摘要
以二甲醚(DME)为燃料基于柴油机实现均质充量压缩燃烧(HCCI)可以有效降低NOx和碳烟的排放,解决柴油供应日益紧张的局面,但存在燃烧不易控制,负荷范围窄的问题。使用缸内直喷柴油与进气道喷射DME两套喷射系统,在不同的工况下分别实现CIDI与HCCI两种燃烧方式,各取所长,是现阶段将HCCI实用化可行的技术方向。本文围绕双模式发动机的燃烧特点和模式切换过程的控制策略进行了模拟和实验研究。
本研究以气相计算软件包CHEMKIN为平台,采用敏感性分析法简化了DME和正庚烷的详细化学反应动力学机理,建立了用于分析HCCI和CIDI两种燃烧方式的三维模型,该模型以Fluent为计算平台,采用六面体网格,处理了活塞和气门运动的动网格,以离散相模型计算柴油喷雾过程,并将简化化学反应动力学机理耦合到三维模型中实现燃烧过程的模拟。模拟计算对比了两种燃烧方式各自的特点,预测了两种燃烧方式下的缸内温度分布,混合气浓度分布,HC以及NOx排放物分布,模拟结果与实验数据吻合。以三维模拟为基础,预测了适合HCCI燃烧的工况范围,为实验提供参考。
同时,基于Matlab-Simlink平台建立了用于控制策略仿真的发动机平均值模型。加入了用于预测HCCI燃烧过程燃烧始点和燃烧温度及燃烧放热率的模型,对柴油燃烧的求解则采用stick公式计算滞燃期长短,以双Vibe曲线模拟放热过程。基于该模型设计了模式切换过程的模糊控制策略,并同传统PID控制进行了比较。结果表明:模糊控制在动态特性上相比PID控制有优势,在切换工况点改变时,模糊控制的适应性较好,稳定性较强,鲁棒性好。
本研究构建了进气道电喷装置与电机油门驱动机构,设计了ECU控制单元与数据采集系统,实现了在进气道喷射二甲醚进行均质压燃(HCCI)和缸内直喷柴油(CIDI)两种燃烧模式。通过ECU控制进气道和缸内直喷两套喷油系统的喷油量,在临界工况点实现了CIDI-HCCI和HCCI-CIDI燃烧方式的切换。实验结果表明,在柴油机上实现模式切换时,前后循环间的依赖度较小,切换过渡时间较汽油机上实现SI-HCCI和HCCI-SI短,闭环控制在切换过程中有较好的适应性,能够满足转速在一定范围内波动的要求;而开环控制则更容易实现,应用于HCCI-CIDI模式切换时也能达到较理想的效果。
The HCCI (homogenous Charge Compression Ignition) combustion can reduce NOx and soot either by using the fuel dimethyl ether (DME). It can also resolve the increasingly tense situation in the supply of diesel oil. Meanwhile HCCI has the drawback of uncontrollable combustion phase and narrow work range. By the way of using both intake pipe injection and in-cylinder injection, HCCI and CIDI combustion can be implemented in different work point. This paper present the simulation and experiment research for dual-mode engine.
The numerical simulations based on the gas phase computation software CHEMKIN. Sensitivity analysis theory was used to get the reduced mechanism for both DME and n-heptane. A three-dimensional model was developed based on the diesel engine. The model use the hexahedral mesh to get the best quality, the movement of piston and valves were implemented. The discrete phase model was used for diesel oil injection, and the reduced mechanisms were coupled to compute the combustion process. The numerical simulation compared two combustion modes in temperature distribution, NOx distribution, the start of combustion and so on.
A mean value model was setup for simulation the mode transition strategy. The engine model contains the combustion start time and heat release rate model for HCCI and CIDI. The model uses the dual Vibe curve to compute the diesel oil combustion process, and uses stick formula to compute the ignition delay. A Fuzzy logic control strategy was designed. A PID control strategy was setup to compare Fuzzy Logic control. The results show that Fuzzy logic control strategy gets the better dynamic performance.
This research developed intake pipe injection system and motor-accelerator driven system. The ECU was designed for control the mode transition process. The experiment results show that cycle to cycle dependence is smaller than mode transition in gasoline engine, and close-loop control is more adaptive than open-loop control. But the open-loop control is easier to implement, it can also obtain the good transition process in the HCCI-CIDI mode transition.
