基于ANSYS分析内融冰蓄冰槽的蓄冰模型

对内融冰的蓄冰槽蓄冰的相变传热提出了简化假设，并在此基础上用ANSYS有限元分析软件对其建立模型。改变蓄冷槽换热管的排序、管间距及不同的初始温度情况下，分析了蓄冷槽结构和工况对蓄冰性能的影响。     

盘管式蓄冰槽传热性能研究综述

蓄冰槽作为冰蓄冷系统的核心部件,一直是学者们研究的重点之一。本文以常用的盘管式蓄冰槽为例,通过查阅国内外文献,总结蓄冰和融冰的理论模型与影响因素,分析蓄冰和融冰过程传热性能的研究方法。     

有限空间内水平顺排管束外蓄冰过程特性的实验研究

管束排列是静态管壳式蓄冰槽所采用的基本方式,实现管排布置的合理性是进行此类装置设计的一般要求,了解管束布置下的管外蓄冰过程特性对于进行优化设计具有重要的帮助。采用在有限空间内水平顺排布置九根蓄冰管,以中间管为主要研究对象,通过实现恒壁温条件,实验研究了管外冰层发展的特性,以及管间的相互影响。结果表明,当试验段初始水温度较高时,受诱发自然对流影响,中间管外的结冰开始时刻要滞后其它管;与单管情况相比,管束外冰层轮廓的发展受自然对流的影响要小的多。中间管外的冰层发展要优于上下管。在各管均在蓄冷开始后就结冰的情况下,设定的无因次温度可以作为衡量冰层增长趋势的依据,且无因次温度小,冰层增长快。     

刮刀式冰蓄冷系统蓄冰槽温度特性研究

对刮刀式冰蓄冷系统蓄冰槽温度特性进行了实验研究,结果表明:水泵流量改变、冰浆发生器处阀门开度改变会对蓄冰槽内溶液温度特性产生影响,为减弱蓄冰槽内溶液的温度分层可以考虑采用机械装置增加扰动,在槽底对称布置的24个出冰口有利于槽内溶液混合均匀以及冰品的均匀分布.     

钻孔间距和布置形式对地埋管管群传热影响的研究

建立地源热泵管群传热模型,通过数值模拟方法研究钻孔间距和布置形式对管群传热的影响。研究结果表明:钻孔间距增大能够明显减缓管群区域热效率的衰减,叉排布置比顺排布置更优;对于给定数量和钻孔间距的管群,其钻孔布置区域的周长与面积比越大,整个地埋管换热器的效率也就越高。研究结果对于地源热泵地埋管管群的优化设计具有一定的指导意义。     

沉浸式蒸发盘管蓄冰机理分析及仿真

从沉浸式蓄冰盘管蓄冰过程讨论出发,分析冰的生长机理,并应用流体Fluent软件对蓄能空调中蓄冰槽的蓄冷过程进行数值模拟,根据仿真结果改进实验方案,对小型蓄能空调机组的应用研究提供数据参考.     

外融冰系统中开式蓄冰槽设计

通过具体设计实例分析了外融冰系统中开式蓄冰槽的技术特点和应用要求,对开式蓄冰槽的设计要点进行总结说明,并通过建立该蓄冰槽的流场模型、融冰实验台及简化取冷数学模型,验证该蓄冰槽中的流场和融冰性能。     

结冰厚度对盘管、普通冰球及蕊心冰球热阻的影响

蓄冷设备在制冰过程中,随着结冰厚度的增加,热阻增大。为了分析结冰厚度对蓄冰装置的影响,以传热理论为基础,通过结冰末期的热阻与结冰一半时热阻的对比,分析了三种蓄冰装置受结冰厚度的影响程度,并对这三种蓄冰装置做出了评价。     

动态冰蓄冷系统的融冰放冷特性

在自行建设的动态冰蓄冷中试系统基础上,以蓄冰槽为研究对象,研究融冰放冷的动态特性.通过改变蓄冰槽初始蓄冰量、末端负荷、冷冻水流量以及蓄冰槽回水速度等参数,分析了蓄冰槽内取水温度变化规律,得到了融冰放冷速率曲线.     

砖冰机制冰桶排列方式对制冰池流场影响分析

采用CFD方法对大型砖冰机制冰桶排列方式对制冰池流场的影响进行了模拟分析,现有制冰桶为顺排,制冰池内制冰桶横向间隔内的盐水速度几乎为零,制冰桶纵向间隔内盐水呈层流分布,流速约为0.3~0.4m/s。制冰桶横向间隔内盐水温度高于纵向间隔;整个制冰池盐水速度分布和温度分布很不均匀,盐水阻力相对较小。采用叉排制冰桶可显著改善制冰池内盐水流场,速度分布和温度分布相对更均匀,且盐水温升相对较大,盐水与冰水换热效果更好,但盐水阻力也有所增大。通过对制冰池内盐水流体的速度场、温度场和压力场的对比分析,为砖冰机制冰池制冰桶排列方式的优化提供建议与参考。     

