Use of Hydrogen in Fiat Lancia Petrol engine, Combustion Process and Determin...IOSR Journals
To our path towards green economy, Hydrogen is often regarded to have a potential growth in the
coming future. However, the high cost of operation of fuel cell has often been a setback. If we could make use of
hydrogen gas as a fuel directly, the scope of development broadens. Owing to these aspects, this work primarily
focuses on the simulation technique of an Internal Combustion Spark Ignition Engine powered by Hydrogen gas.
The simulations of various stages have been carried out using the discrete approach, thereby investigating the
pressures and temperatures at various instants in the cycle. For the relative performance discussion we have
simulated the different cycles as ideal cycle, air fuel cycle and actual cycle. The resultant cyclic graph indicates
various discrepancies between ideal, air fuel and actual cycle. This analysis serves as a tool for a better
understanding of the variables involved and helps in optimizing engine design and fixing of various parameters,
including the determination of valve timings. Besides this, backfire, is the commonly faced problem with the
hydrogen engines. To reduce this effect, a fuel injectoris used for adding the gaseous fuel to the combustion
chamber.
Episode 59 : Introduction of Process Integration
Pinch Diagram and Heat Integration
Reference: Notes from course on “Modelling, design and control for process integration”, CAPEC, August 2000 (R. Dunn)
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Use of Hydrogen in Fiat Lancia Petrol engine, Combustion Process and Determin...IOSR Journals
To our path towards green economy, Hydrogen is often regarded to have a potential growth in the
coming future. However, the high cost of operation of fuel cell has often been a setback. If we could make use of
hydrogen gas as a fuel directly, the scope of development broadens. Owing to these aspects, this work primarily
focuses on the simulation technique of an Internal Combustion Spark Ignition Engine powered by Hydrogen gas.
The simulations of various stages have been carried out using the discrete approach, thereby investigating the
pressures and temperatures at various instants in the cycle. For the relative performance discussion we have
simulated the different cycles as ideal cycle, air fuel cycle and actual cycle. The resultant cyclic graph indicates
various discrepancies between ideal, air fuel and actual cycle. This analysis serves as a tool for a better
understanding of the variables involved and helps in optimizing engine design and fixing of various parameters,
including the determination of valve timings. Besides this, backfire, is the commonly faced problem with the
hydrogen engines. To reduce this effect, a fuel injectoris used for adding the gaseous fuel to the combustion
chamber.
Episode 59 : Introduction of Process Integration
Pinch Diagram and Heat Integration
Reference: Notes from course on “Modelling, design and control for process integration”, CAPEC, August 2000 (R. Dunn)
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Engineering webinar material dealing with power cycles (Carnot, Brayton, Otto and Diesel), power cycle components/processes (compression, combustion and expansion) and compressible flow (nozzle, diffuser and thrust) when air is considered as the working fluid.
Engineering webinar material dealing with simple and basic Brayton Cycle and power cycle components/processes and their T - s diagrams, ideal and real operation and major performance trends when air is considered as the working fluid.
Episode 54 : CAPE Problem Formulations
Computer Aided Process Engineering
Lecture 2: CAPE Problem Formulations
* Four types of CAPE problems
Flowsheeting Specification (Design) Optimization (Design) Synthesis (& Design)
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Recuperative heat exchangers in the exhaust nozzle of an Aero engineMOHAMMED FAZIL
This new technology provides environment friendly and fuel efficient aircraft engine for a Green Era.This is the best ever technology in the field of aircraft propulsion.
Episode 39 : Hopper Design
Problem:
1 -experiments with shear box jenike on a particulate catalyst to give the family
yield locus as in 1. given that the bulk density is 1000 kg/m3 particulates and wall friction angle is 15
a-from design chart silo cone, do design a mass flow hopper for the material.
b-if the average size is 100 um, calculate the discharge flow rate passing through the discharge opening
2 - For the above materials using stainless steel is required to store 1000 tons of particulate in it. Coefficient of friction at the wall is given as 0.45 for each value and the formula that you use the appropriate justify the design.
a - draw the dimensions of the silo you and draw a vertical stress profile and the wall of the silo whole time say powerful particle
b- specify the maximum vertical stress and the wall of the silo you
c - if you use several different approaches in the design you provide appropriate recommendations to your employer for work before the end of the casting device fabrication started.