引文
[1] http://www.energy.gov/
[2] http://www.bp.com/
[3] Addargarla, et al. Effect of Fuel-Air Mixture Stressing on Preignition Heat Release in a Knock Research Engine SAE Paper 892082
[4] Aoyama, et al. An Experimental Study on Premixed-Charge Compression Ignition Gasoline Engine. SAE Paper 960081
[5] Green R, et al. The Role of Low Temperature Chemistry in the Autoignition on N-Butane. SAE Paper 872108
[6] Fuquan Zhao,Thomas W Asmus,Demmis N Assanis,et al.Homogenecous Charge Compression Ignition(HCCI)Engines.SAE PT-94,2003
[7] A. Senatore and M. Cardone. A Comparative Analysis of Combustion Process in D. I. Diesel Engine Fueled with Biodiesel and Diesel Fuel. SAE Paper 2000-01-0691
[8] Hideyuki Ogawa, et al. Combustion Control and Operating Range Expansion With Direct Injection of Reaction Suppressors in a Premixed DME HCCI Engine. SAE Paper 2003-01-0746
[9] Zunqing Zheng, et al. Experimental Study on HCCI Combustion of Dimethyl Ether(DME)/Methanol Dual Fuel. SAE Paper 2004-01-2993
[10] Christensen, M.et al. Homogeneous Charge Compression Ignition (HCCI) Using Isooctane, Ethanol and Natural Gas- A Comparison with Spark Ignition Operation. SAE Paper 972874
[11] Zhili Chen,Mitsuru Konno.Experimental Study of CI Natural-Gas/DME Homogeneous Charge Engine.SAE 2000-01-0329
[12] Shigeru Onishi, et al. Active Thermo-Atmosphere Combustion (ATAC) - A New Combustion Process for Internal Combustion Engines. SAE Paper 790501
[13] Paul M. Najt, David E. Foster. Compression-Ignited Homogeneous Charge Combustion. SAE Paper 830264
[14] R. H. Thring. Homogeneous-Charge Compression-Ignition (HCCI) Engine. SAE Paper 892068
[15] Kengo Kumano, Norimasa lida. Anslysis of the Effect of Charge Inhomogeneity on HCCI Combustion by Chemiluminescence Measurement. SAE Paper 2004-01-1902
[16] Masaaki Noguchi, Yukiyasu Tanaka. A Study on Gasoline Engine Combustion By Observation of intermediate Reactive Products During Combustion. SAE Paper 790840
[17] Magnus Christensen,Anders Hultqvist,Bengt Johansson.Demonstrating the Multi Fuel Capability of a Homogeneous Charge Compression Ignition Engine with Variable Compression Ratio.SAE 1999-01-3679
[18] Haraldsson G.HCCI combustion phasing in a multi cylinder engine using variable compression ratio. SAE 2002-01-2858
[19] Hyvonen. Balancing Cylinder-to Cylinder Variations in a Multi-Cylinder VCR-HCCI Engine. SAE 2004-01-1897
[20] P. G. Aleiferis, et al. Modelling and Experiments of HCCI Engine Combustion with Charge Stratification and Internal EGR. SAE Paper 2005-01-3725
[21] A. Dubreuil, et al. Effect of EGR Chemical Components and Intake Temperature on HCCI Combustion Development. SAE Paper 2006-32-0044
[22] Song-Charng Kong, Amar Patel. Numerical Modeling of Diesel Engine Combustion and Emissions Under HCCI-Like Conditions With High EGR Levels. SAE Paper 2003-01-1087
[23] Fredrik Agrell.Transient Control of HCCI Through Combined Intake and Exhaust Valve Actuation.SAE 2003-01-3172
[24] Fredrik Agrell.Control of HCCI During Engine Transients by Aid of Variable Valve Timings Through the Use of Model Based Non-Linear Compensation.SAE 2005-01-0131
[25] Petter Strandh,Johan Bengtsson,Rolf Johansson,et al.Variable Valve Actuation for Timing Control of a Homogeneous Charge Compression Ignition Engine. SAE 2005-01-0147
[26] Jan-Ola Olsson, Per Tunestal, and Jonas Ulfvik. The Effect of Cooled EGR on Emissions and Performance of a Turbocharged HCCI Engine. SAE Paper 2003-01-0743
