws to compress air. Applications of compressed air in tools, spraying, mining, and pneumatic systems are also summarized.
This document provides information about steam nozzles and steam turbines. It discusses:
1. Steam nozzles convert the heat energy of steam into kinetic energy by accelerating steam through a passage of varying cross-section.
2. Steam turbines convert the high-pressure, high-temperature steam from a steam generator into rotational shaft work.
3. There are three main types of nozzles used in steam turbines: convergent, divergent, and convergent-divergent. Convergent-divergent nozzles are widely used today.
4. The document then discusses concepts like Mach number and critical pressure that are important for steam nozzle and turbine operation.
This document discusses aircraft intake aerodynamics, focusing on subsonic and transonic intake flows. For subsonic intakes, it examines types of intakes, approximate theories of frictional losses, pressure recovery characteristics, plenum chambers, and propeller turbine engines. It finds total pressure loss is from approach and duct losses, corrected for compressibility. For transonic flows, total losses include approach, duct losses corrected for compressibility, and shock losses. The goal of intake design is to provide air to the engine without suffocation while minimizing total pressure losses.
Design of sprinkler laterals, design of main line, selection of pumps,Suyog Khose
The document discusses the design of sprinkler irrigation systems, including the design of sprinkler laterals and main lines and selection of pumps. It covers topics such as selecting pipe sizes to minimize pressure variations in laterals, computing friction losses, determining pumping requirements based on sprinkler discharge and number of sprinklers, and factors to consider when selecting pumps to power sprinkler irrigation systems. The goal is to deliver water at a consistent pressure through laterals and sprinklers to irrigate fields in an efficient manner.
The document discusses the design methodology for a subsonic wind tunnel. It involves defining the test section dimensions and desired flow velocity, designing the wind tunnel components like the nozzle, diffusers, settling chamber based on the test section, calculating pressure losses throughout the components, determining overall pressure loss and flow velocity, and selecting appropriate fans to match the design. Key components are the nozzle, diffusers, settling chamber with honeycombs and screens, and corners. Design factors for these include area ratios, lengths, hydraulic diameters, porosity and Reynolds number.
Wind tunnels are used to simulate air flow around vehicles and measure forces, pressure, and heat transfer. There are various types including closed and open return, as well as subsonic, transonic, supersonic, and hypersonic tunnels. Testing involves force measurements, pressure tests, and flow visualization to analyze aerodynamic properties. A variety of instruments are used including force balances, pressure sensors, strain gauges, and laser equipment. Car testing quantifies aerodynamic forces on models to optimize vehicle design parameters. Major wind tunnel facilities are located around the world, with costs ranging from millions to tens of millions of dollars.
Centrifugal Compressor System Design & SimulationVijay Sarathy
The power point slides focuses on centrifugal compressor design, dynamic simulation including anti surge valve and hot gas bypass requirements. The topics covered are,
Centrifugal Compressor (CC) System Characteristics
Centrifugal Compressor (CC) Drivers
Typical Single Stage System
Start-up Scenario
Shutdown Scenario
Emergency Shutdown (ESD) Scenario
Centrifugal Compressor (CC) System Design Philosophy
Anti-Surge System
Recycle Arrangements
CC Driver Arrangements
General Notes
Surge occurs when the pressure behind a centrifugal compressor becomes higher than the outlet pressure, causing fluid to reverse flow into the compressor. This unstable phenomenon repeats in cycles around 1-2 Hz. To prevent surge, anti-surge control systems detect when the operating point approaches the surge line and open a recycle valve to increase inlet flow and move the operating point away from the surge line. Proportional-integral and proportional-integral-derivative algorithms are commonly used to control the recycle valve based on differences between the process variable and set point.
The document summarizes the results of a detailed flow investigation within a centrifugal pump equipped with a vaned diffuser. Unsteady velocity measurements were obtained in the impeller and diffuser at different radial planes. The analysis shows the presence of a complex, unsteady and periodic jet-wake flow structure in the impeller. At the impeller discharge, the mixing of the unsteady flow entering the diffuser is affected by the diffuser vanes, though periodic flow characteristics are still observed at the diffuser throat, indicating unsteady inlet conditions for the diffuser.
This document discusses the design and testing of a wind tunnel model to study shock wave boundary layer interactions. Key points:
- A model was designed for testing in CIRA's Scirocco Plasma Wind Tunnel to reproduce conditions from ESA's EXPERT reentry capsule during flight, focusing on interactions over the capsule's flap.
- Numerical simulations were used to help determine the model design and appropriate wind tunnel test conditions.
- The model was tested and measurements compared to numerical predictions, showing reasonable agreement.
