FLUID ANALYSIS METHOD FOR ROTARY FIELD

PROBLEM TO BE SOLVED: To perform the numeric analysis of fluid flow in a space including a rotary part accurately and speedily by analyzing an area near the rotary part of an analysis space by the rotary coordinate system equation and analyzing the remaining part by a non-rotary coordinate system equation. SOLUTION: The analysis region of a radius OC is subjected to numerical analysis by dividing the region into three regions, namely a region V1 of the cylindrical part of a radius OA that is smaller than the inner diameter of an impeller 5, a region V2 that is surrounded by the cylindrical part with a radius OB that is larger than the outer diameter of the impeller 5, and a region V3 that is surrounded by the cylindrical part with a radius OC and the region V2 . Then, a rotary coordinate system is used in the region V2 including a rotary part, while a stationary coordinate system is used in the regions V1 and V3 . Since the region V2 including the rotary impeller 5 is calculated by using the rotary coordinate system, a calculation time can be reduced to approximately 1/100 as compared with that by the time advance method and at the same time non-compression Navier Stokes equation can be applied in the region V2 , so that the result of a numerical analysis has physical meaningful and is fully useful for analyzing an actual centrifugal blower.