毛细管网辐射供冷的传热分析及热舒适性研究

发布时间：2018-03-21 18:20

  本文选题：毛细管网空调系统　切入点：热舒适性　出处：《东华大学》2013年硕士论文　论文类型：学位论文

【摘要】：随着社会经济的不断发展,人们对室内热舒适性要求也在不断提高,空调能耗十分巨大。对于传统空调系统而言,仍存在着一些问题如：温湿度耦合处理带来的损失、冷表面滋生霉菌、对流吹风感、盘管送风的噪音以及室内重复安装两套环境调节系统等,如提高舒适程度必然造成了更大的能耗损失。 毛细管网空调系统基于温湿度独立控制技术和长波辐射原理,结合置换通风后能有效地提高室内空气品质,实现能源的梯级利用,是一种舒适,节能、环保的空调系统。 本文首先建立毛细管微环境的传热物理模型,对整个空调系统进行传热分析,利用CFD软件进行数值模拟,探讨不同管间距、抹灰材料、供回水温差等因素对毛细管辐射顶板的温度分布及换热量的影响情况；建立了顶板式毛细管辐射末端空调房间的物理模型,运用CFD软件进行数值模拟,获得不同顶板温度、送风方式及送风温度下,供冷房间内的温度场、速度场的分布情况,同时采用Matlab软件对PMV-PPD评价指标公式进行编程,得到辐射空调系统中人体的热舒适性情况；最后以一毛细管网空调系统房间作实验验证,进行温度场、速度场和相对湿度的测试,并对测试数据进行了分析,与上述的数值模拟结果进行对比。结果显示,实测值与数值模拟值基本吻合,证明了利用数值模拟的方式对毛细管网空调系统热环境进行预测是可行的。 计算结果表明：管间距、抹灰材料、供水流速及温度对顶板的换热性能影响显著,最优的参数取值可保证顶板换热能力最强,热流密度大于60w/m2。在探讨人体热舒适性时,本文认为热舒适性指标PMV取-0.5-+0.5为最佳,即保证预测不满意率(PPD)在10%以内,结果显示采用下送上回的送风方式要优于其它送风方式；顶板温度为影响人体热舒适性的主要因素,不超过20℃时预测不满意率小于10%。 本文的研究一定程度上弥补了现有毛细管网空调系统在应用中遇到的问题,可为行业内设计、施工提供一定的参考,毛细管网空调系统运用于舒适性要求高的高档办公、住宅楼具有很大的发展前景。
[Abstract]:With the development of social economy, the requirement of indoor thermal comfort is increasing, and the energy consumption of air conditioning is very great. For the traditional air conditioning system, there are still some problems such as the loss caused by coupled treatment of temperature and humidity. Cold surface breeding mold, convection blowing sense, the noise of coil air supply, and indoor repeated installation of two sets of environmental regulation systems, such as increasing the degree of comfort will inevitably lead to greater energy loss. Capillary net air conditioning system based on temperature and humidity independent control technology and long wave radiation principle, combined with displacement ventilation can effectively improve indoor air quality and realize cascade utilization of energy. It is a comfortable, energy saving and environmental protection air conditioning system. In this paper, the heat transfer physical model of capillary microenvironment is established, and the heat transfer analysis of the whole air conditioning system is carried out. The numerical simulation is carried out by using CFD software, and the different tube-spacing and plastering materials are discussed. The effect of temperature difference of water supply and backwater on the temperature distribution and heat transfer of capillary radiation roof was studied, and the physical model of the top plate capillary radiation end air conditioning room was established, and the different roof temperature was obtained by numerical simulation with CFD software. The distribution of the temperature field and velocity field in the cooling room under the air supply mode and the air supply temperature. At the same time, the PMV-PPD evaluation index formula is programmed by Matlab software, and the thermal comfort of the human body in the radiation air conditioning system is obtained. Finally, the temperature field, velocity field and relative humidity are tested with a capillary air conditioning system room, and the test data are analyzed and compared with the numerical simulation results mentioned above. The results show that the temperature field, the velocity field and the relative humidity are measured. The measured values are in good agreement with the numerical simulation values, which proves that it is feasible to predict the thermal environment of the capillary air conditioning system by numerical simulation. The results show that the pipe spacing, plastering material, water flow rate and temperature have significant effects on the heat transfer performance of the roof, and the optimum parameter values can ensure the heat transfer capacity of the roof is the strongest, and the heat flux is greater than 60w / m2. When the thermal comfort of the human body is discussed, In this paper, the optimum thermal comfort index (PMV) is -0.5-0.5, that is to say, the predicted unsatisfactory rate is less than 10%. The results show that the air supply mode with downward return is superior to other air supply methods, and the roof temperature is the main factor affecting the thermal comfort of human body. The predicted unsatisfactory rate is less than 10 at 20 鈩，

本文编号：1645009