Unsteady flow generator for gases using an isothermal chamber

Abstract We propose a chamber called an ‘isothermal chamber’ that can produce almost isothermal conditions due to its large heat transfer area obtained by filling it with steel wool. Using this chamber, a simple method to measure flow rates of ideal gases has been developed. In this paper, we propose an unsteady flow generator for gases using the isothermal chamber that can be useful for measuring the dynamic characteristics of gaseous flow meters. The mass flow rate is generated by controlling the pressure change during air discharge in the isothermal chamber using a servo valve. Steady and unsteady oscillatory flow is generated with the generator, and the effectiveness of the generator is demonstrated.