- The results will help validate simulations of interactions on the full-scale EXPERT during its planned 2011 flight, completing the methodology of extrapolating ground test results to flight conditions.
The document provides information about conducting wind tunnel experiments for students in grades 8-12. It includes sample experiments such as measuring lift versus angle of attack and lift versus velocity. It also discusses governing equations, flow visualization techniques, how to make measurements, background on why wind tunnels are used, and selected references for further reading.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
Know Everything you want to know about steam nozzles(Turbine Excluded).Know more about De-Laval Nozzles and How we achieve Supersonic velocity from nozzles.Also get to know about other essentials such as Critical pressure ratio and Saturated Flow.You can use this ppt in your projects,journals.It is not copyright protected.
This document describes an experimental and computational study of flow over a blunt cylinder-flare model in high supersonic flow. Wind tunnel experiments were conducted in the TST-27 and ST-15 wind tunnels at Mach numbers from 3 to 4 and angles of attack up to 20 degrees. Measurements included surface pressure distributions, flow visualization using shadowgraph and Schlieren techniques, and digital holographic interferometry to obtain density distributions in the flowfield. Computational simulations of the inviscid flow were also performed using a three-dimensional Euler solver. The goal was to provide high-quality aerodynamic data to validate computational fluid dynamics codes for simulating high-speed flows with phenomena such as shocks, separation
The document describes a computational fluid dynamics (CFD) analysis of heat transfer in a rectangular channel with blockages containing elongated holes. A model of the channel was created in design software and meshed before performing CFD simulations. The simulations analyzed how heat transfer coefficients and Nusselt numbers varied with the pitch ratio of the blockages for different Reynolds numbers. Results showed that heat transfer initially increased with pitch ratio up to a value of 6.0, then decreased with further increases, due to changes in flow reattachment. Blockages with shorter holes enhanced heat transfer more but also increased pressure drops more compared to longer holes. The CFD results were also validated against available experimental data, with good agreement.
A wind tunnel is a facility that provides a controlled airflow for testing aerodynamic models. It has a test section where models are placed and sensors measure forces like lift and drag. Wind tunnels are classified based on speed of airflow, air pressure, and size. They can have open or closed designs and use various flow visualization techniques to study airflow patterns.
Using the convergent steam nozzle type in the entranceSaif al-din ali
This document discusses using a convergent steam nozzle in the entrance region of a steam turbine. It provides background on steam turbines and how they work, describing how steam is expanded through nozzles to convert heat energy to kinetic energy. It then discusses different types of steam nozzles, focusing on convergent nozzles, and how nozzle shape affects steam velocity and pressure distribution. A numerical simulation will be performed to analyze pressure and velocity within a simple convergent nozzle design.
The document summarizes an experimental study that investigated the wind load on hexagonal cylinders. Static pressure distributions were measured on single and paired hexagonal cylinders in a wind tunnel at various wind speeds and angles of attack. Lower drag and lift forces were observed for hexagonal cylinders compared to square cylinders, approaching the lower values seen for circular cylinders. It was concluded that hexagonal cylinders experience significantly lower wind loads than square cylinders of the same width.
The document discusses nozzle thermodynamics. Some key points:
1. A nozzle is a duct with varying cross-sectional area used to accelerate fluid flow through a pressure drop. Common applications include jet engines, rockets, and flow measurement.
2. Nozzle shape is determined using the steady flow energy equation. For an ideal, frictionless case the process is isentropic. Area varies to maintain constant mass flow rate.
3. The throat is the minimum cross-sectional area point. Flow is sonic at the throat for designed operating conditions. Critical pressure ratio is when sonic velocity is first reached.
4. Nozzle performance is affected by operating above or below design back pressure. Maximum
The document provides details about the Refinery Modernisation Project (RMP) at Bharat Petroleum Corporation Ltd. Refinery in Mahul, Mumbai. Key points:
- RMP helped integrate new facilities with existing operations, increasing operational flexibility.
- RMP included utilities like power generation, steam production, cooling water systems, and a centralized flushing oil system.
- Process details are described for various units like crude preheat trains, desalter, pre-flash drum, furnace, and measurement of pressure and temperature.
- Pressure is measured using instruments like bourdon tubes, manometers, McLeod gauges, diaphragms, bellows, and differential pressure transmitters
The document discusses axial flow compressors. It begins with an overview that axial flow compressors have multiple stages, each with a row of rotor blades followed by a row of stator blades. The fluid is accelerated by the rotor blades and decelerated in the stator, converting kinetic to static pressure energy. Due to small pressure increases per stage, axial compressors require many stages. The document then provides details on the elementary theory, velocity triangles, degree of reaction, and three dimensional flow effects in axial compressors. It concludes with discussing the design process which includes choosing operating parameters, determining number of stages, calculating air angles, and testing.