[27] Lucien Koopmans, et al. A Four Stroke Camless Engine, Operated in Homogeneous Charge Compression Ignition Mode with Commercial Gasoline. SAE Paper 2001-01-3670
[28] Nicos Ladommatos, et al. Effects of Air/Fuel Ratios and EGR Rates on HCCI Combustion of n-heptane, a Diesel Type Fuel. SAE Paper 2003-01-0747
[29] Olsson J.A turbo charged dual fuel HCCI engine. SAE 2001-01-1896
[30] Amit Bhave,Markus Kraft.Evaluating the EGR-AFR Operating Range of a HCCI Engine. SAE 2005-01-0161
[31] Magnus Christensen, Bengt Johansson. Homogeneous Charge Compression Ignition with Water Injection. SAE Paper 1999-01-0182
[32] Magnus Christensen, et al. Supercharged Homogeneous Charge Compression Ignition (HCCI) with Exhaust Gas Recirculation and Pilot Fuel. SAE Paper 2000-01-1835
[33] Magnus Christensen, et al. The Effect of Combustion Chamber Geometry on HCCI Operation. SAE Paper 2002-01-0425
[34] G Gnanam,M Johnson,A Sobiesiak,et al.HCCI Combustion With Internal Fuel Reforming,Varied Levels of EGR and Charge Preheat-A Computational Study. SAE 2005-01-0140
[35] Persson, et al. The Effect of Intake Temperature on HCCI Operation Using Negative Valve Overlap. SAE Paper 2004-01-0944
[36] Thomas W, et al. Homogeneous Charge Compression Ignition of Diesel Fuel. SAE Paper 961160
[37] Arjan Helmantel, et al. HCCI Operation of a Passenger Car Common Rail DI Diesel Engine With Early Injection of Conventional Diesel Fuel. SAE Paper 2004-01-0935
[38] Lucien Koopmans, Staffan Lundgren, Ove Backlund, etc. Demonstrating a SI-HCCI-SI Mode Change on a olvo 5-Cylinder Electronic Valve Control Engine. SAE Paper 2003-01-0753
[39] A. Fuerhapter, et al. The new AVL CSI Engine– HCCI Operation on a Multi Cylinder Gasoline E ngine. SAE Paper 2004-01-0551
[40] Haraldsson, et al. Transient Control of a Multi Cylinder HCCI Engine During a Drive Cycle. SAE Paper 2005-01-0153
[41] Jari, et al. Operating Conditions Using Spark Assisted HCCI Combustion During Combustion Mode Transfer to SI in a Multi-Cylinder VCR-HCCI Engine. SAE Paper 2005-01-0109
[42] Nebojsa Milovanovic, et al. SI-HCCI-SI Mode Transition at Different Engine Operating Conditions. SAE Paper 2005-01-0156
[43] Junichi Kamio, et al. Study on HCCI-SI Combustion Using Fuels Ethanol Containing. SAE Paper 2007-01-4051
[44] Tsuyoshi Matsuda, et al. A Study of a Gasoline-fueled HCCI Engine～ModeChanges from SI Combustion to HCCI Combustion. SAE Paper 2008-01-0050
[45] Hiromu Kakuya, et al. Investigation of a SI-HCCI Combustion Switching Control Method in a Multi-Cylinder Gasoline Engine. SAE Paper 2008-01-0792
[46] Hao Wu, et al. Experimental Investigation of a Control Method for SI-HCCI-SI Transition in a Multi-Cylinder Gasoline Engine. SAE Paper 2010-01-1245
[47] Hongming Xu, Simon Rudolph, Zhi Liu,et al. An Investigation into the Operating Mode Transitions of a Homogeneous Charge Compression Ignition Engine Using EGR Trapping. SAE Paper 2004-01-1911
[48] Hongming Xu,Michael Liu,Shadi Gharahbaghi.Modelling of HCCI Engines:Comparison of Single-zone,Multi-zone and Test Data.SAE 2005-01-2123
[49] Shazam Williams, Linjie (Robin) Hu, Tohru Nakazono. Oxidation Catalysts for Natural Gas Engine Operating under HCCI or SI Conditions. SAE Paper No. 2008-01-0807
[50] Jonathan Etheridge, et al. A Fast Detailed-Chemistry Modelling Approach for Simulating the SI-HCCI Transition. SAE Paper 2010-01-1241
[51]田国宏,王志,等.缸内直喷汽油机SI-HCCI-SI燃烧模式切换的研究.内燃机学报,2007(3): 229~234.