d - if problems such as the formation of the entrance are available after a certain time interval suggest measures - flow improvement measures to be taken to your employer
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Thermal Analysis of the Wheel for Urban Rail Vehicle Considering Emergency Br...IJRES Journal
A straight-plate wheel model for urban rail vehicle considering emergency braking condition is
presented in the study.The thermal loads of urban rail vehicle wheel were calculated. The superposition rule of
the temperature and the stress was obtained, and the maximum temperature and the maximum thermal stress of
the new wheel and the abrasion to the limit wheel were compared. The results show that the maximum
temperature and the maximum thermal stress of the wheel tread appeared in the process of braking; the
maximum thermal stress of the wheel plate appeared in the end of braking; under the process of braking, the
temperature and thermal stress of abrasion to the limit wheel was greater than the new wheel. The work is not
only suitable for the research of the thermal fatigue, but also has an important reference value to the
optimizationdesign of rail wheels.
1 ijebm jan-2018-1-combustion adjustment in a naturalAI Publications
Shortage of detailed and accurate experimental data on fuel-air mixing in furnaces is due to the difficulty and complexity of measurements in flames. Although it may be possible with infra-Red camera to obtain an indication of what happens in the furnace by graphical image resolution this is not expected to be sufficiently detailed because it contains only the temperature gradient. More detailed information, however, may be obtained from the simulated resolution using Computational Fluid Dynamics (CFD) technique where the total number of elements/points defines the detailed level that can be displayed or captured in graphical image. Simulation resolution studies two aspects of the momentum effects on flame which are the forward momentum normally associated with the average outlet velocity of the combustion products and the lateral momentum caused by swirl. Following the American Petroleum Institute guidelines (API 560) for combustion adjustment in furnaces, it may be possible to have less emission and a maximum efficiency, but the potential interaction between the several operation and design factors are not thereby considered as in a mathematical model of CFD.
Optimization of time step and cfd study of combustion in di diesel engineeSAT 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
Engineering webinar material dealing with power cycles (Carnot, Brayton, Otto and Diesel), power cycle components/processes (compression, combustion and expansion) and compressible flow (nozzle, diffuser and thrust) when air is considered as the working fluid.
Engineering webinar material dealing with simple and basic Brayton Cycle and power cycle components/processes and their T - s diagrams, ideal and real operation and major performance trends when air is considered as the working fluid.
Episode 54 : CAPE Problem Formulations
Computer Aided Process Engineering
Lecture 2: CAPE Problem Formulations
* Four types of CAPE problems
Flowsheeting Specification (Design) Optimization (Design) Synthesis (& Design)
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Recuperative heat exchangers in the exhaust nozzle of an Aero engineMOHAMMED FAZIL
This new technology provides environment friendly and fuel efficient aircraft engine for a Green Era.This is the best ever technology in the field of aircraft propulsion.
Episode 39 : Hopper Design
Problem:
1 -experiments with shear box jenike on a particulate catalyst to give the family
yield locus as in 1. given that the bulk density is 1000 kg/m3 particulates and wall friction angle is 15
a-from design chart silo cone, do design a mass flow hopper for the material.
b-if the average size is 100 um, calculate the discharge flow rate passing through the discharge opening
2 - For the above materials using stainless steel is required to store 1000 tons of particulate in it. Coefficient of friction at the wall is given as 0.45 for each value and the formula that you use the appropriate justify the design.
a - draw the dimensions of the silo you and draw a vertical stress profile and the wall of the silo whole time say powerful particle
b- specify the maximum vertical stress and the wall of the silo you
c - if you use several different approaches in the design you provide appropriate recommendations to your employer for work before the end of the casting device fabrication started.
d - if problems such as the formation of the entrance are available after a certain time interval suggest measures - flow improvement measures to be taken to your employer
SAJJAD KHUDHUR ABBAS
Ceo , Founder & Head of SHacademy
Chemical Engineering , Al-Muthanna University, Iraq
Oil & Gas Safety and Health Professional – OSHACADEMY
Trainer of Trainers (TOT) - Canadian Center of Human
Development
Thermal Analysis of the Wheel for Urban Rail Vehicle Considering Emergency Br...IJRES Journal
A straight-plate wheel model for urban rail vehicle considering emergency braking condition is
presented in the study.The thermal loads of urban rail vehicle wheel were calculated. The superposition rule of
the temperature and the stress was obtained, and the maximum temperature and the maximum thermal stress of
the new wheel and the abrasion to the limit wheel were compared. The results show that the maximum
temperature and the maximum thermal stress of the wheel tread appeared in the process of braking; the
maximum thermal stress of the wheel plate appeared in the end of braking; under the process of braking, the
temperature and thermal stress of abrasion to the limit wheel was greater than the new wheel. The work is not
only suitable for the research of the thermal fatigue, but also has an important reference value to the
optimizationdesign of rail wheels.
