Reciprocating Internal Combustion Engines
Reciprocating Internal Combustion EnginesProf. Rolf D. Reitz,Engine Research Center,University of Wisconsin-Madison2012 Princeton-CEFRCSummer Program on CombustionCourse Length: 9 hrs(Wed., Thur., Fri., June 27-29)Hour 1Copyright 2012 by Rolf D. Reitz.This material is not to be sold, reproduced or distributed withoutprior written permission of the owner, Rolf D. Reitz.1CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingShort course outine:Engine fundamentals and performance metrics, computer modeling supportedby in-depth understanding of fundamental engine processes and detailedexperiments in engine design optimization.Day 1 (Engine fundamentals)Hour 1: IC Engine Review, 0, 1 and 3-D modelingHour 2: Turbochargers, Engine Performance MetricsHour 3: Chemical Kinetics, HCCI & SI CombustionDay 2 (Spray combustion modeling)Hour 4: Atomization, Drop Breakup/CoalescenceHour 5: Drop Drag/Wall Impinge/VaporizationHour 6: Heat transfer, NOx and Soot EmissionsDay 3 (Applications)Hour 7: Diesel combustion and SI knock modelingHour 8: Optimization and Low Temperature CombustionHour 9: Automotive applications and the Future2CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingMotivationSociety relies on IC engines for transportation, commerce and power generation:utility devices (e.g., pumps, mowers, chain-saws, portable generators, etc.),earth-moving equipment, tractors, propeller aircraft, ocean liners and ships,personal watercraft and motorcyclesICEs power the 600 million passenger cars and other vehicles on our roads today.250 million vehicles (cars, buses, and trucks) were registered in 2008 in US alone.50 million cars were made world-wide in 2009, compared to 40 million in 2000.China became the world’s largest car market in 2011.A third of all cars are produced in the European Union, 50% are powered diesels. IC engine research spans both gasoline and diesel powerplants.Fuel Consumption70% of the roughly 86 million barrels of crude oil consumed daily world-wide isused in IC engines for transportation.10 million barrels of oil are used per day in the US in cars and light-duty trucks4 million barrels per day are used in heavy-duty diesel engines,- total oil usage of 2.5 gallons per day per person.Of this, 62% is imported (at 80/barrel - costs US economy 1 billion/day).3CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingUS Energy Flow ChartWorld energy use 500 x 1018 J14EJ23EJ23EJ70% of liquidfuel used otalenergy/428% of totalUS energyconsumptionCEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingFuel consumption - CO2 EmissionsWorld oil use: 86 million bbl/day 3.6 billion gal/day ( 0.6 gal/person/day)Why do we use fossil fuels (86% of US energy supply)?Large amount of energy is tied up in chemical bonds.Consider stoichiometric balance for gasoline (Octane) in air:C8H18 12.5(O2 3.76N2) 8CO2 9H2O 47N2 ( 48x106 J/kgfuel)Kinetic energy of 1,000 kg automobile traveling at 60 mph (27 m/s) 1/2·1,000·272 (m2 kg/s2 Nm) 0.46x106 J energy in 10g gasoline 1/3 oz (teaspoon)Assume:1 billion vehicles/engines, each burns 2.5 gal/day (1 gal 6.5lb 3kg) 7.5x109 kgfuel/day*48x106 J/kg 360x1018 J/yr1 kg gasoline makes 8·44/114 3.1 kg CO2 365 · 7.5x109 kgfuel/yr 8,486x109 kg-CO2/year 8.5x109 tonne-CO2/year(Humans exhale 1 kg-CO2/day 2x109 tonnes-CO2/yr)Total mass of air in the earth’s atmosphere 5x1018 kgSo, CO2 mass from engines/year added to earth’s atmosphere8.5x1012 / 5x1018 1.7 ppm5CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modeling1%(Prof. JohnHeywood, MIT)Modern gasoline IC enginevehicle converts about16% of the chemicalenergy in gasoline touseful work.The average light-duty vehicleweighs 4,100 lbs.The average occupancy of alight-duty vehicle is 1.6persons.If the average occupantweighs 160 lbs,0.16x((1.6x160)/4100) 0.016CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingPollutant Emissions37 billion tons of CO2 (6 tons each for each person in the world) from fossil fuels/yr,plus other emissions, including nitric oxides (NOx) and particulates (soot).CO2 contributes to Green House Gases (GHG), implicated in climate change- drastic reductions in fuel usage required to make appreciable changes in GHGCO2 emissions linked to fuel efficiency:- automotive diesel engine is 20 to 40% more efficient than SI engine.But, diesels have higher NOx and soot.