[52] Yan Zhou, et al. Study of SI-HCCI-SI Transition on a Port Fuel Injection Engine Equipped with 4VVAS. SAE Paper 2007-01-0199
[53] Nenghui Zhou, et al. Study on Layered Close Loop Control of 4-Stroke Gasoline HCCI Engine Equipped with 4VVAS. SAE Paper 2008-01-0791
[54] Xie Hui, et al. Control Strategies for Steady and Transient Operation of a 4-Stroke Gasoline Engine with CAI Combustion Using a 4-Variable Valve Actuating System (4VVAS). SAE Paper 2006-01-1083
[55]张岩,谢辉等. 4VVAS双模式发动机SI_HCCI燃烧模式过渡研究.内燃机学报,2008(1): 29~35
[56]周能辉,谢辉等. HCCI_SI双模式汽油机全可变气门控制的研究.内燃机学报,2007(5): 396~401
[57]彭亚平,郭英男等.双燃烧模式发动机性能和排放特性对比的试验研究,内燃机学报,2007(4): 334~338
[58]郭英男,彭亚平等.乙醇燃料SI-HCCI-SI燃烧模式转换过程的研究,内燃机学报,2007(4): 311~315
[59] PENG YaPing, TAN ManZhi, et al. Study the Ethanol SI/HCCI Combustion ModeTransition by Using the Fast Thermal Management System. Chinese Science Bulletin,October 2007,Vol.52,No.19: 2731~2736
[60]彭亚平,郭英男.火花点火对乙醇燃料SI/HCCI燃烧模式转换平稳性的影响.燃烧科学与技术,2007,Vol.13,No.6 521~524.
[61] Cristian Musardo, Benedetto Staccia, et al. Supervisory Control for NOx Reduction of an HEV with a Mixed-Mode HCCI/CIDI Engine. Ceistian Musardo, Benedetto Staccia 2005 American Control Conference: 3877~3881
[62] M. Canova, F. Chiara, et al. Experimental Characterization of Mixed-Mode HCCI/DI Combustion on a Common Rail Diesel Engine. SAE Paper 2007-24-0085
[63] Kushal Narayanaswamy and Christopher J. Rutland, et al. A Modeling Investigation of Combustion Control Variables During DI-Diesel HCCI Engine Transients. SAE Paper 2006-01-1084
[64] Chemkin-Tutorials Manual.Reaction design.
[65] Chemkin-Theory Manual.Reaction design.
[66]谢茂昭.内燃机计算燃烧学(第二版).大连:大连理工大学出版社. 2005. P283~321.
[67] G Wochini.A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine. SAE 670931
[68] Kaiser, E.W., Curran, H. J., et al.Experimental and Modeling Study of Premixed Atmospheric-Pressure Dimethyl Ether-Air Flames[C].Journal of Physical Chemistry A,2000,104 (35):8194-8206
[69] Hiroyuki Yamada, Hideki Sakanashi, Namil Choi, et al. Simplified Oxidation Mechanism of DME Applicable for Compression Ignition. SAE Paper 2003-01-1819
[70] Hyunguk Kim, Sungwoo Cho, Kyoungdoug Min. Reduced Chemical Kinetic Model of DME for HCCI Combustion. SAE Paper 2003-01-1822
[71]石宇,张煜盛,莫春兰. DME简化反应模型及其在HCCI燃烧分析中的应用研究.安全与环境学报. 2006. Vol.6 No.2
[72] W.J.Pitz, H.J.Curran. Extinction and Autoignition of n-Heptane in Counterflow Configuration. Twenty-Eighth International Symposium on Combustion University of Edinburgh. 2000.