Air Compressor in mechanical EngineeringNayan Dagliya
The document discusses different types of compressors and their applications. It begins by explaining that a compressor takes in atmospheric air, compresses it, and delivers high-pressure air to a storage vessel. It then describes two basic compressor types - positive displacement compressors that mechanically reduce air volume to increase pressure, and dynamic compressors that impart velocity energy to continuously flowing air. Specific compressor types are then outlined, including reciprocating compressors that use pistons, rotary vane compressors with rotating blades, and screw compressors that employ two rotating helical screws to compress air. Applications of compressed air in tools, spraying, mining, and pneumatic systems are also summarized.
This document provides information about steam nozzles and steam turbines. It discusses:
1. Steam nozzles convert the heat energy of steam into kinetic energy by accelerating steam through a passage of varying cross-section.
2. Steam turbines convert the high-pressure, high-temperature steam from a steam generator into rotational shaft work.
3. There are three main types of nozzles used in steam turbines: convergent, divergent, and convergent-divergent. Convergent-divergent nozzles are widely used today.
4. The document then discusses concepts like Mach number and critical pressure that are important for steam nozzle and turbine operation.
This document discusses aircraft intake aerodynamics, focusing on subsonic and transonic intake flows. For subsonic intakes, it examines types of intakes, approximate theories of frictional losses, pressure recovery characteristics, plenum chambers, and propeller turbine engines. It finds total pressure loss is from approach and duct losses, corrected for compressibility. For transonic flows, total losses include approach, duct losses corrected for compressibility, and shock losses. The goal of intake design is to provide air to the engine without suffocation while minimizing total pressure losses.
Design of sprinkler laterals, design of main line, selection of pumps,Suyog Khose
The document discusses the design of sprinkler irrigation systems, including the design of sprinkler laterals and main lines and selection of pumps. It covers topics such as selecting pipe sizes to minimize pressure variations in laterals, computing friction losses, determining pumping requirements based on sprinkler discharge and number of sprinklers, and factors to consider when selecting pumps to power sprinkler irrigation systems. The goal is to deliver water at a consistent pressure through laterals and sprinklers to irrigate fields in an efficient manner.
The document discusses the design methodology for a subsonic wind tunnel. It involves defining the test section dimensions and desired flow velocity, designing the wind tunnel components like the nozzle, diffusers, settling chamber based on the test section, calculating pressure losses throughout the components, determining overall pressure loss and flow velocity, and selecting appropriate fans to match the design. Key components are the nozzle, diffusers, settling chamber with honeycombs and screens, and corners. Design factors for these include area ratios, lengths, hydraulic diameters, porosity and Reynolds number.
Wind tunnels are used to simulate air flow around vehicles and measure forces, pressure, and heat transfer. There are various types including closed and open return, as well as subsonic, transonic, supersonic, and hypersonic tunnels. Testing involves force measurements, pressure tests, and flow visualization to analyze aerodynamic properties. A variety of instruments are used including force balances, pressure sensors, strain gauges, and laser equipment. Car testing quantifies aerodynamic forces on models to optimize vehicle design parameters. Major wind tunnel facilities are located around the world, with costs ranging from millions to tens of millions of dollars.
Centrifugal Compressor System Design & SimulationVijay Sarathy
The power point slides focuses on centrifugal compressor design, dynamic simulation including anti surge valve and hot gas bypass requirements. The topics covered are,
Centrifugal Compressor (CC) System Characteristics
Centrifugal Compressor (CC) Drivers
Typical Single Stage System
Start-up Scenario
Shutdown Scenario
Emergency Shutdown (ESD) Scenario
Centrifugal Compressor (CC) System Design Philosophy
Anti-Surge System
Recycle Arrangements
CC Driver Arrangements
General Notes
Surge occurs when the pressure behind a centrifugal compressor becomes higher than the outlet pressure, causing fluid to reverse flow into the compressor. This unstable phenomenon repeats in cycles around 1-2 Hz. To prevent surge, anti-surge control systems detect when the operating point approaches the surge line and open a recycle valve to increase inlet flow and move the operating point away from the surge line. Proportional-integral and proportional-integral-derivative algorithms are commonly used to control the recycle valve based on differences between the process variable and set point.
The document summarizes the results of a detailed flow investigation within a centrifugal pump equipped with a vaned diffuser. Unsteady velocity measurements were obtained in the impeller and diffuser at different radial planes. The analysis shows the presence of a complex, unsteady and periodic jet-wake flow structure in the impeller. At the impeller discharge, the mixing of the unsteady flow entering the diffuser is affected by the diffuser vanes, though periodic flow characteristics are still observed at the diffuser throat, indicating unsteady inlet conditions for the diffuser.