1 ijebm jan-2018-1-combustion adjustment in a naturalAI Publications
Shortage of detailed and accurate experimental data on fuel-air mixing in furnaces is due to the difficulty and complexity of measurements in flames. Although it may be possible with infra-Red camera to obtain an indication of what happens in the furnace by graphical image resolution this is not expected to be sufficiently detailed because it contains only the temperature gradient. More detailed information, however, may be obtained from the simulated resolution using Computational Fluid Dynamics (CFD) technique where the total number of elements/points defines the detailed level that can be displayed or captured in graphical image. Simulation resolution studies two aspects of the momentum effects on flame which are the forward momentum normally associated with the average outlet velocity of the combustion products and the lateral momentum caused by swirl. Following the American Petroleum Institute guidelines (API 560) for combustion adjustment in furnaces, it may be possible to have less emission and a maximum efficiency, but the potential interaction between the several operation and design factors are not thereby considered as in a mathematical model of CFD.
Optimization of time step and cfd study of combustion in di diesel engineeSAT 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 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.
A SIMULATE MODEL FOR ANALYZING THE EFFECT OF ENGINE DESIGN PARAMETERS ON THE ...Barhm Mohamad
A mathematical and simulation model has been developed to simulate a spark ignition engine
operation cycle. The programme written from this simulation model and modified so can be used to
assist in the design of a spark ignition engine for alternative fuels as well as to study many design
parameters such as the effect of engine design parameter like stroke and diameter of the cylinder on
the performance and exhaust emissions of spark ignition engines
Diesel Engine Combustion Simulation using Computational Fluid DynamicsIDES Editor
Diesel engines are used in automotive and stationary
applications. The main problem with diesel engines is emissions
of nitrogen oxides (NOx) and particulates. In order to minimize
the emissions, it is necessary to design the diesel engine with
better in-cylinder flow (air-fuel mixing) and combustion
process. Computational Fluid Dynamics (CFD) simulation
helps to understand the Diesel engine temperature distribution
and NOx species concentrations with respect to time. A small
direct injection (DI) engine was chosen for the study. CFD
simulation results were compared with that of engine emission
tests. Results were found to be in agreement with NOx
emissions. This paper also presents the simulation results of
direct injection diesel engine in-cylinder flow (air-fuel mixing)
and combustion.
CFD Studies of Combustion in Direct Injection Single Cylinder Diesel Engine U...IJERA Editor
In this study the simulation process of non-premixed combustion in a direct injection single cylinder diesel engine has been described. Direct injection diesel engines are used both in heavy duty vehicles and light duty vehicles. The fuel is injected directly into the combustion chamber. The fuel mixes with the high pressure air in the combustion chamber and combustion occurs. Due to the non-premixed nature of the combustion occurring in such engines, non-premixed combustion model of ANSYS FLUENT 14.5 can be used to simulate the combustion process. A 4-stroke diesel engine corresponds to one fuel injector hole without considering valves was modeled and combustion simulation process was studied. Here two types of combustion chambers were compared. Combustion studies of both chambers:- shallow depth and hemispherical combustion chambers were carried out. Emission characteristics of both combustion chambers had also been carried out. The obtained results are compared. It has been found that hemispherical combustion chamber is more efficient as it produces higher pressure and temperature compared to that of shallow depth combustion chamber. As the temperature increases the formation of NOx emissions and soot formation also get increased.
CFD Analysis on the Effect of Injection Timing for Diesel Combustion and Emis...IJERA Editor
This paper describes the effect of injection timing in diesel combustion. Ansys Fluent a computational fluid dynamics tool is used to study the combustion of diesel with three different injection timing. The fuel is injected before TDC, at TDC and after TDC. The parameters such as temperature, pressure, velocity, density, soot and NOx emission are compared. The specie transport model is used for modelling the combustion. Standard k-e (2 equ) is used for modelling the turbulence. The analysis is carried out by only considering the compression and expansion strokes. The pressure reaches the maximum when the fuel is injected before TDC and the maximum temperature is when injected at TDC. The NOx emission is less when the fuel is injected at TDC and the soot formation is when fuel injected before TDC.
simulation and analysis of 4 stroke single cylinder direct injection diesel e...Ijripublishers Ijri
A zero dimensional model has been used as a model to investigate the combustion performance of a single cylinder direct injection diesel engine fuelled by high speed diesel. The numerical simulation was performed at different speeds and compression ratios. The pressure, temperature diagrams vs crank angle are plotted. The simulation model includes sub models for various frictional pressure losses, fuel inflow rate with crank angle.
