Modelling and Control of Combustion Phasing of an Rcci Engine
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Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Dissertations, Master's Theses and Master's Reports - Open Reports 2015 MODELLING AND CONTROL OF COMBUSTION PHASING OF AN RCCI ENGINE Kaveh Khodadadi Sadabadi Michigan Technological University Follow this and additional works at: https://digitalcommons.mtu.edu/etds Part of the Mechanical Engineering Commons Copyright 2015 Kaveh Khodadadi Sadabadi Recommended Citation Khodadadi Sadabadi, Kaveh, "MODELLING AND CONTROL OF COMBUSTION PHASING OF AN RCCI ENGINE", Master's Thesis, Michigan Technological University, 2015. https://doi.org/10.37099/mtu.dc.etds/966 Follow this and additional works at: https://digitalcommons.mtu.edu/etds Part of the Mechanical Engineering Commons MODELLING AND CONTROL OF COMBUSTION PHASING OF AN RCCI ENGINE By Kaveh Khodadadi Sadabadi A THESIS Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE In Mechanical Engineering MICHIGAN TECHNOLOGICAL UNIVERSITY 2015 © 2015 Kaveh Khodadadi Sadabadi This thesis has been approved in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE in Mechanical Engineering. Department of Mechanical Engineering-Engineering Mechanics Thesis Advisor: Dr. Mahdi Shahbakhti Committee Member: Dr. Jeffery Naber Committee Member: Dr. Jeffery Burl Department Chair: Dr. William W. Predebon ii Contents List of Figures ................................................................................................................................... v List of Definitions/Abbreviations ..................................................................................................... viii List of Symbols ................................................................................................................................ xi List of Subscripts ............................................................................................................................ xiii Preface ........................................................................................................................................... xiv Acknowledgment ............................................................................................................................ xv Abstract .......................................................................................................................................... xvi Chapter 1 ......................................................................................................................................... 1 1.1 Motivation for Reactivity Controlled Combustion Strategy ............................................... 3 1.2 Charge stratification and RCCI combustion strategy ....................................................... 5 1.3 RCCI Combustion Strategy-Challenges ........................................................................ 13 1.4 Research Scope and Thesis Organization .................................................................... 14 Chapter 2 ....................................................................................................................................... 17 2.1 Introduction to COM development ................................................................................. 18 2.2 Modelling RCCI combustion........................................................................................... 24 2.2.1 SOC estimation model ............................................................................................... 26 2.2.2 Control oriented modelling of combustion duration.................................................... 34 2.2.1 CA50 estimation model .............................................................................................. 39 2.3 RCCI Engine Data .......................................................................................................... 40 2.4 Results and Discussion .................................................................................................. 44 2.4.1 Polytropic compression constant ............................................................................... 44 2.4.2 Parameterizing MKIM ................................................................................................. 45 2.4.3 BD Estimation............................................................................................................. 49 2.4.1 Estimation of CA50 .................................................................................................... 51 Chapter 3 ....................................................................................................................................... 55 3.1 RCCI Dynamic Model ..................................................................................................... 56 iii 3.1.1 Intake Stroke .............................................................................................................. 56 3.1.2 Compression Stroke ................................................................................................... 60 3.1.3 Combustion ................................................................................................................ 60 3.1.4 Expansion Stroke ....................................................................................................... 61 3.1.5 Exhaust Blow-down .................................................................................................... 61 3.1.6 Physical Model Lay-out .............................................................................................. 62 3.2 Controller Design ........................................................................................................... 64 3.2.1 Simplified COM .......................................................................................................... 64 3.2.2 Model Linearization and Linear Quadratic Integral (LQI) Design ............................... 68 3.2.3 State estimator performance ...................................................................................... 71 3.2.4 CA50 Tracking Results .............................................................................................. 73 3.2.5 Disturbance Rejection ................................................................................................ 74 Chapter 4 ....................................................................................................................................... 76 4.2 Summary and Conclusion .............................................................................................. 76 4.3 Suggestions for Future Work ......................................................................................... 78 References ..................................................................................................................................... 80 ..................................................................................................................................... 86 ..................................................................................................................................... 96 ..................................................................................................................................... 97 ..................................................................................................................................... 98 ................................................................................................................................... 100 iv List of Figures Figure 1-1. EPA green house gas (GHG) and fuel economy regulations. The data in reference [1] was used to produce this figure. ...................................................................................................... 2 Figure 1-2. ߮ versus temperature for CD and RCCI combustion at 5° aTDC [4] .......................... 10 Figure 1-3. Thesis structure. .......................................................................................................... 16 Figure 2-1. Control-oriented auto-ignition models for compression ignition combustion concepts 20 Figure 2-2. Charge preparation in RCCI combustion technology .................................................. 26 Figure 2-3. RCCI combustion phenomenological model (Formation of auto-ignition pockets and staged ignition). .............................................................................................................................. 26 Figure 2-4. Graphical integration of 1ݓ߬ from IVC to SOC ............................................................ 28 Figure 2-5. KIVA simulation and experimental results for 1 bar BMEP experiment. The data to generate this figure is taken from [10-11]. ..................................................................................... 42 Figure 2-6. KIVA simulation and experimental results for 2.6 bar BMEP experiment. The data to generate this figure is taken from [10-11]. ..................................................................................... 42 Figure 2-7. Estimated SOC pressures vs. SOC pressures from KIVA simulations using the best numerical fit of ݇ܿ=1.35. ݁ܽݒ݁, ߪܽݒ݁, ݁݉ܽݔ indicate average error, standard deviation of error and maximum error, respectively. ......................................................................................................... 44 Figure 2-8. MKIM SOC prediction and KIVA simulation Data........................................................ 46 Figure