METHOD OF DESIGNING MINUTE FLOW RATE CONTROLLER WITH ENTRANCE THROTTLE GROOVE

摘要

A method of designing a minute flow rate controller that is capable of accurately controlling the minute flow rate of a fluid and realizing desired valve characteristics without inducing any unsteadiness of fluid flow and has a simple configuration with respect to a throttle groove for controlling the fluid flow rate. With respect to a minute flow rate controller comprising inflow passage (12) for introducing a fluid, valve member (2) furnished with main throttle groove (6) for causing the introduced fluid to flow from a starting end toward a finishing end thereof, fluid outflow port (20) opened with an optional cross section by a flow rate regulating member and outflow passage (14) for leading out the fluid flowing out from the fluid outflow port (20), there is provided a method of designing the minute flow rate controller with entrance throttle groove, comprising providing entrance throttle groove (8) communicably preceding the starting end position of the main throttle groove (6), and, on the basis of a relational expression derived from the momentum equation of the fluid flowing through the entrance throttle groove (8) and the main throttle groove (6), determining the size of the entrance throttle groove (8) so as to exhibit a desired flow resistance.