A solution procedure is developed for solving the available equations using numerical methods. An appropriate C++ code is written for brake power, friction power, indicated power, brake thermal efficiency are simulated. Experiment was conducted on available four stroke diesel engine and the model is validated.
KEYWORDS: Simulation model, combustion performance, zero dimensional model, numerical simulation, indicated power, brake power, brake thermal efficiency, friction power.
To reduce detrimental gases for environment NOX, CO from Exhaust gas Exhaust Gas Recirculation (EGR) is done in engine. Based on Hiroyasu model several Diesel Combustion Models have been developed to design diesel engines adapted to future exhaust gas regulations. They developed a driving mode simulator to estimate vehicle performance. For Premixed Charge Compression Ignition (PCI) Schreiber Model is introduced to adjust the reaction speed constant but not possible to calculate ethylene (C2H4) and CO. Again to expand the Hiroyasu model for calculating ethylene (C2H4) and CO in the exhaust emissions, Tsurushima reduced kinetic model was introduced together with characteristic mixing time scale. Direct introduction of the reaction model to the basic combustion model did not give good simulation result for experimental data. However by introducing mixing time scale to take into account local heterogeneity of the mixture, the simulation accuracy was significantly improved. In this study, I shall work on later model. Simulation will be done at different EGR rate for different Crank Angle (CA) separately. There is a possibility of simulating the rates of heat release and emissions including ethylene (C2H4) and CO for the both combustions of spray diffusion flame and of homogeneous charge compression ignition (HCCI).
Cfd Studies of Two Stroke Petrol Engine ScavengingIJERA Editor
This project deals with the numerical analysis of 2 stroke engine scavenging in two cases. One with an existing condition (Flat headed pistons) and another with a new design (Dome headed piston) .The numerical analysis is done with help of CFD software ANSYS FLUENT 14.5. Here, the modeling of engine piston with flat headed type and with dome headed types was done in workbench. In ANSYS FLUENT after the geometrical design, for the dynamic motion meshing is used and set up species transport model also. At first the scavenging effect of flat headed piston is analyzed. Later the simulation of piston with dome headed type was also checked. Analyzing the variations from each and selected the best method for scavenging. Finally the scavenging efficiency is calculated for both type arrangements.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
From Daily Decisions to Bottom Line: Connecting Product Work to Revenue by VP...
186 ashish
1. Simulation Models for Spark Ignition
Engine: A Comparative Performance Study
Ashish Chaudhari, Upendra Garg, Vinayak Kulkarni, Niranjan Sahoo
Indian Institute of Technology Guwahati
Guwahati, Assam, INDIA-781039
IV th International Conference on Advances in Energy Research, IIT BOMBAY 2013
2. PRESENTATION OUTLINE
Introduction
Background
Objectives
Model Development
Results and Discussion
Validation of Simulink Model
Validation of CFD Model
Conclusions
December 10, 2013
ICAER-2013
Slide 2 of 32
3. INTRODUCTION
INTRODUCTION
- The Internal combustion engines have been present since a century and their
performance, fuel economy has been greatly improved from the past and will
continue to increase.
- There has been a lot of research going on worldwide experimentally to bring new fuel
injection and combustion technologies for gasoline and diesel engines such as HCCI
(Homogeneous Charge Compression Ignition), GDI (Gasoline Direct injection) etc.
which are more efficient and produce lesser emissions [1].
- All the technologies introduced, cannot be tested experimentally as it is costly affair
and time consuming.
- The mathematical model based simulation using different environments like
Simulink, CFD etc makes the analysis easy, less time consuming and economical, for
the different technologies.
- The results of these simulations can be implemented for the new technology in the
engine.
December 10, 2013
ICAER-2013
Slide 3 of 32
4. BACKGROUND
BACKGROUND
Sr No
Name of author
Work reported
Fuel used
Outcome
01
Ismail and
Mehta(2011)
Estimation of irreversibility
using quasi –three dimensional
combustion model
Hydrogen fuel More than 90% fuel
undergoes combustion and
20-30% availability found
destroyed.
