Abstract:

To make the high pressure(HP) stage compressor and the low pressure(LP) match with optimization and improve the efficiency of the whole two-stage turbo-charging system, the performance of a HP stage compressor was studied on a two-stage turbo-charging system test bench. In the turbo-charging system, the fresh air was first precompressed through the LP stage compressor to get the HP stage compressor′s inlet condition with high pressure ＆ high temperature. An intercooler was set between the HP and LP stage compressors. To each test curve had the same rotation speed, and the inlet temperature of the HP stage compressor was kept unchanged. The test results showed that there was much difference between the corrected speed and actual speed of the HP stage compressor only because the increase of its inlet temperature. In order to get the preconcerted pressure ratio, the speed of the HP stage compressor should be much improved. The corrected air mass flow of HP stage compressor was much less than its measured air mass flow, which was mainly because the great increase of inlet pressure of the HP stage compressor. In order to avoid a surge of the HP stage compressor, its inlet pressure should be controlled.

Key words:  two-stage turbocharging system, high pressure stage compressor, compressor performance