Patent ID: 6671657
Filing Date: 2003-12-30
Classification: F04D

Abstract:
A computer-implemented method of calculating various types of characteristic curves of a centrifugal fluid machine, wherein two prescribed characteristic curves Y1=a11+a12x+a13x2+ . . . +a1nx(nâˆ’1) and Y2=a21+a22x+a23x2+ . . . +a2nx(nâˆ’1) formed of high-order equations for a centrifugal fluid machine are used to calculate a characteristic curve Y3=b1+b2x+b3x2+ . . . +bnx(nâˆ’1) formed of a high-order equation which passes through different coordinates (x3, y3), said method characterized by comprising:selecting prescribed coordinates (x1, y1) on said characteristic curve Y1 and corresponding prescribed coordinates (x2, y2) on said characteristic curve Y2; and calculating and outputting a characteristic curve Y3=b1+b2x+b3x2+ . . . +bnx(nâˆ’1) formed of a high-order equation which passes through different coordinates (x3, y3), with use of an equation bn={a1nkh1(1/kq1)(nâˆ’1)Ã—(y3âˆ’y2)/(y1âˆ’y2)}+{a2nkh2(1/kq2)(nâˆ’1)Ã—(y1âˆ’y3)/(y1âˆ’y2)}, wherein kq1 is a ratio (=x3/x1) of the selected coordinate x1 and the different coordinate x3, kh1 is a ratio (=y3/y1) of the selected coordinate y1 and the different coordinate y3, kq2 is a ratio (=x3/x2) of the selected coordinate x2 and the different coordinate x3, and kh2 is a ratio (=y3/y2) of the selected coordinate y2 and the different coordinate y3.