CO_2水合物蓄冷系统性能的实验研究

Experimental Research on Performance of CO_2 Hydrate Cool Storage System

本文采用直接接触式CO2水合物蓄冷系统,在釜内初始水温26℃以及充注压力（3.5-4.0）MPa条件下,研究不同充注压力下的蓄冷特性.实验结果表明：在充注压力为3.5MPa时,两相CO2在反应釜的初始入口干度为0.88;系统蓄冷速率为2.38kW,釜内中下层温度突升明显;充注压力增至（3.6-4.0）Mpa时,两相CO2的初始入口干度依次降至0.78、0.64、0.51、0.40、0.35,蓄冷速率也依次增至3.28kW、3.73kW、4.82kW、5.94kW和6.40kW,釜内中下层温度分离;系统的蓄冷过程不断消耗CO2,两相CO2的入口干度不断增大,系统蓄冷速率减小;系统充注压力越高,蓄冷特性越好.

For the direct-contact CO2 hydrate cool storage system, the cool storage characteristics were analyzed under the initial water temperature of 26 ℃ and refrigerant charge pressure of （3.5- 4.2） MPa in the reaction kettle. The experimental results show that, under the charge pressure of 3.5 MPa, the inlet vapor quality of two-phase CO2 in the reaction kettle was 0.88; the cool storage rate was 2.38 kW, and the middle and lower temperature rose significantly. As the charge pressure increases up to （3.6 - 4.0） MPa, the inlet vapor quality of CO2 is decreased to 0.78, 0.64, 0.51, 0.40 and 0.35, and the cool storage rate is increased to 3.28 kW, 3.73 kW, 4.82 kW, 5.94 kW and 6.40 kW, respectively, which leads to a temperature separation phenomenon between middle and lower part in the kettle. As the cool storage process consumes CO2 constantly, the inlet vapor quality of CO2 increases and the cool storage rate decreases. The cool storage performance can be improved greatly as the charge pressure increases.