The Design And Key Technology Research Of Two-stage Turbocharger For V12 Engine

Two stage turbocharging technology can improve the performance of engine preferably. this paper, therefore, adopts a two stage turbocharging system with an intercooler to a V12 cylinder diesel engine. For two methods of designing high pressure stage turbines, study how two methods influence the performance of two turbines by using the method of numerical simulation and computation.Using the maximum torque point of 1800r/min as the design operating point and the operating point of 2500r/min as the reference operating point, the turbocharger parameters are carried out based on the V12 diesel engine cylinder design parameters. Then the JP95 compressor is chosen as the high-pressure stage compressor and the J140 compressor as the low-pressure stage compressor. The MAPs of performance of two turbines are created by the method of the original turbine data multiplied by correlation coefficient.V12 diesel engine model is established by the WAVE software. On account of the result of simulation, the angle of vale under different speed of full load is decided. The results of calculation show that the two stage turbocharging system can satisfy the requirement of the engine design, and have good performance.In this paper, two schemes of designing high pressure turbine are studied. By analyzing the internal flow of the two turbines, study the influence of different design method on the turbine performance. The original method is that the appropriate performance of the turbine is obtained by changing A/R value of the 0-0 section of volute under keeping the same impeller. The new method is that the new turbine is designed based on the load coefficient and flow coefficient under the same situation as the original one. The result of simulation show that due to the incidence angel is more close to the optimal angle, the clearance loss and flow loss of suction side of the impeller is small and the efficiency of turbine is improved.