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41.
搭建了以泡沫铜翅片换热器为核心的烟气水分回收实验台,研究了冷却水进口温度、烟气雷诺数及烟气中水蒸气体积分数对该换热器水回收特性和换热特性的影响,基于实验数据,利用多元回归拟合得到对流换热的关联式,其预测值与实验值误差在6%以内。结果表明:水蒸气体积分数增大可以显著提升水回收特性,而冷却水进口温度及烟气雷诺数对其影响很小;冷却水进口温度与烟气雷诺数对换热效率的影响较大,冷却水进口温度与换热效率成反比,烟气雷诺数与之成正比,而水蒸气体积分数对其影响较小;实验获得的最大冷凝水产率为7.68 kg/h,最大冷凝率为56.94%,最大换热效率为96.95%。 相似文献
42.
Using nanoporous ceramic composite membranes to remove sulphur dioxide and to recover water vapor in flue gas is a new method, and this paper studied the effects of sulphur dioxide on the water recovery process. In this study, the outer‐side coating of hollow nanoporous ceramic composite membrane is selected as the study object. In the membrane module for desulphurization, one end of membrane is closed to create the high‐pressure environment inside membrane to ensure that the cooling water in the membrane penetrates the outer surface of the membrane to form a stable water film which can absorb sulphur dioxide from flue gas. In the membrane module for recovering water, using a vacuum pump to create micro‐negative pressure environment inside membrane, and then water vapor and condensate can penetrate through the membrane under pressure difference. Based on the ceramic composite membrane module, an integrated experimental platform for desulphurization and water recovery is constructed, and the mathematical model for predicting water recovery performance is established. According to the experimental and theoretical results, the mathematical model can predict the water recovery performance of the ceramic composite membrane. 相似文献
43.
为合理把握防水透气膜的防水和透气性能,从结露现象的本质入手分析了防水透气膜在应对建筑结露问题的作用机制,并从试验测试和生产工艺的角度提出了防水透气膜的性能控制要点。 相似文献
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MQ silicone resins, which represent a broad range of hydrolytic condensation products of monofunctional silane (M) and tetrafunctional silane (Q), were synthesized by reaction of water glass with hexamethyldisiloxane. The optimum reaction time and the optimal reaction temperature is 30 min and 30–40°C, respectively. Concentrated hydrochloric acid is the best one among those catalysts tested. In large-scale experiments (420–1680 mL), the favorable feeding order is catalyst first, and then water glass, the mixture of hexamethyldisiloxane and ethanol last and most MQ silicone resin was observed. The structure of MQ silicone resin was characterized by FT-IR and GPC spectra. The MQ silicone resin shows narrow molecular weight distribution and the number average molecular weight of MQ silicone resin is 2917. The silicone pressure sensitive adhesive prepared from as-synthesized MQ resin has good tack (29#) and 180° peel adhesion (5.630N/20 mm). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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《Journal of Nuclear Science and Technology》2013,50(4):159-163
To present a simple method for calculating the worth of control rods in multiregion reactor cores, the well model approximation is applied to the finite difference diffusion code. The results of calculation are compared with experimental results obtained on the ōzenji Critical Facility, and also with calculations using transport equivalent constants. With its simplicity, the method proposed is accurate enough to suffice amply for most cases where only the reactivity is the end result sought, although the application of this method is limited to control rods inserted in the core region, and gives no information about the detailed neutron flux distribution around the control rod. 相似文献
48.
由2,5-二氨基苯磺酸和四氯苯醌一缩合制得缩合物2,5-双(4-氨基-3-磺酸基苯胺)-3,6-二氯苯醌(A);该缩合物在15%发烟硫酸和过氧二硫酸铵作用下,发生分子内环合制得3,10-二氨基-6,13-二氯三苯二恶嗪-4,11-二磺酸(B);在氧化剂过氧化苯甲酰的作用下,B与苯亚磺酸钠二缩合得到三苯二恶嗪型酸性蓝AXG。本文对一缩合反应、环合反应、二缩合反应的物料配比、反应温度、反应时间等因素进行了探讨,找出了较佳反应条件。 相似文献
49.
Jens L. Eftang Anthony T. Patera 《International journal for numerical methods in engineering》2013,96(5):269-302
We introduce a port (interface) approximation and a posteriori error bound framework for a general component‐based static condensation method in the context of parameter‐dependent linear elliptic partial differential equations. The key ingredients are as follows: (i) efficient empirical port approximation spaces—the dimensions of these spaces may be chosen small to reduce the computational cost associated with formation and solution of the static condensation system; and (ii) a computationally tractable a posteriori error bound realized through a non‐conforming approximation and associated conditioner—the error in the global system approximation, or in a scalar output quantity, may be bounded relatively sharply with respect to the underlying finite element discretization. Our approximation and a posteriori error bound framework is of particular computational relevance for the static condensation reduced basis element (SCRBE) method. We provide several numerical examples within the SCRBE context, which serve to demonstrate the convergence rate of our port approximation procedure as well as the efficacy of our port reduction error bounds. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
50.
Film condensation is a vital phenomenon in the nuclear engineering applications,such as the gas-steam pressurizer design,and heat removing on containment in the case of postulated accident.Reynolds number in film condensation can be calculated from either the mass relation or the energy relation,but few researches have distinguished the difference between them at present.This paper studies the effect of Reynolds correlation in the natural convection film condensation on the outer tube.The general forms of the heat transfer coefficient correlation of film condensation are developed in different flow regimes.By simultaneously solving a set of the heat transfer coefficient correlations with Remass and Reenergy,the general expressions for Remass and Reenergy and the relation between the corresponding heat transfer coefficients are obtained.In the laminar and wavefree flow regime,Remass and Reenergy are equivalent,while in the laminar and wavy flow regime,Remass is much smaller than Reenergy,and the deviation of the corresponding average heat transfer coefficients is about 30% at the maximum.In the turbulent flow regime,the relation of Remass and Reenergy is greatly influenced by Prandtl number.The relative deviation of their average heat transfer coefficients is the nonlinear function of Reynolds number and Prandtl number.Compared with experimental results,the heat transfer coefficient calculated from Reenergy is more accurate. 相似文献