辐射供冷系统末端形式对比及发展研究

介绍几种辐射供冷空调的末端形式,比较冷吊顶、楼板辐射供冷、毛细管席的供冷能力、热舒适性、能耗及投资等方面的不同,并建议完善辐射供冷系统试验研究方法,着重进行拥有自主产权产品的制造工艺的研究。     

基于毛细管型辐射供暖与供冷系统影响因素的研究

随着建筑节能的推广和人们对室内生活舒适性要求的提高,采用一种更先进、更节能的室内空气调节系统就显得日趋重要。毛细管型辐射供暖与供冷系统因具有舒适度高、节能效果显著、节省建筑空间等的优点逐渐被广泛采用。对以毛细管为末端的毛细管型辐射供暖与供冷系统布置形式作了介绍,分析了该系统的组成及优点。以辐射供冷为例,探讨了辐射冷系统的末端一毛细管席供冷量的影响因素。     

辐射供冷空调系统研究进展

同传统空调系统相比,辐射供冷空调系统具有舒适、节能的优点。根据辐射板安装位置的不同可分为顶板辐射和地板辐射供冷,按照实验研究和仿真研究方法对其发展现状进行了概述,并对目前存在的问题和今后的发展趋势进行了探讨和展望。     

太阳辐射对辐射地板供冷性能的影响

以长沙地区某南向设窗的实验房间为研究对象,采用EnergyPlus能耗模拟软件建立辐射地板结合风机盘管供冷空调系统的数值模型,并通过实验验证该模型的可靠性。通过规范计算及模拟分析量化不同窗墙比下太阳辐射得热对该系统中辐射地板供冷能力及风机盘管系统设计容量的影响,并提出一种在太阳负载下辐射系统容量预测的简化方法。     

西安地板辐射空调优化及室内热环境研究

在现有地板供暖设计状态下,采用有限元分析法对二维辐射地板导热微分方程进行数值模拟计算,研究不同供回水平均温度、填充层厚度、盘管间距对地面温度和热流密度的影响,分析高温冷水地板供冷系统的供冷能力和结露问题。获得保证地面不结露的地板设计参数以及表面释冷量限值;在该地板设计条件下,通过对具体房间热环境的模拟计算,得到在西安整个夏季室外温度时,该系统在供冷初期和末期可保证基本的热舒适要求,只有在供冷中期单一的地板辐射供冷不能满足人体的热舒适性,需加其他辅助空调。     

毛细管网辐射空调末端换热性能实验研究

为了研究毛细管网空调末端的换热性能,对郑州中南科莱空调设备有限公司会议厅毛细管网空调辐射系统空调末端进行了设计计算,并在该系统上进行了冬季供暖实验研究,通过分析实验数据,计算得到毛细管网辐射末端的平均换热量和综合传热系数,分别为38.95 W/m2和4.14 W/（m2·K）,与已有经验数据基本吻合,但是由于实验条件的局限性,该结果有待进一步校核。     

辐射冷板研究综述

近年来,辐射供冷空调系统因其卓越的节能性和舒适性备受学者关注和研究。然而,由于其特殊的传热特性,该系统容易发生结露现象。结露不仅对系统的正常运行产生了负面影响,还限制了其供冷能力,这在推广过程中带来了一定的困难。旨在综述当前辐射板相关的研究进展,重点包括结露现象的研究、防结露处理、辐射板供冷性能相关研究、辐射板结构优化以及相变材料的应用等方面。通过对这些研究内容的综述,旨在为进一步推广辐射供冷空调系统提供理论支持。     

单一地板辐射供冷空调方式适用区域的划分

叙述了不加置换通风等其他空气处理方式单一地板辐射供冷空调系统的局限性和可行性以及结合中国各主要城市逐时气象参数,对普通住宅建筑,划分了单一地板辐射供冷空调方式的适用区域。     

辐射吊顶空调系统的研究与应用

介绍一种新型空调系统形式——供冷、供热辐射吊项空调系统。阐述辐射吊顶空调系统的结构形式和特点,通过实验测试研究和工程应用实践表明,辐射吊顶系统可以满足采暖和制冷的要求。     

