Unsteady Flow Rate Measurement of Air Using Isothermal Chamber

Kenji KAWASHIMA, Toshinori FUJITA, Toshiharu KAGAWA
1997 Transactions of the Society of Instrument and Control Engineers  
It is difficult to measure the flow rate of compressible fluids, because the volume of compressible fluids changes with temperature. Therefore, there is no easy and effective method on the unsteady flow rate measurement of compressible fluids. We have proposed a simple method to measure instantaneous flow rates of air using an isothermal chamber. In this paper, a simple method to measure the unsteady oscillating flow rate of air using the chamber is proposed. The isothermal chamber can almost
more » ... alize isothermal condition due to larger heat transfer area by stuffing steel wool in it. Therefore, the flow rate of air discharged from the chamber is obtained only by measuring pressure in the chamber. The unsteady oscillating flow rate is generated by a servo valve installed on the chamber. At first, the measurement error of the method is examined. Then, the unsteady oscillating flow rate was measured by the proposed method against several frequencies. It became clear from the experiment that the proposed method can measure the unsteady oscillating flow rate upto 40[Hz] within 7% of errors.
doi:10.9746/sicetr1965.33.149 fatcat:omaypmgmlbgnljt3bcpmlsn5ny