02
Rakopoulos et
al.(2005)
Computationally development of
combustion model for observing
the effect of irreversibility
Hydrogen and
hydrocarbon
fuel
Availability destroyed
found to be14.99 to
15.02%..
03
Hongqing and
Huijie (2010)
Second law analysis with two
zone combustion model
Surrogate
fuels
Found availability
destroyed around 18.9%.
04
Al-Baghdadi
(2006)
the effect of different fuels alone
or their mixtures on the
performance parameters and
toxic emissions using a 2-zone
simulation model.
Gasoline,
ethanol,
hydrogen
Ethanol add with 30%
gasoline improves output
power, reduces NOx. it
increases heat release rate
and also sfc.
05
Wu et al.,
(2009)
developed the modified heat
transfer model for predicting the
heat transfer rate value
Gasoline
accurate and improved
over the other models
developed by researchers.
December 10, 2013
ICAER-2013
Slide 4 of 32
5. OBJECTIVES
OBJECTIVES
- To develop a computer model for simulating a 4-stroke SI engine running on
any hydrocarbon fuel.
- Model should take into account realistic heat release during combustion and
heat loss from walls.
- Model should predict the cylinder pressure and temperature for one
thermodynamic cycle.
- It should predict performance related variables such as Indicated W.D. ,
IMEP, efficiency, power and torque for a given engine at any operating
condition.
December 10, 2013
ICAER-2013
Slide 5 of 32
6. MODEL DEVELOPMENT
MODEL DEVELOPMENT
- A Single-zone, zero dimensional thermodynamic model is chosen for computer
simulation for a four stroke SI engine.
- The model is divided into parts (subsystems) with different processes
(compression, combustion, expansion, exhaust and intake) during 720º crank
angle (CA) of one-thermodynamic cycle in the following sequence:
- intake valve closing (IVC),
- spark timing,
- end of combustion (EOC),
- exhaust valve opening (EVO),
- exhaust process (from EVO to EVC/IVO) and
- intake process (from IVO to IVC)
- During the combustion process, the mixture can be assumed to be
unburned and in expansion process (end of combustion to EVO), the
cylinder consists of burned gases.
December 10, 2013
ICAER-2013
Slide 6 of 32
7. MODEL DEVELOPMENT
MODEL DEVELOPMENT
- Spatial homogeneity of pressure for the whole cylinder, and spatial homogeneity of
temperature for each zone are considered.
- From IVC to EOC, the specific heats are calculated considering only fresh gases to
be present in the mixture and from EOC to EVC the properties are calculated
considering only burned gases.
- The gaseous mixture follows ideal gas law.
- It is assumed that exhaust valve closes at the instant the intake valve opens.
- Heat transfer is considered to happen only during the closed cycle operation i.e.
IVC to EVO.
- The Simulink model has following computation methodologies for determination
of various parameters;
December 10, 2013
ICAER-2013
Slide 7 of 32
8. MODEL DEVELOPMENT
MODEL DEVELOPMENT
Volume:
- Using the geometry parameters of the engines, the cylinder volume at any crank
angle by following relation;
π B2
2
V ( θ ) = Vc +
1 + a ( 1 − cos θ ) − l 2 − ( a sin θ )
÷
(1)
4
Heat release during combustion:
- The combustion investigation in engines has been carried out by analyzing cylinder
pressure data in single-zone thermodynamic model using Weibe function for
calculating heat release during combustion [6].
- A functional form often used to represent the mass fraction burned versus crank angle
curve [4].
θ − θ 0 m +1
(2)
X b = 1 − exp −a
÷
∆θ
- If δ Q is the heat released from combustion, it is computed from the following
relation;
0, θ ivc < θ ≤ θ 0 and θ > θ eoc
dQch
=
(3)
dx
dθ
Qmax b , for θ 0 < θ ≤ θ eoc
dθ
ch
December 10, 2013
ICAER-2013
Slide 8 of 32
9. MODEL DEVELOPMENT
MODEL DEVELOPMENT
- Here,
dxb
dθ
is the fuel mass burn rate which can be calculated from Weibe function
(Eq. 2). So the equation of mass burn fraction takes the following form;
m
θ − θ 0 m +1
dxb a ( m + 1) θ − θ 0
a
dθ
=
∆θ
÷ exp −a
÷
∆θ
∆θ
(4)
-Where,
is combustion completeness factor and tells about the efficiency of combustion;
-It depends upon the intensity of charge motion and engine design and falls in the range of
0.35 ≤ a ≤ 0.8
- ∆θ is the combustion duration
- m is the form factor that affects the shape of mass burned profile.
