Investigating the Effects of High Reactivity Fuel with Gasoline-Bioethanol Blends on Reactivity Controlled Compression Ignition (RCCI) Engine

Abstract

The Diesel Engine Is The Main Prime Mover Widely Used For Land Transportation And Power Generation Applications On Account Of Higher Thermal Efficiency. Research On Better Combustion Technologies And Renewable And Clean Energy Sources Is Being Driven By Environmental Contamination As Well As The Current Energy Crisis With A Special Emphasis On Reducing Pollutant Emissions From Internal Combustion Engines. Developing Advanced Control Strategies Is A Significant Research Gap In Rcci Engines. Optimal Control Strategies Need To Be Developed To Achieve Stable Engine Operation. Combustion Rate Control Deficiency At Higher Engine Loads Is Due To Higher Self-Ignition Features Of The Direct-Injected Diesel Fuel. This Includes Addressing Issues Related To Combustion Phasing Control Without Using Egr Which Has A Negative Impact On Increasing Soot Emission And Reducing Power Output. In This Study, An Experimental Investigation On A Triple-Fuel Reactivity Control Compression Ignition (Rcci) Engine Running On Port-Injected Gasoline-Ethanol Blend And Direct-Injected Diesel Fuel Was Conducted. The Intake System Was Modified To Use Port Fuel Injection In Rcci Operations For Controlling Emissions, In-Cylinder Charge Reactivity, And Combustion Phasing. Taguchi Method Experimental Design Optimization Was Employed To Assess The Impact Of Various Independent Variables Utilizing Three Set Levels And Two Factors With The L9Orthogonal Array. The Combustion Simulation Was Carried Out To Analyze The Effect Of Four Different Piston Bowl Shapes (P1, P2, P3, And P4) And Was Successfully Validated. The Simulation Model Shows That The Peak Cylinder Pressure (Pcp) Of P2 Is 131 Bar And The Pcp Of P4 Is 113 Bar. The Combustion Temperature Was Found To Be Maximum At 2048.2k For P2, And The Lowest For P4 At 1680.9k While The Same For P2 Was 18% Higher Than That Of P4. The Peak Heat Release Rate (Hrr) For P3 Was Determined To Be 0.082 J/Ca With A Great Variation Between Maximum And Minimum Due To The Presence Of Pre-And Post-Injection, And The Hrr For P4 Was 0.035 J/Ca With The Single Injection. The Hrr Was The Highest ForP3 And P4 Was Lower By 39%. The Nox Emissions For P1, P2, P3, And P4 Were Found To Be 25.62, 16,18.2, And 12.74 G/Kwh Respectively. The Lower Nox For P2 Was Due To A Lower Fuel Fraction Of Near-Wall Flow Dilution On The Outer Portion Of The Sleeve, Low Fuel Fraction In The Core Region Of The Free Spray, In The Front Portion Of The Free Spray, And The Core Of The Fuel-Free Spray. The Experimental Investigation OnG25e75-Rcci Operation Showed A Pcp Of 91 Bars At 3000 Rpm And A Minimum Of 58 Bars At 2600 Rpm With Baseline As Diesel (D100g0e0) Alone. The Peak Hrr Is 62 J/Ca At 3000 Rpm When Operating With The G25e75-Rcci Engine And A Minimum Of 12 J/Ca For G50e50-Rcci Operation. The Engine Operating With G25e75 Pre-Mixed Fuel Had A Minimum Nox And Co2 Emission. The Brake Power Is Maximum At3000 Rpm, And The Brake Torque Is Maximum At 2400 And 2500 Rpm With The Engine Running On AG50e50-Rcci Engine. Varying The Amount Of Hydrous Bioethanol In The Port Injected Premixed Fuel, The Engine Performance And Emissions Were Observed To Be Greatly Affected. Taguchi Optimization Results Showed That Speed (Delta 10.75, Rank = 1) Has The Largest Effect On The Signal-To-Noise Ratio (Snr), And Delta 38.96, Rank = 1, Has The Largest Effect On The Response Of Means At 3000 Rpm. The Fuel G25e75(Delta 87.30, Rank 1) Has The Largest Effect On The Standard Deviations (Std). The Strongest Means In Engine Speed And Premixed Fuel Were Nox, Co, Hc, And Brake Power. At 3000 Rpm, The Speed Had The Larger Main Effect Plots Of Snr. The G25be75 Operating Mode Had The Strongest Main Effect Plots For Means And Std. High Engine Speeds And Higher Ethanol Content In The Rcci Premixed Fuel Are Preferred For Reducing Nox And Co2, While Hydrocarbon (Hc) And Co Showed A Slightly Increasing Trend Even Though Observed To Be Lower Than That Of Diesel In The Lower Speed Range. The Brake Thermal Efficiency While Being Lower With Rcci At Lower Speeds, Is Almost On Par With Conventional Diesel At High-Speed Range, With The Present Blends Tested, Higher Speeds Seem To Be Preferable From A Performance Perspective While The Best Emission Performance Has Been Observed At Intermediate Speed.