直接蒸发内融式冰蓄冷空调的蓄冷和释冷特性

直接蒸发内融式冰蓄冷空调是一种新型的冰蓄冷技术,具有换热效率高,使用范围广等优点。在一台变频空调器基础上,通过新增蓄冰槽、换热盘管、控制阀等设备改制构成直接蒸发内融式冰蓄冷空调实验系统。研究了该空调系统的蓄冰和融冰两个过程中的冰槽内盘管传热特性和系统的运行动态特性,得到了蓄冷和释冷过程的性能曲线。实验结果表明,直接蒸发内融式冰蓄冷空调系统可以使得空调电力负荷转移率达到23%左右。通过实验研究可以为直接蒸发内融式冰蓄冷空调产品的设计开发提供实验基础,具有一定的工程运用价值。     

Effects of storage on flow and heat transfer characteristics of ice slurry

The effect of storage on flow and heat transfer characteristics of ice slurry was investigated experimentally. After ice slurry had been stored in the storage tank, variations in ice particle size were measured using a microscope, and diameter distribution and average diameter determined. The ice packing factor, Reynolds number and storage time were varied as experimental parameters. The pressure drop and heat transfer coefficient were measured when the ice slurry flowed in the horizontal tube. For laminar flow, the ratios of pipe friction and heat transfer coefficient decreased with storage time. For more than 12 h storage time, the ice slurry could not flow in the tube. The adhesion between ice particles seemed to cause a blockage in the tube. On the other hand, for turbulent flow, the pipe friction and ice slurry heat transfer coefficients were similar to that of the ethanol solution, and the storage effect was insignificant.     

蓄冰池保温厚度的测算

本文分三种情况测算了在冰蓄冷空调系统中经常用到的钢筋混泥土蓄冰池保温层的厚度,根据工程的设计施工经验,提出了合理的蓄冰池结构及置放方式,可以减少蓄冰池热量损失,达到节能、节省空间和节省费用的目的。     

关于钢筋混凝土蓄冰池保温厚度的测算

本文分三种情况测算了在冰蓄冷空调系统中经常用到的钢筋混凝土蓄冰池保温层的厚度,根据工程的设计施工经验,提出了合理的蓄冰池结构及置放方式,可以减少蓄冰池热量损失,达到节能、节省空间和节省费用的目的。     

Ice-slurry production using direct contact heat transfer

An ice slurry generation system was developed using direct contact heat transfer between water and the coolant, Fluroinert FC-84. The location of the coolant nozzle is an important design consideration to avoid clogging due to freezing of water. An ice fraction of up to about 40 percent was obtained with the nozzle located at the bottom of the ice slurry tank and the jet directed upwards into the water. Two simplified model were developed to extract the heat transfer coefficient between the coolant drops and the water. The first model requires as input the average drop diameter and the residence time while the second model uses the measured drop diameter distribution. The estimated heat transfer coefficients are much smaller than those computed using single-sphere correlations.     

LNG储罐主容器泄漏时外罐壁的传热特性

以一种LNG储罐为研究对象,利用有限单元法(FEM)分析了在主容器泄漏时的混凝土外罐壁的传热特性,研究了泄漏发生时外罐壁温度随着时间的变化过程,泄漏发展后的外罐壁的温度分布和热流密度,以及热保护边角(TCP)对于外罐壁传热的影响,指出了外罐壁热传导达到稳定后的传热特性.     

冰浆在蓄冰池中的贮存与融化研究进展

总结分析现有的蓄冰池中冰浆贮存及融化在机理、数学模型、实验方面的研究成果,在此基础上,实验研究了入口冰浆流量、冰浆固相含量、初始液面高度和进水管布置等参数对贮存和融化特性的影响。实验发现使用高浓度的二元溶液、高含量冰浆固相以及增大进口流量都可以使冰浆贮存更均匀;增大融冰溶液的流量、增加扰动以及均匀喷撒溶液是避免"沟道"效应从而实现快速、均匀融冰有效手段。     

Continuous formation of slurry ice by cooling water–oil emulsion in a tube

Water-silicone oil emulsion with an additive, (C₂H₅O)₃SiC₃H₆NH₂, was examined as a heat storage material. A spiral tube used as a heat exchanger was immersed in a low temperature bath and the emulsion was circulated in the tube to make ice continuously. Ice was separated from the ice–liquid suspension in an outlet tank. The amount of formed ice, the temperatures of the inlet and the outlet of the heat exchanger, and the temperatures in the tube wall were measured and the overall heat transfer coefficient and the heat flux through the tube were calculated. Experiments were carried out, varying the flow rate, the temperature of cooling brine, and the thickness of tube wall. The condition under which slurry ice was formed continuously without adhesion of ice to the cooling wall was clarified. Though decrease in the thermal resistance of the tube increased the rate of ice formation or raised the brine temperature, it narrowed the range of the flow rate and of the brine temperature in which slurry ice was formed continuously.