The operating instability of a dual compensation chamber loop heat pipe (DCC-LHP) including temperature hysteresis, reverse flow and temperature oscillation is described and explained in this paper. Test results indic...The operating instability of a dual compensation chamber loop heat pipe (DCC-LHP) including temperature hysteresis, reverse flow and temperature oscillation is described and explained in this paper. Test results indicate that the steady state operating temperature under the variable conductance mode is not the same during the power cycle tests with the same heat load, and it is lower during the power reduction cycle than that during the power increase cycle. Orientation has an effect on the heat load range when temperature hysteresis occurs, and the effect of power variation amplitude can be ignored. Reverse flow tends to occur in some of the startups at low heat loads, even if vapor existed in the vapor grooves initially, which is caused by a higher pressure inside the wick due to evaporation in the evaporator core or vapor penetration into it. Temperature oscillation tends to occur in some of the startups at low head loads or some steady-state operations at high heat loads. Especially when the compensation chamber with the bayonet through is above the evaporator, the incidence rate of temperature oscillation is high.展开更多
对汽包双室平衡容器水位温压补偿控制系统进行了探讨和研究,根据温压补偿模型,分析了P L C系统难以独立实现的原因以及查表法的缺陷,提出了P L C系统与上位机系统相结合的水位温压实时连续补偿的综合控制策略,提出并分析比较了三种体系...对汽包双室平衡容器水位温压补偿控制系统进行了探讨和研究,根据温压补偿模型,分析了P L C系统难以独立实现的原因以及查表法的缺陷,提出了P L C系统与上位机系统相结合的水位温压实时连续补偿的综合控制策略,提出并分析比较了三种体系结构及其实现原理和技术,工程应用结果表明该控制系统提高了水位控制的实时性、稳定性、准确性和安全性。展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 50676006)
文摘The operating instability of a dual compensation chamber loop heat pipe (DCC-LHP) including temperature hysteresis, reverse flow and temperature oscillation is described and explained in this paper. Test results indicate that the steady state operating temperature under the variable conductance mode is not the same during the power cycle tests with the same heat load, and it is lower during the power reduction cycle than that during the power increase cycle. Orientation has an effect on the heat load range when temperature hysteresis occurs, and the effect of power variation amplitude can be ignored. Reverse flow tends to occur in some of the startups at low heat loads, even if vapor existed in the vapor grooves initially, which is caused by a higher pressure inside the wick due to evaporation in the evaporator core or vapor penetration into it. Temperature oscillation tends to occur in some of the startups at low head loads or some steady-state operations at high heat loads. Especially when the compensation chamber with the bayonet through is above the evaporator, the incidence rate of temperature oscillation is high.
文摘对汽包双室平衡容器水位温压补偿控制系统进行了探讨和研究,根据温压补偿模型,分析了P L C系统难以独立实现的原因以及查表法的缺陷,提出了P L C系统与上位机系统相结合的水位温压实时连续补偿的综合控制策略,提出并分析比较了三种体系结构及其实现原理和技术,工程应用结果表明该控制系统提高了水位控制的实时性、稳定性、准确性和安全性。