- serious environmental and health implications,- governments are imposing stringent vehicle emissions regulations.- diesel manufacturers use Selective Catalytic Reduction (SCR) after-treatmentfor NOx reduction: requires reducing agent (urea - carbamide) at rate (and cost) ofabout 1% of fuel flow rate for every 1 g/kWh of NOx reduction.Soot controlled with Diesel Particulate Filters (DPF),- requires periodic regeneration by richening fuel-air mixture to increase exhausttemperature to burn off the accumulated soot- imposes about 3% additional fuel penalty.Need for emissions control removes some of advantages of the diesel engine7CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingNew directionsNew technologies urgently needed to improve efficiency of gasoline and diesels.Engines need to be optimized to balance emissions, fuel cost, and marketcompetitiveness.Advanced CFD models and optimization methods increasingly used by the industry.- made possible by dramatic increases in computer speeds (x104 in last 15 years)- significantly reduces requirements for expensive experimental testingDevelopment of predictive models for engine physical processes has been anadditional enabling factor for engine design- CFD tools are mature enough to guide the development of more efficient andcleaner internal combustion engines.New low temperature combustion (LTC) concepts, such as:Homogeneous Charge Compression Ignition (HCCI),Premixed Charge Compression Ignition (PCCI) andReactivity Controlled Compression Ignition (RCCI)offer promise of dramatically improved engine efficiencies- can be explored/optimized with CFD tools.8CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingBrief history of engine CFDArab oil crisis 1973: US DOE Open source codes– Los Alamos National Lab, Princeton Univ., UW-ERC– 1970’s – RICE REC APACHE CONCHAS– 1980’s – CONCHAS-SPRAY KIVA family– 1985 – KIVA ;1989 – KIVA-II; 1993 – KIVA-3;– 1997 – KIVA-3V; 1999 – KIVA-3V Release 2; 2006 - KIVA-4– 2004 – OpenFOAM (2011 SGI)Commercial codes– 1980’s Imperial College & others– Computational Dynamics, Ltd. commercialize: STAR-CD– 1990’s—other commercial codes: AVL FIRE, Ricardo VECTIS– 2005– FLUENT (with moving piston and in-cylinder models)– 2010 – CONVERGE (CSI), FORTE (Reaction Design) .22nd Annual IMEM-User group meeting: Cray/UW-ERC 2012ILASS, SAE Congress Multidimensional Modeling Session9CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingGoal of IC Engine:Convert energy contained in a fuel into useful work, as efficiently and costeffectively as possible.Identify energy conversion thermodynamics that governs reciprocating engines.Describe hardware and operating cycles used in practical IC engines.Discuss approaches used in developing combustion and fuel/air handling systems.Internal Combustion Engine developmentRequires control to:introduce fuel and oxygen, initiate and control combustion, exhaust productsIC engine(Not constrained byCarnot cycle)Heat (EC) engine(Carnot cycle)Energy releaseoccurs externalHeat sourceto the system.Working fluidundergoesreversible statechanges (P,T)Heat sinkduring a cycle(e.g., Rankine cycle)OxygenWorkWorkFuel10Energy releaseoccurs internalto the system.Working fluidundergoes state(P,T) and chemicalchangesduring a cycleCombustion productsCEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingComponents of piston enginePiston moves between Top Dead Center (TDC) and Bottom Dead Center (BDC).Compression Ratio CR ratio of BDC/TDC volumesStroke S travel distance from BDC to TDCBore B cylinder diameterD Displacement (BDC-TDC) volume.