The Analysis of Flow Separation Loss of Impeller in Centrifugal Compressor under Variable Conditions

摘要

In order to study the change condition of the influence on the centrifugal compressor blade field, we change the size of the centrifugal compressor inlet flow and the centrifugal compressor impeller rotational speed, using the realizable κ - ε ii equation model to do the steady numerical simulation for the full port of centrifugal compressor. Through calculation, we get different inlet flow and rotate speed of centrifugal compressor internal flow field distribution of relative velocity, at the same time using the concept of Degree of Separation Loss to analyze the separation loss within impeller passage. The results show that under the condition of variable working condition, the change of Angle of attack is the primary factor for the the impeller separation, and when the Angle of attack of the same time, the smaller the relative velocity, the greater the separation loss. Therefore in the process of actual production, in order to reduce the loss of separation, we should reduce the size of Angle of attack, appropriatly increase import flow or impeller rotational speed.