直接蒸发式管外结冰过程的数值求解和实验研究

就直接蒸发式管外结冰槽结冰过程进行了数值模拟求解，实验研究证明模拟结果比较理想，为蓄水槽的蓄冰性能研究和系统的设计选用提供了依据。     

基于内融冰的蓄冰槽蓄冰和融冰模型

分析了内融冰顺排盘管式蓄冰槽蓄冰过程中的相变传热，提出简化假设，并在此基础上建立了管束模型。利用热阻网络法，对模型进行计算分析。在改变蓄冷槽换热管的材料，管径，管间距及不同进口参数的情况下，分析了蓄冷槽结构和工况对蓄冰，融冰性能的影响。     

脱冰排管蓄冷器

介绍了脱冰排管蓄冷器的结构和工作原理，及其结构冰蓄冷、脱冰和融冰供冷的过程和特点，对比冰球蓄冷和冰盘管蓄冷方式，指出这种方式的优越性，提高结冰速率，降低制造成本，省去板式换热器等。     

外融式冰盘管蓄冷动态特性研究

分析外融式冰盘管的工作过程，并对其蓄冰过程建立了数学模型。利用该模型模拟冰盘管的蓄冰过程，其结果与实测值相近。该模型可为冰盘管蓄冰系统的设计提供理论根据。     

螺旋管式相变蓄冰装置的结构优化

对冰蓄冷系统中,螺旋管式蓄冰装置相变蓄冰过程进行研究。采用第三类边界条件建立传热方程式,可以较好地描述相变传热过程。建立可靠的模拟模型,对螺旋管相变蓄冰过程进行数值模拟,模拟结果表明,螺旋管中心容易产生相变死区,蓄冷材料利用率不高;采用螺旋管中间加装直管段的方式进行优化,模拟结果表明,同等蓄冰条件,溶液出口温度同比提高1.5℃;相变蓄冷4 h,结冰质量由9.07 kg同比提高到10.45 kg,相变死区问题得到解决,蓄冷材料利用率提高。综合表明采用加装直管段优化方式具有合理性。     

外融式冰盘管取冷特性的实验研究

介绍了在外融冰式冰盘管实验台上所作的外融冰槽取冷特性实验研究，揭示了影响外融冰槽热工特性的流量，进口水温，负荷强度，初始蓄冷量，取冷水流进出口方式等主要因素及其作用规律，评论了冰盘管蓄冷技术的发展和应用前景。     

伴随自然对流叠置圆管外蓄冰特性的试验研究

针对伴随自然对流效应的管道蓄冰问题，将立方体空间内水平叠置三圆管外的蓄冰过程作为研究对象，研究了恒壁温和水温变化引发的自然对流及密度反转条件下的圆管外蓄冰情况。调查了在高于或低于密度逆转温度点的不同初始温度下自然对流形成的情况，及其对水平叠置恒壁温三圆管外冰层形成过程的影响。研究了密度反转和等间距三管间相互作用下，围绕上，中，下三管外蓄冰过程蓄冰量的变化规律。     

翅片管换热器蓄冷过程特性的实验研究

根据盘管在蓄冰期换热系数较低的情况,提出采用翅片管做蓄冰换热器的方案,并以片距12.7mm的翅片管换热器进行了实验,得到了翅片管换热器蓄冷周期的制冷量变化规律、结冰界面的推进过程以及冰层厚度的分布情况,对后续翅片管蓄冰槽的研究有参考意义.     

盘管式内、外融冰系统技术运用差别分析

通过分析盘管式蓄冰系统内、外融冰方式的技术特点,总结了两者在系统流程、设备要求、控制策略、适用场合等方面的差别,研究了冰盘管式蓄冰系统的技术规律.     

成核添加剂对板单元蓄冰过程的影响研究

在封装式蓄冰技术中,为提高过冷水开始结冰的温度,需向水加入合适的成核添加剂。经过对若干添加剂的实验探索,找到了一种较为有效的成核添加剂。给出了非匀速冷却系统下结冰概率的计算方法,并将其与板单元蓄冰装置的数学模型相结合进行数值求解,定量地预测了加入成核添加剂对蓄冰过程过程的影响。     

Co-simulation of a HVAC system-integrated phase change material thermal storage unit

A co-simulation environment, consisting of a detailed mathematical model of a thermal energy storage unit which is incorporated with an EnergyPlus simulation model of a full building HVAC system, is described. The two models are integrated using the user-defined plant component feature in EnergyPlus and the Building Controls Virtual Test Bed (BCVTB) environment. The thermal energy storage unit, which consists of encapsulated phase change material in a series of flat plates and a heat transfer working fluid (water), is modelled using a transient one-dimensional forward finite difference method. The thermal storage model is executed within MATLAB and is verified against experimental data, showing a discharging heat transfer accuracy to within 2.5%. The building model, which incorporates a retrofitted ground source heat pump system within a thermally massive building, is simulated in the EnergyPlus environment. The co-simulation arrangement allows for in-depth analysis of the integrated system under dynamic operating conditions, which is currently not possible within the EnergyPlus environment. Moreover, the overall adopted approach, based on generic integration of a detailed mathematical model, using a third party generalised programming environment, into an established building simulation environment, serves as a successful exemplar for other researchers and practitioners working in the field.     

