Closure to “Discussion of ‘Experimental and Theoretical Study of Surge in a Small Centrifugal Compressor’” (1981, ASME J. Fluids Eng., 103, p. 395)

Abstract

discrepancies between model and data appearing particularly near and after times of flow reversal (see m c (t) in Figs. 2(a) and 3(a), may be explained by the incompressibility assumption in the momentum balance for the compressor ducting, equation (la). Here, sample calculations have shown that the ignored terms involving the time-rate-of-change of mass in the ducting may amount to as much as 25 percent of the terms retained. The fact that the time periods, during which the ignored terms are significant, are short, however, may explain why the model results are still useful.