Investigation of the pVTt Gas Flow Standard with Active Thermal Compensation

Abstract

pVTt has been employed as the primary gas flow standard in many countries due to its unique advantages like high accuracy, simple structure, low maintenance, etc. However, its calibration efficiency is relatively low because of the long stabilization time of intake and outtake procedures. To reduce the stabilization time, a novel pVTt gas flow standard with active thermal compensation was proposed. Above all, structure and principle of the new pVTt standard device was introduced. Subsequently, the numerical simulation was performed to investigate the influence of thermal compensation. Finally, experiments were carried out, and results showed that the stabilization time after intake completion could be reduced from ten minutes to one minute,which means calibration efficiency was improved a great deal.