[73] Li T S, McKeag R M, Armst rong C G.Hexahedral meshing using midpoint subdivision and integer programming[J] . Computer M ethods in Applied Mechanics and Engineering, 1995, 124 (2): 171- 193
[74] Sheffer A, Et zion M, Rappoport A, et al. Hexahedral mesh generation using the embedded voronoi graph[J] . Engineering with Computers, 1999(15): 248-262
[75] Liu S S , Gadh R. Basic logical bulk shapes(BLOBs) for finite element hexahedral mesh generation [J].Journal of Manufacturing Science and Engineering, 1998, 120(4): 728-735
[76] HyperWorks User Manual. HyperWorks Company. 2005
[77]潘述文.液体粒子的光电测量-喷雾粒子直径的测量方法和柴油机的喷雾粒子直径分布.小型内燃机与摩托车. 1980 (1): 38~54
[78]文华.基于CFD的柴油机喷雾混合过程的多维数值模拟:[博士学位论文].华中科技大学图书馆,2005
[79]刘金武. HSDI柴油机雾化与排放特性瞬态多维建模和数值研究:[博士学位论文].湖南大学图书馆,2007
[80] Fluent User’s Guide. Fluent Int.
[81] On the Structure of Turbulence and a Generalized Eddy Dissipation Concept for Chemical Reaction in Turbulent Flow.
[82]莫春兰,张煜盛,石宇.二甲基醚发动机HCCI燃烧与排放的计算.华中科技大学学报(自然科学版). 2006(11): 103~105.
[83] Livengood, J. C, and Wu, P. C. Correlation of Autoignition Phenomena in Internal Combustion Engines and Rapid Compression Machines. 1955 5th Symposium on Combustion.
[84] Per Risberg. Describing the Auto-Ignition Quality of Fuels in HCCI Engines. Doctoral thesis of KTH, 2006
[85] D. J. Rausen, et al. A Mean-Value Model for Control of Homogeneous Charge Compression Ignition (HCCI) Engines. Journal of Dynamic Systems, Measurement, and Control SEPTEMBER 2005, Vol. 127: 355~362
[86] Fredrik Agrell, et al. Integrated Simulation and Engine Test of Closed Loop HCCI Control by Aid of Variable Valve Timings. SAE Paper 2003-01-0748
[87]朱访君.内燃机工作过程数值计算及其优化.北京:国防工业出版社,1997
[88] L.A.Zadeh. Fuzzy Set. Information and Control. 1965, Vol 8, 338~353
[89] L.A.Zadeh. Fuzzy Algorithm. Information and Control. 1968, Vol 12, 94~102
[90] King P J et al. The Application of Fuzzy Control Systems to Industrial Process. IFAC World Congress. MIT. Boston. 1975
[91] Tong R M. Synthesis of Fuzzy Models for Industrial Process. Int. Gen. Sys 1978, 4:143~162
[92] Tong R M. An annotated bibliography of Fuzzy control in industrial application of fuzzy control sugeno M ed. Amsterdam North-Holland, 1985
[93] Tong R M. A Control Engineering Review Fuzzy Systems. Automat, 1977, 13 (6): 559~569
[94] Tong R M. Fuzzy control of the activated sludge wastewater treatment process. Automat, 1980,16 (6):695~701
[95] Ostergarad J J. Fuzzy logic control of a heat exchange process in fuzzy automata and decision process. Amsterdam Gupta MM. et. eds. North-Holland, 1977
[96] Pappis C P, et al. A fuzzy logic controller for a traffic junction. IEEE Trans. on SMC, 1977, SMC-7 (10): 707~717
[97] E.H.Mamadani.Applications of Fuzzy Algorithms for Control of Simple Dynamic Plant. Proc. IEEE.1974, P1585~1588
[98] T.Takagi,M.Sugeno.Fuzzy identification of systems and its applications to modeling and control.IEEE Trans.Systems Man Cybernetics.1985,15:116~132
[99]王辉,肖建,严殊.关于模糊系统辨识近年来的研究与发展.信息与控制. 2004,33(4):445~450
