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毕业设计英文资料翻译 Translation of the English Material of Graduation Design学生姓名: x 学 号 : x Name: x Number: x 班 级: x Class: x 所在学院: x College: x 专 业: 建筑环境与设备工程 Profession: Building Evironment and Equipment Engineering 指导教师: x Tutor: x 2015年 3 月 10 日Selection of Weather Parameters for AirConditioning System Design for Buildings with Long Thermal LagAbstractTwo building factor一a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling loadhave impact on the instantaneous heat input and instantaneous cooling loadSo the two factors should be taken into account when selecting the weather parameters for air-conditioning system designThis paper developed a new statistic method for the rational selection of coincident solar irradiance, dry-bulb and wetbulb temperaturesThe method was applied to historic weather records of 25 years in Hong Kong to generate coincident design weather dataAnd the results show that traditional design solar irradiance,drybulb and wetbulb temperatures may be significantly overestimated in many conditions,and the design weather data for the three different constructions is not kept constantKey words:building construction;thermal lag;system capacity;design weather data;air-conditioningAir-conditioning design weather conditions,including dry-bulb temperature,moisture content and solar irradiation,are essential and fundamental data for the design of building air-conditioning systems,They simultaneously act on a building,and are driving potentials of heat transfer through building envelope and direct mass exchange by infiltration and ventilation12, However, because of the heat inertia of the building envelops,a relationship of thermal attenuation and delay with the time developing between fluctuation range of heat transmission and temperature through the building envelops and that of outdoors,and it depends on the heat capacity of the building envelopThis will greatly impact on the heat transfer through building envelop:the heat input at the design hour can not be simply decided by the heat transfer though building envelope at the design hour,the impact of the heat transfer though building envelope because of the thermal attenuation and delay before the design hour should be considered3Generally, solar irradiation should have a significant contribution to building cooling loads,especially for passive or active solar cooling buildings4However,the current design solar irradiance data do not simultaneously occur with the coincident dry-bulb and wet-bulb temperatures for air-conditioning system designTherefore,this study is first aimed at developing a method for rational selection of coincident solar irradiation,dry-bulb and wet-bulb temperatures. The second objective is to apply this novel method to historical hourly weather data observed in Hong Kong to generate the coincident design weather conditions. These selected design weather data can be used to design an air-conditioning system that can match system reliability desired for a building with thermal time constant more than 1 hour1 Theoretical ModelWhen calculating the cooling load of a building or room with a thermal lag of more than one hour,the rts method is suitable, Thus:1) Calculate 24 h profile of component heat gains, for conduction,first account for conduction time delay by applying conduction time series2) split heat gains into convective and radiant parts53) Convective part becomes the instantaneous cooling load4) Apply appropriate radiant time series to radiant part of heat gains to account for time delay in conversion to cooling load5) In order to simplify the design formulas and improve the computational accuracy,the weather data of the twenty hours in a day act on the cooling load of each hour1Based on the concept of equivalent temperature,a theoretical model is developed6For a building or room whose thermal lag is more than one hour,hourly cooling load Q(k) may be expressed byWhere Te(k) is the equivalent temperature;twb the wet-bulb temperature,;tdb the dry-bulb temperature,;Et is the total irradiance,W/m2, Ed the diffuse irradiance W/m2;ED is the direct irradiance,W/m2;rSHGC is the ratio of SHGC at any incident angle to SHGC(O)at the normal angle,SHGC is the direct solar heat gain coefficient as a function of inddent angle .Aj,Bj, Cj,Dj are the characteristic parameters of a building or roomFor a given building or room,characteristic parameters Aj Bj Cj Dj can be derived by using the RTSCTS and other parameters,Therefore,they reflect the thermal characteristics of buildings,and describe the effect of wet-bulb temperature and total solar irr
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