Design Of The Inlet Structure For Turbocharger Compressor Based On Numerical Simulation

Turbocharger used the waste gas that internal combustion engine produced to drive the compressor to compress the air, thus increased the amount of air into the internal combustion engine in unit time, provided enough air for fuel combustion, finally improved the efficiency of the internal combustion engine, and was widely studied. In order to deal with today’s complex working condition of engine, higher requirements of the turbocharger was presented. When turbocharger was working, the performance of the compressor eventually affected the performance of the turbocharger, and compressor’s structure and its parameter size determined the performance of the compressor. Therefore, the design and study of the compressor’s structure had a great role in promoting the promotion of the performance of the turbocharger. Because of the complexity of structure and flow field in compressor, proposed a compressor structure that can broaden the range of flow effectively and improve the maximum pressure ratio was a challenging.This subject designed and studied the turbocharger compressor inlet structure by using computational fluid dynamics. First, studied compressor’s performance by variable reflow slot width in inlet, secondly, studied the compressor’s performance by guide vanes in casing treatment based on the parameter optimization of inlet structure.When was setting up the calculation model of compressor, the reverse engineering design method was used to establish the turbocharger compressor geometry model that used in this subject firstly. Then meshed the compressor secondly, a meshing method that suited for turbocharger compressor’s flow field was purposed. In the numerical simulation of turbocharger compressor’s performance, the study of the reflow slot width of inlet structure showed that broadened the reflow slot width can delay the arrival of compressor’s surge limit and broaden the map width, the efficiency of compressor was slightly reduced at compressor’s test points when the slot width was increased, because of the more friction and mixing lost in casing. When designed and studied the casing structure of inlet, blade was set in casing structure, two different shape of blades was set in casing structure, studied the effect on the performance of the compressor with two kinds of vanes. The results showed that the vanes in caving can delay the arrival of compressor’s surge limit, broaden the map width, enhance the maximum pressure ratio, and the circular vane’s performance was superior to the straight vane.At last, by the research and design above, purposed a compressor’s inlet structure to improve the flow performance and maximum pressure ratio of compressor. When at 80000 rpm and 100000 rpm speed, the inlet structure can result in the following survey results:surge limit flow rate reduced by 27% and 11%, the flow width broadened by 30% and 30%, the maximum pressure ratio increased by 2.4% and 2.1%, respectively. After the designed and researched of the turbocharger compressor inlet structure, purposed a new type of inlet structure based on the original compressor inlet structure, effectively reduced the surge limit flow of the compressor, broadened the flow width, and enhanced maximum pressure ratio.