This document discusses the design and testing of a wind tunnel model to study shock wave boundary layer interactions. Key points:
- A model was designed for testing in CIRA's Scirocco Plasma Wind Tunnel to reproduce conditions from ESA's EXPERT reentry capsule during flight, focusing on interactions over the capsule's flap.
- Numerical simulations were used to help determine the model design and appropriate wind tunnel test conditions.
- The model was tested and measurements compared to numerical predictions, showing reasonable agreement.
- The results will help validate simulations of interactions on the full-scale EXPERT during its planned 2011 flight, completing the methodology of extrapolating ground test results to flight conditions.
The document provides information about conducting wind tunnel experiments for students in grades 8-12. It includes sample experiments such as measuring lift versus angle of attack and lift versus velocity. It also discusses governing equations, flow visualization techniques, how to make measurements, background on why wind tunnels are used, and selected references for further reading.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
Know Everything you want to know about steam nozzles(Turbine Excluded).Know more about De-Laval Nozzles and How we achieve Supersonic velocity from nozzles.Also get to know about other essentials such as Critical pressure ratio and Saturated Flow.You can use this ppt in your projects,journals.It is not copyright protected.
This document describes an experimental and computational study of flow over a blunt cylinder-flare model in high supersonic flow. Wind tunnel experiments were conducted in the TST-27 and ST-15 wind tunnels at Mach numbers from 3 to 4 and angles of attack up to 20 degrees. Measurements included surface pressure distributions, flow visualization using shadowgraph and Schlieren techniques, and digital holographic interferometry to obtain density distributions in the flowfield. Computational simulations of the inviscid flow were also performed using a three-dimensional Euler solver. The goal was to provide high-quality aerodynamic data to validate computational fluid dynamics codes for simulating high-speed flows with phenomena such as shocks, separation
The document describes a computational fluid dynamics (CFD) analysis of heat transfer in a rectangular channel with blockages containing elongated holes. A model of the channel was created in design software and meshed before performing CFD simulations. The simulations analyzed how heat transfer coefficients and Nusselt numbers varied with the pitch ratio of the blockages for different Reynolds numbers. Results showed that heat transfer initially increased with pitch ratio up to a value of 6.0, then decreased with further increases, due to changes in flow reattachment. Blockages with shorter holes enhanced heat transfer more but also increased pressure drops more compared to longer holes. The CFD results were also validated against available experimental data, with good agreement.
Cfd analysis of turbulence in a gas turbine combustor with reference to the c...IAEME Publication
This document discusses computational fluid dynamics (CFD) analysis of turbulence in a gas turbine combustor with reference to exit phenomena. It summarizes several studies that have used experimental and computational methods to model combustor exit profiles and their effects on secondary flows in turbine vanes. The document outlines CFD models of different combustor configurations, including variations in cooling schemes, dilution jets, and exit slots. Results show that dilution jets and exit slots can create non-uniformities in temperature, pressure and velocity at the combustor exit which influence the development of secondary flows in downstream vanes. Understanding these interactions is important for improving turbine performance and cooling effectiveness.
Cfd analysis of turbulence in a gas turbine combustor with reference to the c...IAEME Publication
This document discusses computational fluid dynamics (CFD) analysis of turbulence in a gas turbine combustor with reference to exit phenomena. It analyzes the interaction between the combustor and turbine regarding increased temperatures and heat transfer. The objective is to better understand non-uniformities in the flow field at the combustor exit in terms of temperature, pressure and velocity in the spanwise and pitchwise directions. The analysis uses CFD to model different combustor configurations and evaluate the effects on the exit flow field and downstream turbine vane.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document summarizes an experiment studying the effect of perforated ribs as vortex generators on air flow through a square channel. The experiment measured friction factor ratio and pressure drop for different configurations of perforated ribs, varying the ribs' aspect ratio and pitch-to-height ratio. Tests were run for aspect ratios of 2, 3, and 5 and pitch-to-height ratios of 4, 8, 12, and 16 over a Reynolds number range of 8,000 to 24,000. The results showed that friction factor ratio increased with Reynolds number, as higher flow velocities generated more vortices and turbulence, increasing pressure drop.
