Performance Simulation And Test Research Of Exhaust Gas Turbine Power Generation System For Gasoline Engine

From the angle of heat balance of the internal combustion engine,the effective work of the engine is 30 percent to 40 percent of the total heat of fuel combustion in ideal condition.While most of the other is rejected in exhaust gas and cooling water,and heat removed by exhaust gas of total calories about 30 percent.The automotive industry is facing the dual challenges of energy saving and environmental protection.Energy saving and emission reduction have become the important goals of product development at home and abroad.The exhaust gas energy recovery and utilization by exhaust gas turbine power generation technology is one of the effective ways to improve vehicle efficiency and achieve energy saving and emission reduction.In this paper,the thermodynamic simulation model of the gasoline engine exhaust gas turbine generator system is established by using GT-POWER software,which is the research object of the G4 ED vehicle gasoline engine which is 1.599 L.The parameters such as fuel consumption,exhaust gas temperature and power generation are obtained.At the same time,the exhaust gas components of the gasoline engine are analyzed,and the calculation formulas of exhaust gas constant,constant pressure ratio heat capacity,constant volume ratio heat capacity and specific heat ratio exhaust state parameters are derived,and corresponding values are obtained.Then the variation law of exhaust gas state parameters,exhaust gas residual kinetic energy,exhaust gas residual pressure energy and exhaust gas residual heat energy under different working conditions is obtained,and the influence of exhaust gas state parameters on three forms of exhaust gas energy and exhaust gas turbine output power is studied.The simulation results show that the increase of engine speed and load,the exhaust gas state parameters and the three kinds of exhaust gas energy are increase.On the whole,the recovery potential of exhaust gas energy is large,the maximum value of 81.8461 kW.The exhaust gas residual heat energy is 65.5847 kW.The exhaust gas residual pressure energy is 15.7798 kW.And the exhaust gas residual kinetic energy is 0.4816 kW.The exhaust gas residual heat energy is the main object of the exhaust gas energy recovery compared to the three kinds of exhaust energy.Generally,the exhaust residual pressure can be recovered in high speed and high load areas,while the exhaust residual kinetic energy is negligible.In addition,the exhaust gas state parameters affect the three kinds of exhaust gas energy,the exhaust gas temperature has the greatest impact on the exhaust gas residual heat energy,the exhaust gas pressure has the greatest impact on the exhaust gas residual pressure energy,and the exhaust gas velocity has the greatest impact on the exhaust gas residual kinetic energy.The output power of the exhaust gas turbine is also increased with the increase of engine speed and load,the maximum output power is 32.6052 kW.The test results show that with the four exhaust gas state parameters have influence on turbine output power,and the exhaust gas temperature has the greatest influence on output power,and other parameters have relatively small impact.Compared to the turbine output power and the total exhaust gas energy,the exhaust turbine only recovered the 38.8708%~58.4341% exhaust gas energy,and the rest of the energy was released to the atmosphere in the form of exhaust gas.A test bench for exhaust gas turbine power generation system of gasoline engine was set up and related experiments were carried out.Two test items were identified: gasoline engine load characteristics test without exhaust turbine generator and load characteristic test of gasoline engine with exhaust gas turbine generator.The fuel consumption and economic comparison under two kinds of test projects are obtained.In addition,the test results are compared with the simulation results.The results show that the test results are in good agreement with the simulation results,but the simulation results are slightly higher than the experimental results,and the causes of the results are analyzed.Compared with the gasoline engine without exhaust gas turbine,the thermal efficiency of the exhaust gas turbine energy recovery test system of the gasoline engine increased by 15.20%,and the economy of the engine with exhaust gas turbine did not deteriorate significantly.So the exhaust gas turbine power generation system has a certain practical feasibility.