- These parameters determine the shape of Weibe function and hence its accuracy to
predict
the actual heat release during combustion.
December 10, 2013
ICAER-2013
Slide 9 of 32
10. MODEL DEVELOPMENT
MODEL DEVELOPMENT
Combustion duration:
- Total mass burned and the heat release are independent of the combustion duration (∆θ ).
- It is also very important factor because if same heat is released in small combustion
duration, the rate of heat release will be more and pressure peak would be higher as
compared to the large combustion duration. [7].
∆θ ( r , N , ϕ , θ ) = f ( r ) f ( N ) f ( ϕ ) f ( θ ) ∆θ
0
1
2
3
4
0
1
2
2
r
r
N
N
f1 ( r ) = 3.2989 − 3.3612 ÷+ 1.0800 ÷ ; f 2 ( N ) = 0.1222 + 0.9717 ÷+ 5.0510 × 10 −2 ÷
r1
r1
N1
N1
2
2
ϕ
ϕ
θ
θ
f3 ( ϕ ) = 4.3111 − 5.6393 ÷+ 2.3040 ÷ ; f 4 ( θ 0 ) = 1.0685 − 0.2902 0 ÷+ 0.2545 0 ÷
ϕ1
ϕ1
θ 01
θ 01
(5)
Cylinder temperature:
- The first law of thermodynamics applied to a closed volume of combustion chamber in
the following manner.
δ Qch = dU s + δ Qht + δW
dT
dθ
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=
⇒
δ Qch
dT dQht
dV
= mCv
+
+P
dθ
dθ
dθ
dθ
dV
dQch dQht
−
−P
mCv ( T ) dθ
dθ
dθ
1
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(7)
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11. MODEL DEVELOPMENT
MODEL DEVELOPMENT
Convective heat transfer rate:
- Using the Annand‘s correlation [2, 6] for convective heat transfer coefficient is obtained.
b
_
ρS B
_
hc B
p
÷ ; b = 0.7 and S p = 2aN ( mean piston speed )
=a
µ ÷
k
60
µ air
3.3 × 10 −7 × T 0.7
9γ − 5
µ=
=
; k=
µ Cv
Here
1 + 0.027ϕ
1 + 0.027ϕ
4
(8)
(9)
Pressure rise:
- Ideal gas law for closed cycle operation is used to obtain the pressure rise in the
combustion chamber. The ideal gas equation can be differentiated with respect to crank
angle.
P=
m0 RT
V
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⇒
dP
dθ
=
1
dT
dV
m0 R
−P
V
dθ
dθ
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12. MODEL DEVELOPMENT
MODEL DEVELOPMENT
Gas exchange process:
- In this process, the system is considered to be open system, from which gas can leave or
enter the system.. It is correlated with the valve opening area and pressure variation with
crank angle [8].
Aex = Aexo
dp
dθ
180 ( θ − θ evo )
sin
θ evc − θ evo
÷
1
3
180 ( θ − θ ivo )
; Ain = Aino sin
÷
720 + θ ivc − θ ivo
1
3
(11)
dp
RT dm p dV
1 dm 1 dV
−
;
= γ2 m
−
÷
÷
m dθ V dθ exhaust dθ
V dθ V dθ int ake
= γ1 p
Here, Aino and Aexo are maximum opening in intake and exhaust valves. Both the equations
require mass flow rate which are to be found from the equations of fluid mechanics.
Indicated torque and mean effective pressure:
- Indicated torque T ( θ ) as a function of crank angle [9] is obtained from the piston ( FP )
force by neglecting inertia of various components and friction.
Piston Force
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FP = ( p − patm )
n= l
sin 2θ
B2
Ap ; T ( θ ) = Fp a sin θ +
A =π
÷ ;
÷ (12)
2
2
a ; p
4
2 n − sin θ
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13. MODEL DEVELOPMENT
MODEL DEVELOPMENT
Indicated work done:
w.d . ( J ) =
ivc + 720
∫
ivc
Indicated Power:
P ( watt ) =
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dV
p(θ )
d
÷θ
dθ
w.d .
