Patent ID: 6571767
Filing Date: 2003-06-03
Classification: F02D,G01F

Abstract:
A flow amount calculation controller for calculating a flow amount of fluid passing through a variable throttle portion provided in an air passage so as to control a certain subject comprising:a calculator that calculates a flow amount mt of the fluid passing through said variable throttle portion by the following formula: mt=AdÂ·(PuÂ·&rgr;u)Â½Â·((((kâˆ’1)/(2Â·k))Â·(1âˆ’Pd/Pu)+Pd/Pu)Â·(1âˆ’Pd/Pu))Â½where Pu is an upstream pressure of said variable throttle portion, &rgr;u is an upstream density of said variable throttle portion, Pd is a downstream pressure of said variable throttle portion, Ad is an opening area of said variable throttle portion, and k is a specific heat ratio of said fluid.