适于系统仿真的表冷器模型及其实验验证

从热力学和传热传质的基本原理出发，以TRNSYS为仿真平台，建立了表冷器动态数学模型，并对其进行了实验验证，结果表明该模型仿真结果精度较高、可靠性较好，适合于系统仿真研究。     

相变热回收式通风装置的研发及性能测试研究

随着建筑节能标准的提高,建筑外窗气密性要求不断提高。靠门窗渗透的自然通风量已不能满足室内空气质量的要求。采用机械通风的方式引入新风也存在着通风量的大小及通风模式会影响建筑节能的问题。为此,将相变蓄能技术应用于民用建筑的机械通风系统,研发出一种相变热回收式通风装置,以更好地解决室内空气质量和节能问题。所研发装置利用相变材料的蓄、放热性能,通过交替运行的通风模式,以及通风装置的不断循环,实现无管道式的相变热回收式建筑通风系统。主要采用实验研究的方法,在人工气候室内对研发样机进行了2个蓄、放热周期(4种工况)的测试研究。结果表明,相变热回收式通风装置的进口温度恒定、出口温度随时间不断变化,不同时间阶段呈现不同的变化趋势。第一时间阶段,即初始阶段,出口温度随时间变化剧烈,表明相变蓄能装置进入相变阶段,相变潜热量不断增大。第二时间阶段,即相变阶段,出口温度随时间呈线性变化,表明相变蓄能装置温度恒定,与空气流体发生稳定的相变传热。第三时间阶段,即完成阶段,出口温度变化小,基本接近进口温度,表明相变蓄能装置相变结束。从相变传热机理进行分析,固-液相变传热过程主要包括液态显热蓄(放)热、相变潜热蓄(放)热和固态显热(蓄)放热3个阶段,实验过程中出口温度随时间变化呈现出的几个时间阶段的不同规律,与相变传热机理有关联且相互对应。相变热回收式通风装置的风量恒定、不同进口温度工况下的对比数据表明,进口温度与相变温度的温差越大,初始阶段的出口温度变化越剧烈,相变阶段的出口温度线性变化率越大,且蓄、放热效率越高。进口温度与相变温度的温差约17℃时,蓄、放热效率分别达到56.2%(蓄)、50.8%(放)。     

Numerical simulation of phase change heat transfer of a solar flat-plate collector with energy storage

The technical feasibility of an innovative solar collector is studied in this paper. A phase change material (paraffin) is used in the solar collector to store solar energy. This type of system combines both collection and storage of thermal energy into a single unit. The major advantages of the phase change stores are their large heat storage capacity and isothermal behavior during the melting and solidifying processes. A negative aspect of paraffin is its low thermal conductivity which increases the melting and solidifying time for paraffin energy storage. In this paper, new aluminum foams infiltrated with paraffin are presented. It presents a two dimensional model describing the melting and solidifying processes of paraffin while accounting for both phase change heat transfer and natural convection. Apparent heat capacity method was used to simulate the melting and solidifying processes of paraffin. The simulation results show that the motion of the hot liquid paraffin plays an important role in increasing the heat transfer between paraffin and top surface of solar collector. The shape profile of the pure paraffin solid-liquid interface is determined by the synergistic relationship between its temperature and velocity field. Though aluminum foams impregnated with paraffin will limit motion of the hot liquid paraffin, the heat transfer ability is greatly improved. The distributions of the temperature in the paraffin with aluminum foams are more homogeneous compared with that of the paraffin without aluminum foams. Thus, use of aluminum foams infused with paraffin improves heat transfer and enhances paraffin’s melting and solidifying rates.     

冰晶式蓄冷系统蓄冰传热过程初探

通过对其成冰机理和传热过程的分析,建立了冰晶式蓄冷系统的简化数学模型,并利用制冰晶蒸发器实验台对计算结果进行了验证。     

定形相变墙体传热性能和力学性能的实验研究

利用液体石蜡-46#石蜡、液体石蜡—月桂酸和癸酸—肉豆蔻酸3种相变材料混合物分别与高密度聚乙烯混合制备定形相变材料.通过直接混合法把定形相变材料加入水泥砂浆制备定形相变墙体.实验研究了相变墙体和普通墙体的传热性能和力学性能.实验结果显示:定形相变墙体表面温度和热流均低于普通墙体;热物性不同的相变材料随着墙体中含量的增加...     

Effects of wallboard design parameters on the thermal storage in buildings

The phase change material (PCM) could be added to the wallboard to increase the thermal mass to decrease in indoor temperature fluctuation and improve thermal comfort. In this study, experimentally validated simulation was performed to investigate the effects of various parameters of PCM including the nominal average phase change temperature, its range, the convective heat transfer coefficients and the wallboard thickness on the thermal storage performance of the wallboard such as the thermal energy storage and the time shift.It was found that the average phase change temperature should be close to the average room temperature to maximize the thermal heat storage in the wallboards. The phase change temperature should be narrow to maximize the thermal heat storage in the PCM wallboards. The thermal heat storage increased with the convective heat transfer coefficient, and the optimal average phase change temperature to maximize the storage shifted a bit to a higher temperature with it. The time shift was found to decrease with the convective heat transfer coefficient and the phase change temperature range.     

Numerical and experimental study on heat pump water heater with PCM for thermal storage

An air source heat pump water heater with phase change material (PCM) for thermal storage was designed to take advantage of off-peak electrical energy. The heat transfer model of PCM was based upon a pure conduction formulation. Quasi-steady state method was used to calculate the temperature distribution and phase front location of PCM during thermal storage process. Temperature and thermal resistance iteration approach has been developed for the analysis of temperature variation of heat transfer fluid (HTF) and phase front location of PCM during thermal release process. To test the physical validity of the calculational results, experimental studies about storing heat and releasing heat of PCM were carried. Comparison between the calculational results and the experimental data shows good agreement. Graphical results including system pressure and input power of heat pump, time-wise variation of stored and released thermal energy of PCM were presented and discussed.