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Similar to Martinez,Reimann,Hoffie_AerothermoStudyFlapHEG (20)
1. AEROTHERMODYNAMIC STUDY
OF A GENERIC FLAP CONFIGURATION WITH GAP IN HEG
Jan Marinez Schramm(1)
, Bodo Reimann(2)
, Andreas Hoffie(2)
, José M. A. Longo(2)
, Klaus Hannemann(1)
(1)
German Aerospace Center, Bunsenstraße 10, 37073 Göttingen, Germany, jan martinez@dlr.de
(2)
German Aerospace Center, DLR, Lilienthalplatz 7, 38108 Braunschweig, bodo reimann@dlr.de
ABSTRACT
In preparation of the flight of the European
eXPErimental Re-entry Testbed (EXPERT) the
German Aerospace Center (DLR) carried out a number
of experimental and numerical investigations for a
generic flap configuration to improve the understanding
regarding flap efficiency and heating.
1. INTRODUCTION
Within the framework of EXPERT the DLR participates
on the open flap payload 5 to improve the understanding
regarding flap efficiency and heating. The major interest
was to investigate strong viscous interaction effects,
transitional flow behaviour and the effect of high
temperature reacting flow. In preparation of the flight
experimental and numerical investigations of these
effects have been carried out.
For this study a simplified geometry with a cylindrical
nose followed by a ramp with embedded open flap has
been used. In contradiction to the real EXPERT capsule
the generic model offers the possibility to open the flap
gap to measure gap heating. Fig. 1 shows a comparison
of the geometry of the EXPERT capsule and the
investigated generic model.
Figure 1: EXPERT capsule and generic model.
2. HIGH ENTHALPY SHOCK TUNNEL
GÖTTINGEN
The experimental part of the study has been carried out
in the High Enthalpy Shock Tunnel Göttingen (HEG) of
the DLR. The HEG is a free piston driven shock tunnel
([1], [2], [3]) and was developed and constructed in the
framework of the European HERMES program over the
period 1989 – 1991. It was commissioned for use in
1991, at that time being the largest facility of its type
worldwide. Since then it was extensively used in a large
number of national and international space and
hypersonic flight projects. The research activities which
were always strongly linked with computational fluid
dynamics (CFD) investigations range from the
calibration process of the facility and the study of basic
aerodynamic configurations, which are well suited to
investigate fundamental aspects of high enthalpy flows
to the investigation of complex re-entry, hypersonic
flight and integrated scramjet configurations. A
schematic of HEG is given in Fig. 2.
Figure 2: Schematic drawing of the High Enthalpy
Shock Tunnel Göttingen (HEG).
In a free piston driven shock tunnel, the conventional
driver of a shock tunnel is replaced by a free piston
driver. This concept was proposed by Stalker [4]. A
schematic and wave diagram of this type of facility is
shown in Fig. 3. Free piston driven shock tunnels
consist of a secondary reservoir, a compression tube,
separated from an adjoining shock tube via the primary
2. diaphragm, and a subsequent nozzle, test section and
dump tank.
Figure 3: Schematic and wave (x-t) diagram of a free
piston driven shock tunnel like the HEG.
The high pressure air stored in the secondary reservoir
is utilized to accelerate a heavy piston down the
compression tube. The driver gas temperature increases
with the driver gas volumetric compression ratio. When
the main diaphragm burst pressure is reached it ruptures
and the wave process as in a conventional reflected
shock tunnel is initiated (see Fig. 3). A shock wave is
moving into the driven section and the head of a centred
expansion wave is moving into the high pressure region.
The numbers used in Fig. 3 denote distinct regions of
the flow. Region 1 contains the test gas at the initial
shock tube filling conditions and region 4 contains the
hot, compressed driver gas after piston compression.
Region 2 contains the shock compressed test gas, while
in region 3, the driver gas processed by the unsteady
expansion wave is contained. The test and driver gas are
separated by a contact surface. After reflection of the
incident shock wave at the right end wall of the shock
tube, the test gas is brought to rest in region 0.
Subsequently, the reflected shock wave penetrates the
contact surface. Reflected shock tunnels are
characterised by a convergent - divergent nozzle which
is attached to the end of the shock tube. A thin
secondary diaphragm is placed at the nozzle entrance in
order to allow evacuation of the nozzle, test section and
vacuum tank before the run. The nozzle entrance
diameter is chosen sufficiently small such that the
incident shock wave is almost completely reflected. The
stagnant slug of test gas, generated by the shock
reflection in region 0, is subsequently expanded through
the hypersonic nozzle. The nozzle flow starting process
is characterised by a wave system which passes through
the nozzle before a steady flow is established (see
Fig.3). The incident shock wave (a) is followed by a
contact surface (b), an upstream facing secondary shock
wave (c) and the upstream head of an unsteady
expansion (d). The trajectory of the piston is chosen in a
way that after main diaphragm rupture, the pressure and
temperature of the driver gas in region 4 is maintained
approximately constant. This is achieved by selecting
the velocity of the piston at diaphragm rupture, and
therefore the subsequent movement of the piston such
that it compensates for the loss of the driver gas flowing
into the shock tube. For that reason, in contrast to the
constant volume driver of conventional shock tunnels,
the free piston driver is a constant pressure driver. Due
to the large forces occurring during the operation of the
free piston driver, the compression tube, shock tube,
nozzle assembly is allowed to move freely in axial
direction. The test section and the vacuum tank remain
stationary. A sliding seal is used at the nozzle / test
section interface.
