利用加热单元和单元进水系数的概念，经过详细的理论分析和数学推导，提出了压水堆二回路各级抽汽的热功转换系数，利用该系数得出了压水堆二回路的热力系统经济性诊断的定量数学模型，并通过实例计算验证了本文所提出方法的准确性

The objective of this work is to analyze the performance of steam-driven jet injector for its design and application in the district-heating system. The paper experimentally studied the performance of a steam-driven jet injector with central steam nozzle configuration. Three injectors with throat diameters of 16 and 20mm were tested. The main inlet parameters tested-steam pressure, water pressure and water temperature-were in the range of 0.20-0.60MPa, 0.14-0.49MPa and 18-68C, respectively. Experimental results show that the pressures were almost constant for the steam-water two-phase flow in the variable section channel of the mixing chamber tested, whose values were mainly affected by inlet steam pressure, inlet water pressure and temperature, and a shockwave appeared at the outlet of the mixing chamber. The lifting-pressure coefficient and jet coefficient measured were 1.27-2.1 and 7.63-43.65, respectively. A simplified mathematical model has been developed to predict the performance of the injector based on conservation of mass, momentum and energy as well as the present experimental data. The predictions agreed with the experimental data within

A brass block was constructed as a test block to study the Marangoni condensation in this paper. The maximal temperature difference of the block surface on which pure steam condensed was 11℃ when the block was cooled by the normal temperature water. Regulations and modes of Marangoni condensation for mixture vapor with different mass fractions were studied when the speed of vapor was 0.3m/s. As both temperature gradients and concentration gradients exist on the condensing surface, the experimental results indicate that the maximal heat transfer coefficient of mixture vapor can be 2.8 times that of pure steam when the Marangoni condensation of mixture vapor appears. The heat transfer coefficient of mixture vapor increases with the decrease of surface subcooling, and it appears a steep increase when the surface subcooling is small enough; the heat transfer flux has a maximum value as the surface subcooling rises; and the different modes of condensation are confirmed when the different ethanol concentration and different surface subcooling exist.

本文针对超音速汽液两相流在变截面通道中的升压过程进行了实验研究，得到了变截面混合腔中超音速汽液两相流的压力变化规律，通过实验结果的分析得出了变截面混合腔中的渐缩部分的压力分布与出口压力无关、变截面通道的渐扩部分为一个单相流体扩压管、压力突变发生在变截面混合腔喉部和随着出口压力升高而激波强度增大、变截面超音速汽液两相流升压技术具有定流量特征等结论。

根据质量、动量、能量守恒方程建立了变截面通道内超音速汽液两相流升压装置的极限升压能力计算数学模型。计算及研究表明：极限升压能力随变截面混合腔喉部直径、被升压的低压水流量和蒸汽喷嘴压比增加而降低，随环形水喷嘴间隙的变化出现了最小值；计算得出变截面超音速汽液两相流装置的极限升压能力可达26；在设计升压装置时应尽可能选取较大的蒸汽喷嘴压比和较小的环形水喷嘴间隙。同时给出了变截面混合腔喉部直径的设计原则。研究结果对变截面通道内超音速汽液两相流升压技术的应用有重要意义。