Research On The Feasibility Of Automobile Exhaust Heat-driven Stirling Engine

With the development of automotive industry, the global energy shortage is growing.So how to use exhaust heat energy of cars is increasingly attract researchers. As theenergy-saving devices, Stirling engine has some advantages, such as a wide range of fuels,high conversion efficiency, low noise and so on. Most scholars at home and abroad carriedout the research on the recovery of automobile exhaust energy, but the application of theStirling engine has ineffable significance in solving the energy shortage, improve energyutilization on recovering automobile exhaust energy. This article studies the automobileexhaust energy,the design of the Stirling engine heat exchanger system,try to identify themain factors to impact the efficiency of the Stirling engine through the performance oflaboratory tests,theoretical analysis and numerical simulation model, the Stirling engine isoptimized to provide the theoretical basis.In this paper, emphasizes automobile exhaust energy, which designed a Stirlingengine heat exchanger system to take advantage of automobile exhaust heat-drive. And onthat basis, provides the experimental performance test of a small-scale Stirling engine.Experimental studies include eight experiments which are the torque are constant andvariable, respectively, corresponding to the charge pressure of5bar,10bar,12bar and14bar.Test the heating temperature and charge pressure have an effect on output power of Stirlingengine. Make a analysis of engine dynamics energy. Numerical Simulation main contentsinclude using MATLAB software simulation Stirling engine working process (cyclicpressure17bar) and calculate the indicates power of engine at the different conditions(inflation pressure5bar,10bar,12bar,14bar). Use ANSYS software simulation the pressurefield of regenerator, and make a analysis of the impact of the regenerator pressure drop.Experimental studies indicate that:1, Heating temperature: the output power of engine increase along with heatingtemperature growth.2, Charge pressure: Different heating temperature, corresponding to different optimumcharge pressure. Before the best charge pressure, output power of engine increase alongwith charge pressure growth, after the best charge pressure, if continue to increase pressure,the output of engine will decline and vibration.3, During the cycle, the maximum total pressure close to7bar, which shows the flowresistance in the heat exchanger is relatively large, the size of the heat exchanger may beoptimized.4, The maximum torque of engine is5.39N.m which is obtained when the chargepressure of14bar, the speed of engine will reduce along with load growth. 5, The indicate and effective efficiency increase along with charge pressure growth.Numerical simulation studies indicate that:1, The indicated power of simulation and prototype have a large deviation, so the testengine need to be optimized prototype further.2, Because of the engine die volume and the flow resistance of regenerator, there is alarge deviation of the actual cycle and the ideal cycle of Stirling output power.3, The flow resistance loss of regenerator increase along with the wire mesh growthand the flow resistance loss of regenerator decline along with wire diameter of regenerator.In summary, in the Stirling engine design, the manufacture of high temperaturematerials should be selected heater; Also, make sure the loop pressure parameters, shouldfocus on the sealing performance of the working fluid. Actual and Ideal Cycle Stirlingengine cycle has a big difference, and is dominated by the presence of the regeneratorcaused, regenerator performance is a key factor affecting the merits of the Stirling engineperformance is good or bad.