Figure 4: Binary scaling of EXPERT trajectory and
HEG conditions with corresponding angle of attack.
Fig. 4 shows the planned re-entry trajectory of EXPERT
and the available HEG conditions in terms of the binary
scaling parameter ρL versus flight velocity u.
Additionally the corresponding angle of attack (AoA)
for the selected trajectory is given.
3. TEST MATRIX
For the wind tunnel campaign, HEG conditions III and
IV have been selected to perform the measurements at
various AoA and flap deflection angles (FdA) with open
and closed slit. In Tab. 1 the experimental configuration
is given together with the boundary layer assumption
(BLA) for the CFD rebuilding for the cases presented in
this paper.
condition AoA FdA gap bla
HEG III 0° 20° open laminar
HEG III 0° 30° open laminar
HEG III 0° 20° closed laminar
HEG III 0° 20° closed transitional
NUM PG 0° 20° closed laminar
Table 1: Test Matrix.
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
10
-1
10
-2
10
-3
10
-4
10
-5
10
-6
10
-7
0.0
0.5
1.0
1.5
2.0
2.5
3.0
EXPERT, Lref
= 1.55 m
HEG, Lref
= 0.4m
XXII
XIII
XIV
XXXI
III
IV II
I
ρL[kg/m
2
]
u [km/s]
AoA[°]
3. The free stream conditions for the numerical rebuilding
of the HEG experiments are listed in Tab. 2. A flow
condition with a perfect gas (NUM PG) assumption has
been investigated numerically additionally to study the
influence of high temperature effects.
condition III NUM PG
ρ∞ [g/m3
] 3.2 11.9
T∞ [K] 682.0 43.4
u∞ [m/s] 4672 1151
p∞ [Pa] 681.9 148.1
h∞ [MJ/kg] 13.0 0.7
Ma∞ 8.88 8.72
Re∞ [1/m] 4.53 ּ 105
5.07 ּ 106
c(N2) 0.73553 -
c(N) 0.00001 -
c(O2) 0.13500 -
c(O) 0.07850 -
c(NO) 0.05096 -
Table 2: Free stream conditions for the numerical
rebuilding.
4. EXPERIMENTAL SETUP
The idea for the present double ramp model was to
simplify the shape of the EXPERT vehicle, while a
similar flow topology should be created. The cylindrical
nose creates a strong bow shock and induces strong
relaxation processes of the gas within the shock layer.
The same behaviour is expected for the flow around the
nose region of the EXPERT configuration. A three
dimensional view of the model is given in Fig. 5
together with the coordinate system used in the results
section
Figure 5: Three dimensional view of the double ramp
model.
The flap region of the configuration has been designed
in such a way, that the maximum control surface area
possible in HEG has been realized. The flap is 220mm
long and 240mm wide. The EXPERT flap has a length
of 300mm and is 377mm wide. In contrast to the
EXPERT capsule where the flap hinge line is closed, the
model is designed in such a way, that the flap hinge line
is open, such that the flow can pass underneath the flap.
For further testing however, the slit between the body
and the flap can be closed in order to examine the
influence of the slit. The upper surfaces of body (ramp)
and flap have been instrumented with pressure
transducers and thermocouples.
Figure 6: Side view including main dimensions of the
double ramp model(top) and double ramp model
mounted in the HEG test section (bottom).
The nose part of the model is removable and
instrumented with pressure transducers and
thermocouples in axial and radial direction. The flap
and the model body instrumentation are realized by
variable sensor inserts that enable to change the
locations in the flow direction The variable inserts are
part of the surface and can be adjusted, which allows
placing the transducers at the position at flow features
that intend to be resolved. The minimum spacing is
6mm. Pressure and temperature sensors can be moved
independently and 35 inserts (sensors) are installed into
the model, where 20 are on the model body surface and
25 are one the flap surface. The gap between the model
body and the flap is also instrumented. Six
thermocouples are placed in the symmetry plane; three
pressure transducers and three thermocouples are placed
in the span wise direction. Fig. 6 shows the main
dimensions of the model and a photograph of the model
mounted in the test section of the HEG.