冷辐射地板系统的实验研究

为了研究冷辐射地板系统的热工性能，测试了地板辐射供冷系统的运行工况，得到了地板表面的最低温度、室内的实感温度、热流密度等参数，并初步探讨地板辐射供冷系统结露现象及防治措施，通过实验分析指出这是一种舒适、节能的供冷方式。     

Experimental performance of a thermoelectric ceiling cooling panel

An experiment has been performed to investigate the cooling performance of a thermoelectric ceiling cooling panel (TE‐CCP). The TE‐CCP was composed of 36 TE modules. The cold side of the TE modules was fixed to an aluminum ceiling panel to cool a test chamber of 4.5 m³ volume, while a copper heat exchanger with circulating cooling water at the hot side of the TE modules was used for heat release. Tests were conducted using various system parameters. It was found that the cooling performance of the system depended on the electrical supply, cooling water temperature and flow rate through the heat exchanger. A suitable condition occurred at 1.5 A of current flow with a corresponding cooling capacity of 289.4 W which gives the coefficient of performance (COP) of 0.75 with an average indoor temperature of 27°C. Using thermal comfort test data in literature for small air movements under radiant cooling ceilings, results from the experiments show that thermal comfort could be obtained with the TE‐CCP system. Copyright © 2007 John Wiley & Sons, Ltd.     

吊顶辐射冷却塔供冷系统试验研究与性能分析

通过供冷试验及TRNSYS软件模拟研究了吊顶辐射冷却塔供冷系统的运行效果,分析了气象参数、部件结构等因素对系统供冷效果的影响,并与常规供冷系统全年的运行能耗进行对比。试验与理论分析结果表明,吊顶辐射冷却塔供冷系统的有效供冷量能够满足用户供冷需要,供冷房间温度稳定且分布均匀。冷却塔供冷效果与大气湿球温度、建筑内部负荷、热交换器结构等因素有关。辐射顶板末端与冷却塔供冷匹配性高,系统全年运行时数增加,应用于需全年供冷的建筑节能效果显著。     

Numerical analysis of temperature non-uniformity and cooling capacity for capillary ceiling radiant cooling panel

Capillary ceiling radiant cooling panel is a high temperature cooling system, which could pose low energy consumption to meet thermal comfort requirements. A computational fluid dynamics (CFD) simulation study on heat transfer of chilled water flow in the capillary of ceiling radiant cooling panel was performed to attain surface temperature distributions and cooling capacities. Six influencing factors included chilled water inlet parameters, conditions of gypsum plaster and capillary mats structural parameters were considered to obtain the complicated relationships between capillary radiant panel conditions and heat transfer performance. The index of temperature non-uniformity coefficient was proposed to evaluate temperature profiles of ceiling panel surface. The results of the simulation were compared with the values depicted in ASHRAE Handbook and good agreement had been achieved. The average difference between simulation results and the values reported by ASHRAE handbook was within the region of 15%. The research results showed that temperature non-uniformity coefficient was negatively correlated with temperature of chilled inlet water (linear correlation), water velocity (correlation coefficient R = −0.85), and pipe diameter (correlation coefficient R = −0.93), but positively and linearly correlated with tube spacing. Cooling capacity was found to have negative linear correlation with temperature of chilled inlet water, covering thickness and tube spacing.     

