GAS FLOW CONTROL DEVICE FOR USE IN AEROSPACE THERMAL AND ATMOSPHERE CONTROL SYSTEMS
Abstract
The purpose of the work was to develop a small, lightweight oxygen flow control device able to deliver 2.65 + 0.05, -0.00 lb/hr oxygen at a nominal outlet pressure of 200 psig when supplied by an upstream pressure regulator and operated in ambient temperatures from -40F to +200F. The flow controller meters the oxygen through a variable area choked flow orifice. The orifice assembly consists of a rod, spring-loaded against a diaphragm and allowed to move axially inside a sharp edged hole. The variable orifice is formed by the gap between the edge of the hole and a flat machined on the periphery of the rod and inclined to the rod axis. Axial motion of the rod varies the gap, and therefore the orifice area. One side of the diaphragm is exposed to the upstream pressure of the orifice, and the opposite side is exposed to a trapped constant volume of gas having a pressure proportional to the gas temperature. The diaphragm deflection and the orifice area are linearly related to the pressure and temperature of the gas at the device inlet. Proper selection of the critical design values enables the variation of orifice area to compensate for changing inlet conditions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1970
- Accession Number
- AD0708160
Entities
People
- Andrew C. Harvey
- Clemens M. Meyer
- Seth R. Goldstein