EFFECT OF TIP CLEARANCE ON PERFORMANCE OF A CENTRIFUGAL COMPRESSOR

Abstract

The centrifugal compressor is to study the effect of tip clearance on the performance characteristics and the wall static pressure for a different flow coefficient. The method of testing the compressor is run at a constant speed at 2000rpm. The tip clearance is varied by using spacers. The volume flow rate is varied with the help of throttling device to conduct the performance test. The performance characteristic of the centrifugal compressor showing the variation of discharge pressure with volume flow rate is plotted. Obtaining the performance characteristics showing the variation of discharge pressure with volume flow rate for different tip clearance, viz. =2.2%, 4%, 6.1% and 7.9%. Measurement of periodic pressure at various tip clearance viz. =2.2%, 4%, 6.1% and 7.9%. For each tip clearance pressure measured in radial location of impeller at 6 positions for different flow co efficient values. Five flow coefficients viz., ф =0.40, =0.34 (both above design flow), =0.28 (near design flow), =0.21=0.18 (both below design flow) and four values of non-dimensional tip clearance viz., =2.2%, 4%, 6.1% and 7.9%, are chosen for experimental work. The objective of the research work is to measure the periodic variation static pressure on the casing over the rotor at different values of tip clearance and flow coefficients. With the availability of these data, it is possible to improve the tip clearance flow in centrifugal compressor.