Nozzle pitot averaging primary

Abstract

A nozzle pitot primary for effectively sensing and measuring differential or velocity pressure of a system of air or gas flowing within a duct or conduit. By determining differential or velocity pressure, it is appreciated that the air or gas flow can be readily determined. The nozzle pitot primary of the present invention comprises a nozzle designed to be installed within a duct or conduit with the nozzle including a constricting throat area relative to the duct or conduit in which the same is installed. Air or gas passing through the duct or conduit is directed through the nozzle so as to produce a generally uniform and predictable velocity profile within the nozzle downstream from the throat area therein. An array of static and total pressure pitots are provided in association with the nozzle and are spaced inwardly across a constricted area where the velocity profile is relatively uniform. Because of the relative uniform velocity profile about the area of the pitots, it follows that an accurate indication of fluid flow can be determined without the necessity of sensing differential pressure at multiple points across the nozzle's cross sectional area.