120
×N
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14. PROCEDURE OF SIMULATION
PROCEDURE OF SIMULATION
-Based on the above formulation for the zero-dimensional and single zone thermodynamic model
simulation, the Simulink model is being introduced for a four-stroke SI engine.
-This model has been built in solvers for ordinary differential equation, when the model is formulated
in appropriate logical manner. The flow chart of Simulink model is shown in Fig. 1.
- First, this Simulink model is validated with the experimental conditions for the engine as given in the
reference [8].
-Side by side, a CFD model has been developed for the combustion chamber of a test engine to predict
its performance (Fig. 2-a).
-It is a four-strokes, air cooled, 1.8HP (HONDA make) engine with rated speed of 3600 rpm (Table 1).
-In this model, one should be able to perform transient simulation with dynamic/moving mesh(Fig.2-b).
-For a fixed compression ratio, it uses a module “in-cylinder” using the commercial package Fluent 6.3.
-The premixed combustion model is used for simulating engine combustion for different speeds. The
performance results obtained from both the computational models are then compared.
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16. CFD MODEL
CFD MODEL
-
A 2-dimensional CFD model with
Axisymmetric swirl was made for the
new SI engine installed in Workshop.
-
The aim was to carry out the unsteady
simulation of the engine for closed cycle
period (IVC to EVO) and to obtain
pressure, temperature, and mass burn
fraction curve with crank angle.
-
The CFD model should be more
accurate because its solves conservation
equations for mass, momentum and
energy and also predicts combustion.
Fig.2 (a) 2-D geometry of
half combustion chamber
at clearance volume
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Fig.2 (b) Structured mesh of
cylinder at TDC (360 degree CA)
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17. CFD MODEL
CFD MODEL
•
Mesh Motion
Mesh is moved to crank angle corresponding to IVC i.e. 30 deg aBDC (570
deg.) as simulation would be setup from that crank angle.
Fig. 7 Clearance volume geometry
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18. CFD MODEL
CFD MODEL
Setting up the physics
•
Three user defined functions (UDFs) are used in this problem
1. Initialize.c : To initialize the flow field.
2. Laminar flame velocity.c: Function to calculate laminar flame speed at
different times.
3. work.c : to compute averaged values of pressure, temperature and mass
burn fraction.
•
Energy equation and turbulence are set on.
•
Premixed combustion model is used. Spark location and its timing is
specified.
•
Setting Boundary conditions and finally selecting solvers.
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19. ENGINE SPECIFICATIONS
ENGINE SPECIFICATIONS
Table 1 Specifications of engine
Sl. no
Specification
Simulink validation with
experimental results [8]
Simulink with
CFD validation
1
79.4
52
2
Bore ( B ) , mm
Stroke ( l ) , mm
111.2
46
3
Connecting rod (2a ), mm
233.4
81
4
Compression ratio (
7.4
4.8
5
Speed ( N ), rpm
4000 at 5 HP
3600 at 1.8HP
6
Spark timing ( º)
-25
-20
7
Intake manifold pressure ( Po ), atm
1
1
8
Relative Fuel-air ratio ( ϕ )
1
1
9
Fuel
C8H18 (Gasoline)
C8H18 (Gasoline)
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r)
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20. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
Validation of Simulink model
- Using the heat release rate obtained from experimental data [8], the
combustion duration for those operating conditions of experimental engine,
the reference values were found after tuning combustion model.
- At crank angles 25o before top dead centre (bTDC), the heat release rate
becomes zero and can be approximately taken as end of combustion so that the
combustion duration remains as 45o. The following reference parameters
obtained.
r1 = 9.2,
N1 = 4000 rpm,
ϕ1 = 1.1,
0
0
θ 01 = −20 and ∆θ1 = 45 .
- With this as input to the main Simulink model for simulating the cycle for any
operating condition.
- The parametric studies were done and results were compared with
experimental data
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21. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
(a)
(c )
Po=0.91 bar
(b)
Po=0.71 bar
(d)
Po=0.81 bar
Po=0.61 bar
Fig. 3 (a),(b),(c ) and (d) Variation of peak pressure with crank angle at different intake pressure
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22. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
Effect of intake pressure on performance with change in speed
Fig. 4 Thermal Efficiency and Power variation with speed
Fig. 5 Combustion heat release rate and pressure variation with speed
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23. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
Validation of CFD model
- HRR Analysis using Gasoline Experimental Data
Fig. 6 (a) and (b) pressure variation with crank angle using SIMULINK
Reference values for tuning combustion model are
r1 = 4.8,
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N 1 = 3600 rpm,
ϕ1 = 1,
0
0
θ01 = −20 and ∆θ1 = 140 .
