封闭式喷雾冷却系统启动时间

以蒸馏水为冷却工质，对冷凝器内置的封闭式光滑表面喷雾冷却系统进行了启动时间变化规律的实验研究,结果表明喷雾系统不同模块最优启动顺序为冷凝器、泵和加热器。采取6种不同的启动顺序，启动后加热表面的温度不均匀度均小于0.25 ℃。在最优启动顺序下，研究了冷却水流量、泵高度、加热功率和喷雾流量对启动时间的影响。随冷却水流量和喷雾流量增加启动时间缩短，随泵高度增加启动时间略微增大，随加热功率增大启动时间先增大后减小。启动时间影响程度由大到小的因素依次为喷雾流量、冷却水流量、加热功率及泵相对于加热表面的高度。喷雾工质流量由10 mL/min增大到35 mL/min时，封闭式喷雾系统的启动时间缩短了5 000 s。同样操作条件下,封闭式系统的启动时间比开放式系统延长15%~20%。

Startup time of closed loop spray cooling system

Using water as coolant, a closed loop spray cooling system with a built in condenser is established and the variation of startup time is measured dynamically. The optimized startup sequence for different modules is condenser, pump and heater. Under the optimized startup sequence, experimental investigation of the effect of operation parameters, such as cooling water flow rate, heating power, pump height and spray flow rate, on startup characteristics is made. The startup time decreases with the increase of the cooling water flow rate and spray flow rate. The descending order of influence of the factors is as follows: spray flow rate, cooling water flow rate, heating power, and relative height of pump. The startup time reduces by about 5 000 s when the spray flow rate increases from 10 mL/