ターボポンプの気液二相流性能に及ぼす液中溶存空気量の影響

抄録

In the present study, the gas-liquid two-phase flow performance of a turbopump equipped with an inducer was experimentally investigated. The almost homogeneous bubbly two-phase flow condition was successively set by the uniform aeration of gas dissolved in water upstream of the test pump, which was realized by a sudden pressure decrease with the valve closure. The gas-liquid volumetric flow rate ratio was estimated from the pump inlet pressure and the initial amount of dissolved oxygen under the assumption of mass equilibrium condition of the local dissolved oxygen. The effect of dissolved oxygen content on the gas-liquid two-phase flow performance of a turbopump was investigated. The results showed that low DO conditions are not suitable for evaluating gas-liquid two-phase flow performance because of in-negligible effect of vaporous cavitation. In addition, the effects of a reduced-diameter suction pipe and a swirl brake on the gas-liquid two-phase flow performance of a turbopump were investigated. The results showed that the effect on the gas-liquid two-phase flow performance was small under high DO condition, but the performance deteriorated under low DO condition.