# cylinders p B2 S/4 . # cylindersBasic EquationsP W.N T.NP [kW] T [Nm].N [rpm].1.047 E-04BMEP P.(rev/cyc) / D.NBMEP [kPa] P [kW].(2 for 4-stroke) E03/ D [l]. N [rev/s]BSFC mfuel / PBSFC mfuel [g/hr] / P [kW].Brake gross indicated pumping friction net indicated friction11P (Brake) Power [kW]T (Brake) Torque [Nm] Work WBMEP Brake mean effective pressuremfuel fuel mass flow rate [g/hr]BSFC Brake specific fuel consumption.CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingEngine PowerHeywood, 1988Indicated power of IC engine at a given speed.is proportional to the air mass flow rate, mair.P hf . mair N. LHV . (F/A) / nrhf fuel conversion efficiencyLHV fuel lower heating valueF/A fuel-air ratio mf/mairnr number of power strokes / crank rotation 2 for 4-strokeEfficiency estimates:hf 1/46 MJ/kg / 200 g/kW-hr 40-50%SI:270 bsfc 450 g/kW-hrDiesel: 200 bsfc 359 g/kW-hr 500 MW GE/Siemens combined cycle gas turbine natural gaspower plant 60% efficient12CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modeling4-stroke (Otto) cycle“Suck, squeeze, bang, blow”1. Intake:piston moves from TDC to BDCwith the intake valve open,drawing in fresh reactantsWin, gross 1802. Compression:valves are closed and piston movesfrom BDC to TDC,Combustion is initiated near TDCpdv BDCpdvBDC3(net gross pumping)Win,net 3. Expansion:high pressure forces pistonfrom TDC to BDC, transferring workto crankshaft4. Exhaust:exhaust valve opens and piston movesfrom BDC to TDC pushing out exhaust 180 pdv214TDC1,4 Pumping loop – An additionalrotation of the crankshaft used to:- exhaust combustion products- induct fresh chargeBDCFour-stroke diesel pressure-volumediagram at full load13CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingCombustion process - initiated near end of compression stroke.Instantaneous combustion has high theoretical efficiency, but is impractical due to needto manage peak pressures and due to high heat transfer.Spark-ignition engine:mixture of air (oxygen carrier) and fuelenters chamber during intake process.Mixture is compressed - combustion initiatedusing a high-energy electrical spark.Compression-ignition (Diesel) engine:air alone is drawn into chamber, compressed.Fuel injected directly into chamber near end ofcompression process.(Fuel used in compression-ignition engine must easilyspontaneously ignite when exposed to high temperature and pressure compressed air.)Diesel is often portrayed as having a slower combustion process(constant pressure instead of constant volume)Goal of rapid combustion near TDC for maximum efficiency is true for both Dieseland spark-ignition engines.14CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modeling8measuredpredicted7Pr essure, MPaZero-Dimensional ModelsHeywood, 1988measurep(q)V(q)Single zone model6543210-80-60-40-20020406080Crank A ngle, deg.dTdV j h j qComb q Loss q Netmcv p mdtdtj350q Net pwheredV1 dpV dt 1 dtq Loss hA(T Twall )Assume300Heat release rate (J/degree)Use the ideal gas equation to relate p & V to T250200150100500-50h and Twall-20-10010203040Crank ang le (deg ree)15CEFRC1 June 27, 20125060
Hour 1: IC Engine Review, 0, 1 and 3-D modeling3-Dimensional ModelsSolve conservation equations on (moving) numerical meshMassSpray source termsSpeciesMomentumcombustion source termsEnergyAmsden, 198916CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingTurbulence models (RANS - RNG k-e)Productionu i ’ Ui u iuiP ui u j S ijMean flow strain ratettk 3ui2/2l Ui tt k/eReynolds stresses turbulent/mean flow time scaleWang SAE 2012-01-014017CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingKIVA-3V CFD code: Flow solverMain program and approximately 50 subroutinesInitializationPhase ABig IterationPhase BPhase CRead input dataCalculate gas viscosityInitialize time step, piston velocitySpray modeling (injection, drop breakup, collision, evaporation )Combustion chemistryEmission modelingMass and energy contribution due to spray and combustionFluid