4. 5. DLR TAU CODE
The flow solver used in the present study is the DLR
TAU code. This code is a finite volume Euler/Navier-
Stokes solver, which can handle structured,
unstructured, and hybrid meshes and has already been
applied to a variety of configurations. The Reynolds
averaged Navier-Stokes (RANS) equations are
discretized by a finite volume technique using
tetrahedrons and prisms. Prismatic elements are used for
the boundary layer region, while the tetrahedral ones are
used in inviscid flow regions. The AUSMDV second
order upwind scheme with MUSCL reconstruction is
used for the inviscid fluxes. For time discretization,
including local time stepping, a three stage Runge-
Kutta, as well as an implicit, approximately factored
LU-SGS scheme is implemented. For acceleration,
multi-grid and explicit residual smoothing are available.
Furthermore, parallel computing is possible via domain
splitting and Message Passing Interface (MPI)
communication.
The transition from laminar to turbulent flow is
modelled by prescribing the transition location. For the
present model computations with transitional flow, the
transition line has been set at the windward flap hinge
line. This means that only the windward side of the
flaps was modelled as turbulent; all other parts have
been assumed laminar. In the presented cases, the two-
equation k-ω model described by Wilcox [5] was used.
This model has proven in earlier studies to be the only
one reliable for the investigated Mach number range. To
model the thermo-chemical behaviour of the flow,
Gupta's [6] five species chemical non-equilibrium
model was applied.
6. GRID
All of the numerical grids presented here have been
generated by the CENTAUR software.
Figure 7: Initial (left) and adapted grid (right) for the
open gap case and 20° flap deflection angle.
Major criteria for designing the meshes was to obtain a
high resolved surface grid and a high resolution of the
boundary layer by the prism mesh that will enable to
compute the heat flux at the highest possible degree of
accuracy. Although the flow across the present
configuration remains for the most part laminar, a goal
was to keep the y+ value below the value of 0.5. This
implied a short wall distance of the first prismatic layer.
Grid adaptation by cell division offers the possibility to
insert additional points only in region where clustering
is necessary. While the tetrahedra can be divided along
all edges, the prismatic elements are presently refined
only on their triangular faces. Based on the flow
solution points can be added, redistributed or removed.
Fig. 7 shows the symmetry plane of the initial grid and
the grid after several adaptation steps. Fig. 8 shows the
mesh near the hinge line with open and closed gap.
Figure 8: Enlarged view of the grid with open (left) and
closed gap (right).
7. RESULTS
Fig. 9 shows the computed flow topology with
normalized surface pressure distribution and skin-
friction lines for the ramp configuration with a flap
deflection of 20°. On the left hand side of the picture the
gap is open while on the right hand side it is closed.
Figure 9: Normalized pressure distribution and skin-
friction lines for the configuration with open (left) and
closed gap (right).
5. The skin friction lines show no flow separation on the
fore body in front of the hinge line. In Fig. 10 the same
results are shown for the back side of the model. It is
obvious that for the open gap case, where the flow is
allowed to pass underneath the flap, the heating in the
cavity is not more severe than for the close gap case.
Figure 10: Rear view of the model with normalized heat
flux distribution and skin friction lines. The picture
shows the configuration with open gap on the left-hand
side and with closed gap on the right-hand side.
Figs. 11 and 12 show the topology in the symmetry
plane with density gradient and Mach number contours.
The configuration with closed gap shows at the hinge
line a separation bubble with a shock in front.
Figure 11: Density gradient and Mach number contours
around the hinge line with open gap.
The case with closed gap shows only a very small
region of separated flow inside the gap. This numerical
result is confirmed by the HEG experiment.
Figure 12: Density gradient and Mach number contours
around the hinge line with closed gap.
Fig. 13 shows the computed and measured surface
pressure distribution along the symmetry plane of the
model. While for the closed flap the separation bubble
covers a region from x/L= 1 to 1.25, no separation is
resolved by the instrumentation when the gap is closed.
x/L
p/pstag
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
CFD, closed gap
Experiment, closed gap
CFD, open gap
Experiment, open gap
HEG condition III
aoa = 0°
fdf = 20°
Figure 13: Pressure distribution for the configuration
with 20° flap deflection with open and closed gap.
For higher flap deflection angles experimental and
numerical data differ. Fig. 14 shows normalized
pressure distributions along the stagnation line with
open gap for 20° and 30° flap deflection. Compared to
the 20° case the measurement for 30° flap deflection
shows flow separation which is not reproduced by the
numerical computation. The reason for this is not fully
understood and requires further investigation.
x/L
p/pstag
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
CFD, fdf=30°
Experiment, fdf=30°
CFD, fdf=20°
Experiment, fdf=20°
HEG condition III
aoa = 0°
open gap
Figure 14: Normalized pressure distributions for the
configuration with open gap with 20° and 30° flap
deflection angle.
