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The Impact of Water Injection on Spark Ignition Engine Performance Under High Load Operation

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The Impact of Water Injection on Spark Ignition Engine Performance Under High Load Operation Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Reports 2017 THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION Jeremy Worm Michigan Technological University, [email protected] Copyright 2017 Jeremy Worm Recommended Citation Worm, Jeremy, "THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION", Open Access Dissertation, Michigan Technological University, 2017. https://digitalcommons.mtu.edu/etdr/552 Follow this and additional works at: https://digitalcommons.mtu.edu/etdr Part of the Energy Systems Commons, Heat Transfer, Combustion Commons, and the Other Mechanical Engineering Commons THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION By Jeremy Worm A DISSERTATION Submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY In Mechanical Engineering-Engineering Mechanics MICHIGAN TECHNOLOGICAL UNIVERSITY 2017 © 2017 Jeremy Worm This dissertation has been approved in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY in Mechanical Engineering-Engineering Mechanics. Department of Mechanical Engineering – Engineering Mechanics Dissertation Advisor: Dr. Jeffrey D. Naber Committee Member: Dr. Darrell Robinette Committee Member: Dr. Jason Blough Committee Member: Dr. Scott Wagner Department Chair: Dr. William W. Predebon Dedication I dedicate this dissertation to my loving wife Jennifer. Without her unwavering support and encouragement this would not have come to completion. Contents 1 Introduction .................................................................................................................1 1.1 Load Control in SI Engines ..............................................................................1 1.2 Methods of Increasing Load .............................................................................3 1.2.1 Increased Displacement ......................................................................4 1.2.2 Increased Pressure (Boosting).............................................................4 1.2.3 Limitations of Boosting ......................................................................4 1.2.4 Auto-Ignition Mitigation Techniques .................................................5 1.3 Motivation ........................................................................................................8 1.4 Goals and Objectives ......................................................................................10 2 Literature Review......................................................................................................12 2.1 Trends in Downsizing and Boosting ..............................................................12 2.2 Water Injection ...............................................................................................21 2.2.1 Water Injection Effects on Knock.....................................................23 2.2.2 Water Injection Effects on Volumetric Efficiency ...........................26 2.2.3 Water Injection Effects on Compression Work ................................27 2.2.4 Water Injection Effects on Expansion Work ....................................29 2.2.5 Water Injection Effects on Combustion ............................................30 2.2.6 Water Injection Effects on Ideal Cycle Efficiency ...........................31 2.2.7 Summary of Existing Literature........................................................31 3 Research Methodology .............................................................................................33 3.1 Base Engine ....................................................................................................33 3.2 Fuels ...............................................................................................................34 3.3 Experimental Test Matrix ...............................................................................36 3.4 Simulation Test Matrix ...................................................................................39 4 Experimental Setup ...................................................................................................42 4.1 Using Simulation Results in Testbed Build ...................................................42 4.2 Experimental Test Bed ...................................................................................44 4.2.1 ESN01 ...............................................................................................44 4.2.2 ESN02 ...............................................................................................45 4.2.3 Fasteners ...........................................................................................45 4.2.4 Pistons ...............................................................................................47 4.2.5 Fuel Pump .........................................................................................53 4.2.6 Intake Cam ........................................................................................58 4.2.7 Exhaust Cam .....................................................................................59 4.2.8 Valve Springs ....................................................................................60 iv 4.2.9 Connecting Rods ...............................................................................63 4.2.10 Throttle Body ....................................................................................63 4.2.11 Boosting System ...............................................................................63 4.2.12 Lubrication Oil ..................................................................................80 4.2.13 Water Injection System .....................................................................83 4.3 Controls ..........................................................................................................85 4.3.1 Water Injection Control ....................................................................85 4.3.2 Engine Control ..................................................................................87 4.4 Instrumentation ...............................................................................................96 4.4.1 Test Cell ............................................................................................96 4.4.2 Combustion Analysis ........................................................................96 4.5 Water Supply System ...................................................................................109 4.6 Supplemental Support Systems ....................................................................114 4.6.1 Fuel System .....................................................................................114 4.6.2 Cooling System ...............................................................................117 4.6.3 Engine Crank Case Ventilation .......................................................117 4.6.4 Test Cell Ventilation .......................................................................119 4.6.5 Engine Exhaust ...............................................................................119 5 Key Metrics Used for Analysis ...............................................................................121 6 Results .....................................................................................................................127 6.1 Preliminary Testing ......................................................................................127 6.1.1 Engine Break-In ..............................................................................127 6.1.2 Measurement Checks ......................................................................128 6.1.3 Baseline Checks ..............................................................................131 6.1.4 Water SOI Sweeps ..........................................................................136 6.2 Water Injection Testing Results ...................................................................143 6.2.1 Production Boost Levels .................................................................143 6.2.2 Test Results at 300 kPa MAP .........................................................177 6.3 Water Vaporization ......................................................................................184 6.3.1 Water Vaporization during Intake and Compression ......................184 6.3.2 Water Vaporization during Combustion and Expansion ................194 6.4 Enthalpy Effects ...........................................................................................198 6.5 Impact of the Timing of Water Vaporization ...............................................201 7 Hardware Failures and Issues .................................................................................203 7.1 Water Pump Drive System ...........................................................................203 7.2 Oil Cooler .....................................................................................................204 7.3 Spark Plugs ...................................................................................................204 v 7.4 Ignition Coil .................................................................................................205 7.5 Throttle Body ...............................................................................................205 7.6 Optical Encoder ............................................................................................206
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