전산해석을 활용한 원전용 평균피토튜브의 고압유동 특성 연구

Abstract

The flow measuring system with averaging pitot tube used in nuclear power plant must be qualified but the limitation of the test facility leads to use the numerical analysis instead of the calibration experiment with high pressure flow. The multiplication of flow coefficient and expansion factor is calculated with the pressure drop and mass flow rate obtained from numerical analysis. Generally, the multiplication of flow coefficient and expansion factor of averaging pitot tube in water is assumed to be same to that in the air fluid. But there is no justification of that assumption. The coefficients, which were calculated from the numerical analysis, were almost same values within small error. Also, from the justification of averaging pitot tube, the multiplication of flow coefficient and expansion factor from numerical analysis can be used in the differential pressure transducer of averaging pitot tube and flow computer with which the flow rate value is modified in considering the difference of real condition to the base pressure and temperature, where the relation of flow and differential pressure was calibrated.