phase calculationMass, momentum, velocity, temperature, pressure, turbulenceproperties (Implicit solver, iterations)Update droplet velocitySnapping/Rezoning gridsRemapping fluid properties to new gridsUpdate cell properties“Snapper”add/delete grid cellsAmsden, 199718CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modeling1-D Models1-D codes (e.g., GT-Power, AVL-Boost, Ricardo WAVE) predict wave action in manifoldsAt high engine speed valve overlap can improve engine breathing inertia of flowing gases can cause inflow even during compression stroke.Variable Valve Actuation (VVA) technologies, control valve timing to change effectivecompression ratio (early or late intake valve closure), or exhaust gas re-induction(re-breathing) to control in-cylinder temperatures.Residual gas left from the previous cycle affects engine combustion processesthrough its influence on charge mass, temperature and dilution.Lt L/c 1 m/330 m/s 3 msAVL Boost, Ricardo WAVE, GT-Power191 ca deg 0.1 ms @ 1800 rev/minCEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modeling1D ModelsReynolds Transport EquationdMgdd) system gd gd gVrel n dA csdtdt systemdt cvMass conservation:g 1 dMg / dt ) System 0dxDivergence theoremcv fixed ( A) 0 AV ) dxcv t 1.d AdxSupplementary: ( A) ( AV ) 0 t x4.StateMomentum conservation:2.P RT V V 1 P V 2 fV 2 / D 0 t x xEnergy conservation: e eP (VA) V q 2 fV 3 / D 3. t x A xAnderson, 1990205.e cvTf t w / V 2 / 2Q q Adx5 unknowns U: , V, e, P, and T5 equations for variation of flowvariables in space and timeNeed to evaluate derivatives / x, / tCEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingGas Exchange ProcesspinpexGasoline engine intake system:air filter, carburetor and throttle plate or port fuelinjector, intake manifold, intake port, intake valves.(in both gasoline and diesel engines).Intake and exhaust manifold designed tomaximize cylinder filling and scavenging.Intake system pressure drops (losses) occur dueto quasi-steady effects (e.g., flow resistance), andunsteady effects (e.g., wave action in runners).CylinderpressureblowdownCylinder Pressure, Valve LiftSupercharging – increases inducted air ntakeTDCoverlapBDCTDCEngine breathing affected by intake/exhaustvalve lifts and open areas (most of the losses).Valve overlap can cause exhaust gases to flow backinto intake system, or intake gases can enter theexhaust (depending on pin/ pex)Intake also generates large scale flow structuresthat can be used to promote turbulent mixing21Swirl and tumbleflowsCEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingIn 1-D models friction factors used to account for losses at area change or bendsby applying a friction factor to an “equivalent” length of straight pipeFlow lossesRApply experimentally ornumerically determinedLoss Coefficient toequivalent straight pipe P CP V 2 / 222CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingRicardo WAVE friction ware/Products/WAVE/23CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingVolumetric efficiencyAccurate descriptions of valveflow losses require considerationof multi-dimensional flowseparation phenomenaand their effect initial conditionsat intake valve closure (IVC).Highest mixing of incomingfresh charge and combustionproducts occurs whenintake flow velocities arelargest due to high flowturbulence (half-way throughstroke).CFD flow velocity and residual gas distributionduring gas exchange in plane of valves(intake valves about to close144 degrees ATDC - 1600 rev/min)24CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingRicardo WAVE valve model25CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingModel Optimization: Volumetric Efficiencyhttp://www.gtisoft.com/26CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingOptimization: Volumetric EfficiencyDelphi Cam ain/gas/valvetrain/vcp/27CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingOptimization: Volumetric Efficiency28CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingOptimization: Volumetric EfficiencyMercedes-Benz three stage resonance intake system29CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingVolumetric efficiency parameters (SI engine CI engine)A B C D E F GLosses inCarburetor,Intake manifoldheating (rho),Fuel vapordisplaces airMAP Pin Pexin dieselLower CR - SImore residualDiesel - moreresidual is airHeywood, Fig. 6.930CEFRC1 June 27, 2012
