Study On The Calibration Of A Supercharged Gasoline Engine And The Characteristics Of Dissociated Methanol Gas Engine

Energy conservation,emission reduction,and low-carbon development have always been the goals pursued by experts in the industry and are an inevitable trend for the development of automotive engines.In recent years,rapid economic development and social progress have made automobiles a necessary means of transportation,but their fuel consumption and emissions have also brought about corresponding problems.To this end,the industry has adopted a variety of technical means,including engine booster technology,alternative fuel technology.In this regard,this paper uses a certain type of supercharged gasoline engine as the research object.Based on the bench test,the calibration of this machine and the characteristics of its blended dissociated methanol gas are studied.Firstly,a supercharged gasoline engine test bench was built to calibrate a 1.5T supercharged gasoline engine so that it can obtain the best power and fuel economy under the conditions that meet the current emission regulations and usage requirements.In addition,based on the engine bench calibration of basic data and performance data,the GT-Power simulation model of the gasoline engine built was calibrated,and the air intake coefficient,intake pressure,exhaust temperature,and reversed torsion torque obtained during the test were passed.The data was model-calibrated.Finally,based on the established calculation model,the fuel was changed to gasoline blended with methanol,and the performance changes of the boosted gasoline engine after burning mixed fuel were studied.Studies have shown that when the engine speed is the same and only the engine fuel is changed,the dynamic performance of the gasoline engine when it is completely replaced with methanol is better than that when the gasoline engine is completely fueled with methanol and the dissociated methanol gas is used as the fuel.Because the latent heat of vaporization of methanol is greater than the latent heat of vaporization of gasoline,the intake air temperature is decreased,the air intake density is increased,combustion in the cylinder is more fully performed,and the oxygen content of methanol also promotes the flame propagation speed in the cylinder;the methanol cracking rate is In 90%,increasing the blending ratio will reduce the dynamic performance of the booster gasoline engine.This is the reason that blending will improve in-cylinder combustion,but since the blended dissociated methanol gas is in the gaseous state,increasing the blending ratio will also reduce the air quality entering the cylinder.As a result,the higher the replacement ratio,the lower the power of the gasoline engine.