Development of a General Method for Determining Leak Rates from Limiting Enclosures

This paper discusses the development of a general method for the determination of very low leak rates from limiting enclosures. There are many methods that can be used to detect and repair leaks from enclosures. Many methods have also been proposed that allow the estimation of actual leak rates, usually expressed as enclosure volume turnover. The proposed method combines measurements of the state variables (pressure, temperature, and volume) as well as the change in the concentration of a tracer gas to estimate the leak rate. The method was applied to the containment enclosure of the Engineering Development Unit of the CELSS Test Facility, currently undergoing testing at the NASA Ames Research Center.