【作者】 付晓腾；

【导师】 刘京；

【作者基本信息】 哈尔滨工业大学 ， 供热、供燃气、通风及空调工程， 2009， 硕士

【摘要】 本课题来源于“十一五”国家科技支撑计划课题“新型节能围护结构关键技术”的子课题——“新型建筑通风技术与装置开发”中的“单换热型高效低温差换热器的研制”,该装置将在严寒和寒冷地区应用。随着社会经济的发展,空气-空气板式全热交换器以其节能和改善室内空气品质的双重功效,受到了越来越广泛的应用。但是当板式全热交换器在我国严寒和寒冷地区的冬季使用时,存在着结霜的问题,影响了它的使用效果。为了解决这一问题,本文在分析比较各种除霜方法的基础上,设计并试制了具有旁通除霜功能的板式全热交换器,并进行了实验研究和理论计算。本文在全热交换器热工性能实验台上进行了改进和完善,使之符合结霜实验的要求。分别使用叉流加逆流板式全热交换芯体和叉流板式全热交换芯体,测试了各种结霜工况下板式全热交换器的性能变化规律,对比研究了两种芯体结霜规律的异同,并通过实验检验了旁通除霜的效果。冬季板式全热交换器在全天中的运行可分为结霜发生期、结霜稳定期和融霜期三个时期。在结霜发生期,温度效率、焓效率和排风侧的风量都持续下降,进入结霜稳定期后三者保持稳定,次日白天,随着室外气温的升高而进入融霜期,三者都有所回升。本文提出了结霜临界新风温度的概念,并建立计算模型,求解了不同条件下的结霜临界新风温度。通过对结霜实验的数据进行线性回归,得到了两个关系式,其一为温度效率的下降速率与室内温度、室内相对湿度和室外温度的关系式,其二为结霜稳定期的温度效率与室内温度、室内相对湿度和室外温度的关系式。本文就低湿度场合和高湿度场合两种情况,分别讨论了板式全热交换器在我国的寒冷地区、严寒地区A区和严寒地区B区的结霜情况,并提出了旁通除霜板式全热交换器的运行策略,使之可以进行自动除霜。更多还原

【Abstract】 The subject comes from the national science and technology pillar program during the eleventh five-year plan period.It is from the subject“research and produce single high-efficiency low-temperature-difference heat exchanger”which is a sub-project of“new building ventilation technology and device development”in“key technologies of new energy Saving maintenance structure”.With the social and economic development, air-air plate total heat exchanger has been more and more widely used because of its dual role of saving energy and improving indoor air quality.But when it is used in cold regions and bitter cold regions,the problem of frosting affectes its use.In order to solve this problem, a plate total heat exchanger with bypass defrosting function has been designed and produced based on the analysis and comparison with various defrosting methods.Experimental research and theoretical calculation have been commenced with the exchanger.In this paper, thermal performance test-bed of total heat exchanger is improved with the requirements of the frosting experiment. Using cross-counter-current plate total heat exchanger core and cross-current plate total heat exchanger core, performance changes is tested in a variety of frosting condition. Frost law of the two core is comparative studied. The effect of bypass defrost is tesed by experiment.When the plate total heat exchanger run in a day, it can be divided into three periods:frost occurring period, frost stable period and frost melting period.In the frost occurring period, temperature efficiency, enthalpy efficiency and exhaust air volume continue declining. As it enter the frost stable period,the three remains stable.On the following day, with the outdoor temperature increasing,it enters the frost melting period and the three increase.In this paper, the concept of frost critical temperature of fresh air is put forward.And computing model is set up. Frost critical temperature of fresh air in a variety of conditions is calculated.By Linear regression of frost experiment data, two relations are put forward.One is the relation among temperature efficiency drop rate , indoor temperature, indoor relative humidity and outdoor temperature.And the other is the relation among temperature efficiency during frost stable period, indoor temperature, indoor relative humidity and outdoor temperature.This paper discusses applicability of plate total heat exchanger in cold regions , severe cold A regions and severe cold B regions at low humidity and high humidity places. And put forward operation strategy of plate total heat exchanger with bypass defrosting function to enable automatic defrosting.更多还原