[100]Mamdani E.Application of fuzzy logic to approximate reasoning using linguistic systems.Fuzzy sets and systems.1977,26:1182~1191
[101]Yi S,Chung M.Identification of fuzzy relational model and its application to control.Fuzzy sets and systems,1993,59:25~33
[102]Wang L,Langari R.Complex systems modeling via fuzzy logic.IEEE Trans.Systems,Man and Cybernetics. 1996, 26(1):100~106
[103] Jin Y C, Zhu J, et al. Adaptive Fuzzy Modeling and Identification with Its Application. International Journal of Systems Science, 1995, 26 (2): 197~212
[104]Xie W F. Fuzzy Adaptive Internal Model Control . IEEE Tran. on Industrial Electronics, 2000, 47 (1): 193~202
[105]吴方晖.基于神经网络的带遗传算法的模糊控制器.华南理工大学学报(自然科学版),1999,27 (1): 91~95
[106]Macro R. A Fuzzy Genetic Neural System for Fuzzy Modeling. IEEE Trans. on Fuzzy Systems, 1998,6 (3): 373~387
[107]刘增量.模糊逻辑与神经网络—理论研究与探索.北京:北京航空航天出版社,1996
[108]Scarselli F. Universal Approximation Using Feed-Forward Neural Networks a Survery of some Methods and some New Results. Neural Networks, 1998, 9 (6): 15~37
[109]Jin Y C, Zhu J, et al. Netural Network Based Fuzzy Identification and Its APllication to Modeling and Control of Complex Systems. IEEE Tran. On SMC, 1995, 25 (6): 990~997
[110]Takagi H. Neural Networks Designed on Approximate Reasoning Architecture and Their Applications. IEEE. Trans, on Neural Network, 1992, 3 (5): 752~760
[111]Ksoko B. Neural Network and Fuzzy Systems: A Dynamical Approach to Machine Intelligence. Englewood Cliffs. NJ: Prentice-Hall. 1992
[112]Mamdani E.Application of fuzzy logic to approximate reasoning using linguistic systems.Fuzzy sets and systems.1977,26:1182~1191
[113] Togai M, Watanabe H. Expert System on A Chip: An Engine for Real-time Approximate Reasoning. IEEE System Magazine, 1986, 1
[114]Yamakawa T. Fuzzy Microprocessor-rule Chip and Defuzzifier Chip. Workshop on Fuzzy System, Application. Lizuka, Japan, 1988: 51~52
[115]Zadeh L A. A Rationale for Fuzzy Control. Trans. ASME J. Dynamic System Measure Control, 1972
[116]Hirota H, Pedrycz W. Analysis and Synthesis of Fuzzy Systems by The Use of Fuzzy Sets. Fuzzy Sets and Systems, 1983, 10 (1): 1~14
[117]Ross, T.J. Fuzzy logic with Engineering Application. The McGraw-Hill Companies, Inc. 1995
[118]诸静.模糊控制原理与应用.北京:机械工业出版社,2005:303~322
[119]张文修.模糊控制与模糊系统.西安:西安交通大学出版社,1998
[120]胡寿松.自动控制原理(第四版).北京:科学出版社,2001
[121]刘金琨.先进PID控制MATLAB仿真(第二版).北京:电子工业出版社,2004
[122]PCIS-DASK Function Reference Manual. ADLink Technology Inc. 2003
[123]PCIS-DASK Data Acquisition Software Development Kit For NuDAQ PCI-bus Cards, Windows NT/98/2000 User’s Guide
[124]Microsoft Developper Network– Visual Studio 2008. Microsoft Company. Inc.
[125]李明友.单缸汽油机振动噪声的分析和控制:[硕士学位论文].重庆大学图书馆,2007
[126]卫海桥.直喷式柴油机瞬态工况燃烧噪声激励机理研究:[博士学位论文].天津大学图书馆,2004
[127]李兆文.柴油机燃烧噪声影响机理及控制研究:[硕士学位论文].天津大学图书馆,2009
[128]孙少军.重型车用发动机振动与噪声控制的理论与应用研究:[博士学位论文].天津大学图书馆,2008
[129]Santoso H, Matthews, and Cheng, W.K. Managing SI/HCCI Dual-Mode Engine Operation. SAE Paper 2005-01-0162