Hour 1: IC Engine Review, 0, 1 and 3-D modelingSummaryTransportation uses 1/3 of the total energy use in the USInternal combustion engines can be among the most efficient power plants knownto man, but research is needed to improve them furtherThe industry faces significant challenges to meet emissions regulations, butgreat progress has been made in the last 20 years.Modeling tools are available to help quantify engine performance and to providedirections for improved efficiencyUS HD emissions regulationsOil Consumption, 2010:USTotal Europe & EurasiaChina3121.1%22.9%10.6%Charmley, SAE 2004-01-2708CEFRC1 June 27, 2012
Engine fundamentals and performance metrics, computer modeling supported . So, CO 2 mass from engines/year added to earth’s atmosphere . Internal Combustion Engine development Requires control to: introduce fuel and oxygen, initiate and control combustion, exhaust products Heat source Heat sink
Generator Cooling System 4630 Liquid cooling system Internal Combustion/Reciprocating Engines Generator Cooling System 4640 Seal oil system and seals Internal Combustion/Reciprocating Engines Generator Cooling System 4650 Other cooling system problems Notes: 1) For use with Unit Codes 400-499.
CO5 Learn about the advanced technologies and research areas in engines. List of Experiment (ME417 Internal Combustion Engines) Sr. No. Title Course Outcomes 1 Comparison of S.I and C.I Engines CO1 2 Combustion Chambers CO3 3 Types of Carburetor CO1 4 Ignition System
Engines regulated by 40 CFR Part 86 typically include engines used in on-highway applications such as heavy-duty gasoline fueled engines (HDGEs), heavy-duty diesel fueled engines (HDDEs), and heavy-duty engines using alternate fuels (CNG, LPG and LNG). Engines regulated by 40 CFR Part 89 include compression-ignition engines used in nonroad .
The challenge with using a pile foundation for a reciprocating compressor package is that high dynamic forces and moments generated by the normal reciprocating compressor operation must be controlled. Controlling the d ynamic response requires understanding the dynamic properties of the piles and soil as well as the reciprocating compressor .
reciprocating compressor in which the balancing of the compressor will be studied. 1.3 Objectives The project is set out to achieve a few objectives which are listed as follows: To identify the unbalanced forces of the reciprocating compressor. To model and simulate out the reciprocating compressor's dynamics.
protecting reciprocating compressors on the market today. While pipeline operations are pulling out their reciprocating compressors, this machine is still the workhorse of refineries, chemical plants, and oil production facilities. As a result a new generation of interest has developed in effective condition monitoring of reciprocating compressors.
1981 First leakage-free reciprocating compressor with pressure-tight crankcase 1982 First reciprocating compressor for H2S sour gas 1983 First reciprocating compressor for municipal utility natural gas storage 1984 Admission of our reciprocating compressors through Germanischen Lloyd and delivery of the first one for gassing oil tanker
BAB 6 LEMBAGA JASA KEUANGAN DALAM PEREKONOMIAN INDONESIA KOMPETENSI INTI 3. Memahami, menerapkan, menganalisis pengetahuan faktual, konseptual, prosedural berdasarkan rasa ingin tahunya tentang ilmu pengetahuan, teknologi, seni, budaya, dan humaniora dengan wawasan kemanusiaan, kebangsaan, bakat dan minatnya untuk memecahkan masalah kenegaraan, dan peradaban terkait penyebab fenomena dan .