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24. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
• Progress Variable (its value is 0 in unburned regions and 1 in burnt
regions).
Fig. 7 Clearance volume at end of suction stroke
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25. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
•
Progress variable at end of combustion for different rpm. We can find
combustion duration using contour plots as well.
Fig. 8 Combustion process at N=1000,2000.3000 rpm.
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26. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
-The CFD model is prepared using FLUENT was verified for its results at the condition
of rated power 1.8 HP at 3600 rpm.
- Simulink model which emulates the combustion could then be compared with results of
CFD model.
(b)
(a)
Fig. 9 (a) and (b) pressure and mass burn fraction variation with crank angle at N=1000 rpm.
December 10, 2013
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27. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
Fig. 10 (a) and (b) pressure and mass burn fraction variation with crank angle at N=2000 rpm.
Fig. 11 (a) and (b) pressure and mass burn fraction variation with crank angle at N=3000 rpm.
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28. RESULTS AND DISCUSSION
RESULTS AND DISCUSSION
- Brake power
Fig .12 Brake Power variation with speed
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29. CONCLUSIONS
CONCLUSIONS
- In this paper, an attempt has been made to address all the thermodynamic processes
occurring in engine through appropriate and suitable relations.
- A single-zone zero-dimensional Simulink model presents good interface to user.
- Side by side, the CFD analysis is also performed using commercial package (Fluent).
- In the present study, the Simulink model is validated from the experimental data and
found to be well agreement with the reported results.
- The Simulink analysis is performed to predict the maximum pressure after combustion.
- The deviation of mean pressure is about 6% higher as compared to experiment.
However, it reduces to 1% with reduction in intake charge pressure from 0.91 bar to
0.61 bar.
- During experiment, when the speed increases from 1000 to 4000 rpm, the heat release
rate rises from 3800 kJ to 4800 kJ, where as simulation shows constant heat release rate
of 2000 kJ for all speeds.
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30. CONCLUSIONS
CONCLUSIONS
- After successful validation of Simulink model, the numerical analysis was
carried out at rated rpm of engine (1.8 HP @ 3600 rpm) using CFD and
subsequently both the results are compared .
- Here, the pressure curve shows slight variation. At low speed 1000 rpm, the
maximum pressure recorded by CFD model showed relatively large deviation
(≥ 8%). But with increase in speed (at 3000 rpm), the variations reduces and
deviation remains below 3%.
- Mass burn fraction shows almost same trend of combustion duration. The
experimental brake power shows close match with Simulink and CFD results.
December 10, 2013
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31. REFERNCES
REFERNCES
[1] Ganesan, V. (2007) Internal Combustion Engines. Tata McGraw Hill, Third Edition.
[2] Wu, Y.Y., Chen B.C. and Hsieh, F.C. (2006) ‘Heat transfer model for small-scale air-cooled
spark-ignition four-stroke engines’. International Journal of Heat and Mass Transfer, Vol. 49,
pp.3895–3905
[3] Rakopoulos C.D. and Kyritsis D.C. (2005) ‘Hydrogen enrichment effects on the second law
analysis of natural and landfill gas combustion in engine cylinders’. International Journal of
Hydrogen Energy, Vol. 31, pp. 1384 – 1393
[4] Rakopoulos C.D., Michos C.N. and Giakoumis E.G. (2008) ‘Availability analysis of a syngas
fueled spark ignition engine using a multi-zone combustion model’. Energy, Vol. 33, pp.1378–
1398
[5] Ismail, S. and Mehta, P.S. (2011) ‘Second Law Analysis of hydrogen-air combustion in a spark
ignition engine’ International Journal of Hydrogen Energy, Vol. 36, pp.931 – 946
[6] Heywood, J.B. (1988) Internal Combustion Engine fundamentals. Tata McGraw Hill,
[7] Bayraktar, H. and Durgun, O. (2004) ‘Development of an empirical correlation for combustion
durations in spark ignition engines’. Energy Conversion and Management, Vol. 45, pp. 1419–
1431.
[8] Ganesan, V. (1996) Computer Simulation of Spark-Ignited Engine Process. Universities press
(India) Limited.
[9] Rattan, S. S. (2009) Theory of Machines. Third Edition, Tata McGraw Hill
December 10, 2013
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