Fig. 15 shows the normalized distribution of the heat
flux along the symmetry plane. The experimental data
are compared with a laminar and a transitional
computation. For the transitional one the wind-ward
side of the flap is modelled turbulent. The comparison
shows that the flow along the flap matches neither the
laminar nor the fully turbulent heating level. The
characteristic shows a more laminar behaviour.
6. x/L
q/qstag
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
CFD, laminar
CFD, transitional
Experiment
HEG condition III
aoa=0°
fdf=20°
closed gap
Figure 15: Normalized laminar and transitional heat
flux distribution for a configuration with closed gap.
Fig. 16 shows the cross-wise distribution of the
normalized heat flux inside the gap. The convective gap
heating is relative low. Also the effect of the gap flow to
the convective heating of the cavity behind the flap is
negligible.
y/L
q/qstag
-0.55-0.50-0.45-0.40-0.35-0.30-0.25-0.20-0.15-0.10-0.050.000.05
0.000
0.025
0.050
0.075
0.100
0.125
0.150
0.175
0.200
CFD
Experiment
HEG condition III
fdf=20°
aoa=0°
open gap
Figure 16: Normalized heat flux distribution inside the
gap in span-wise direction.
The comparison of the computed pitching moment is
shown in Fig. 17. Here the results for the numerical
rebuilding of the flow around this generic configuration
in terms of total pitching moment is compared for the
HEG condition III and the numerical perfect gas case.
Due dissociation of molecular nitrogen and oxygen in
the high enthalpy condition, the position of the shock
waves and therefore the surface pressure distribution
changes. For the investigated configuration these high
temperature effects cause a drop in total pitching
moment.
Ma/(Re)
1/2
Cm,y
0.000 0.005 0.010 0.015 0.020 0.025
0.0025
0.0026
0.0027
0.0028
0.0029
0.0030
perfect gas
HEG condition III
High-temperature effect
Figure 17: Influence of real gas effects on the total
value of the pitching moment.
8. CONCLUSION
Experiments in HEG have been carried out for a generic
wind tunnel model, which has been developed to create
a similar flow which the EXPERT vehicle will
experience during re-entry. The generic model could be
designed as such that the maximal control surface area
of the steering flap could be realized for HEG, which is
approximately half the area of the flight configuration.
With the model it was possible to measure surface
pressure and surface heat flux with an open and closed
gap between the model and the flap.
The experimental results for HEG condition III for FdA
of 20° at AoA of 0° show that an open gap reduces the
size of the separation bubble in the hinge line
drastically, e.g. it is not measurable in the experiments
any more. This result has been confirmed by the
numerical rebuilding of these two cases.
The surface heat flux measured on the flap at FdA of
20° for the closed gap configuration (with separation)
show, when compared to the numerical results, that the
reattachment on the surface is not purely laminar but
rather in a state between laminar and fully turbulent.
Comparing the experimental results for FdA of 20° and
30° for an open gap, the separation establishes again for
30° FdA. This result has not been reproduced by the
numerical rebuilding, and further investigation is
required to identify the cause.
7. 9. RFERENCES
[1] Hannemann, K., Schnieder, M., Reimann, B.,
Martinez Schramm, J.: The influence and delay
of driver gas contamination in HEG, AIAA
2000-2593, 21st AIAA Aerodynamic
Measurement Technology and Ground Testing
Conference, Denver, CO, 19-22 June, 2000
[2] Hannemann, K., High Enthalpy Flows in the
HEG Shock Tunnel: Experiment and Numerical
Rebuilding, AIAA 2003-0978, 41st AIAA
Aerospace Sciences Meeting and Exhibit, 6-9
Jan, Reno, Nevada, 2003
[3] Hannemann, K., Martinez Schramm, J., Karl, S.:
Recent Extension to the High Enthalpy Shock
Tunnel Göttingen (HEG), Proceedings of the 2nd
International ARA Days “10 Years after ARD”,
October 21-23, Arcachon-France, 2008.
[4] Stalker R. J.: A study of the free piston shock
tunnel. AIAA Journal, 12(5):2160-2165, 1967.
[5] Gupta, R. N., Yos, J. M., Thompson, R. A., Lee,
K.-P.: A Review of Reaction Rates and
Thermodynamic and Transport Properties for n
11-Species Air Model for Chemical and Thermal
Nonequilibrium Calculations to 30000K, RP
1232, NASA,1990.
[6] Wilcox D. C.: Turbulence Modeling, DCW
Industries, 1998.