An automatic stepping measurement system with highfrequency response was designed, whose probe can measure the flow field of compressor at any position in the inlet section .The measuring device was then used to measure the flow field distribution of inlet section of the centrifugal compressor with the help of onedimensional hot wire anemometer probe. All 54 measuring points were distributed uniformly at an interval of 9 mm in the inlet section of compressor with 9 points in the radial direction and the measurement was conducted every 30° along the circumferential direction in a cycle until the whole velocity distribution was acquired. The operating conditions of compressor included 40 000 r/min nearchoked steady state point, highest efficiency point and nearchoked point of 20 Hz pulsating back pressure. It was found that the pressure ratioflow curve of centrifugal compressor exhibited a hysteresis loop around the steadystate characteristic under the pulsating back pressure. Under steady conditions, the inlet flow field had a significant distortion and the velocity distribution exhibited an obvious circumferential asymmetry with a highspeed zone within a circumferential angle between 180° and 360°. In addition, the inlet flow field showed a strong unsteady characteristic under the pulsating back pressure condition. There was a circumferential asymmetry, which became important in the emptying section and weakened in the full section.
ZHANG Kaiyue
,
YANG Mingyang
,
SHU Mengying
,
DENG Kangyao
. Measurement of Inlet Flow Field of Centrifugal Compressor under Pulsating Conditions[J]. Vehicle Engine, 2020
, 0(3)
: 7
-11
.
DOI: 10.3969/j.issn.1001-2222.2020.03.002