Abstract: Based on the principle of compressor surge and choke, a model for the adjustable inlet equipment on a compressor is built up using CAD. The model is then meshed, and the velocity distribution of the outflow field obtained using CFD. The result is compared to the ideal velocity distribution, and the model is adjusted, calculations improved to attain best results. On this basis, a protomodel is made and experiments has been done with it. From the experimental, results it is observed that the adjustable inlet equipment can efficiently put off the occurrance of compressor surge and choke, and a wider range of flow in compressor working can be achieved.