Effect of modelling solar radiation on the cooling performance of radiant floors

When modelling buildings, solar radiation has a large impact on the thermal balance because it usually heats the rooms. In radiant systems that are used for heating and cooling buildings, solar radiation has a large influence both on indoor temperatures and on the efficiency of the radiant system.Many analyses have already been carried out in order to study how beam and diffuse radiation can be distributed in a room. One of the most difficult issues, when modelling room thermal balance, is how to simulate the solar radiation when it enters the room, which in turn depends on the reflectance characteristics of the surface finishing elements.In this study, four different radiation models have been applied in order to solve an overall detailed, dynamic thermal balance in a room with pipes embedded in the floor. Two of the models are detailed; the other two consider the radiation entering the room to be diffuse radiation. As for the behaviour of the impinging solar radiation on the covering materials in a room, measurements have been carried out to determine the reflectance coefficients, which will be used in simulations for characteristic materials used in buildings.Results of the simulations show that a simplified model, which considers solar radiation as uniformly distributed in a room, cannot be used for a detailed comfort analysis; however, when looking at the cooling output of a radiant floor system at the design stage, a simplified model can predict energy transfer to a certain level of accuracy. Moreover, results coming from combined measurements and simulations show that the reflectance characteristic of the covering materials does not affect the cooling capacity of the radiant floor systems, since the most important parameter for cooling performance is the thermal conductivity of the covering layer.     

Ceiling radiant cooling panel capacity enhanced by mixed convection in mechanically ventilated spaces

The main thrust of this research is to estimate the impact of the mixed convection effect on the cooling capacity of a ceiling radiant panel in mechanically ventilated spaces. To estimate panel cooling capacity enhancement caused by mixed convection, a verified analytical panel model was used. The simplified correlation for mixed convection heat transfer coefficient which can be easily adopted in panel cooling capacity estimation was derived from established mixed convection and natural convection correlations. It was found that the total cooling capacity of radiant panels can be enhanced in mixed convection situations by 5–35% under normal operating panel surface temperatures.     

Performance evaluation of a radiant floor cooling system integrated with dehumidified ventilation

The radiant floor cooling system can be used as an alternative to all-air cooling systems, using the existing Ondol system (a radiant floor heating system) in Korea to save energy and maintain indoor thermal comfort. Unfortunately, a radiant floor cooling system may cause condensation on the floor surface under hot and humid conditions during the cooling season. In addition, the radiant floor system does not respond quickly to internal load changes due to the thermal storage effect of the concrete mass, which is usually present in radiant floor cooling systems.This study proposes a radiant floor cooling system integrated with dehumidified ventilation, which cools and dehumidifies the outdoor air entering through the cooling coil in the ventilator by lowering the dew-point temperature to prevent condensation on the floor surface. Furthermore, outdoor reset control was used to modulate the temperature of chilled water supplied to the radiant floor, and indoor temperature feedback control was then used to respond to the internal load changes.To evaluate the performance of the radiant floor cooling system integrated with dehumidified ventilation, both a physical experiment in a laboratory setting and TRNSYS simulation for an apartment in Korea have been conducted. As a result, it was found that the proposed system was not only able to solve the problem of condensation on a floor surface but also to control the indoor thermal environment within the acceptable range of comfort. Furthermore, the proposed system improved the responsiveness to internal load changes.     

地源热泵技术在住宅中的综合应用

介绍了青岛某别墅的空调和热水供应系统的方案设计.设计方案把地源热泵技术用于住宅的空气调节、卫生热水供应和游泳池补水供水,还采用了辐射供暖与辐射供冷等节能新技术.文章详细介绍了系统流程、特点、工作原理和设计参数的选取等.     

半透明晶体硅光伏热电制冷辐射窗的性能分析

针对一种新型半透明光伏-热电制冷辐射窗（STPV-TE-RCW）,通过实验和数值模拟方法对其热电性能进行研究,建立STPV-TE-RCW计算模型,验证其准确性,并针对STPV-TE-RCW中的热电模块不同排列形式、辐射板尺寸、散热形式等进行优化分析。在考虑结构自身发电量与耗电量关系的基础上,通过分析制冷系统COP和耗电量,认为5块热电片串联2个支路并联的热电模块排列形式,高度为1 m的辐射板尺寸和强制对流的散热形式效果更好,在这种情况下,STPV-TE-RCW的耗电量与发电量之比为0.83,制冷量能承担该结构产生的60%冷负荷,辐射铝板提供的制冷量为63.4 W/m²,热电模块的COP为1.41。