Study On Heating Performance Of A New Type Of Prefabricated Thin Floor Radiation

With the progress of science technology and the improvement of productivity,the society has achieved steady development,the scale of urbanization has further increased,people tend to pursue better thermal comfort experience,and the building energy consumption has also increased significantly.Our country already had more mature floor heating technology,China has a relatively mature floor heating technology,as the same time,low temperature radiation heating terminal compared to other air-conditioning terminal,with many advantages like high-comfortability,easy mounting,energy-saving and other.But also in the existing heating technology,there are some problems,such as long response time,slow temperature rise that is difficult to meet the requirement of intermittent operation and restricts the application of radiant heating in southern China.In this context,this paper proposes a new prefabricated thin floor heating terminal.The experimental platform is located in Chongqing University's laboratory 415 room and a new type of prefabricated thin radiant panel is laying in the floor,and take it as the research object,theoretical analysis?the experimental study and numerical simulation are combined to conduct a research on the heating performance of the new radiant heating terminal.This paper is aimed at the new radiant heating terminal with the pipe diameter is16mm,tube distance is 150mm.When the water supply temperature respectively is 45??40??35?and the system is stable,the average temperature of indoor air,severally is19.92?,19.14?and 16.82?,the radiation surface average temperature,severally is26.0?,24.3?and 21.3?,effective heat dissipation per unit area severally is 59.25W/m2,44.56 W/m2,34.66 W/m2;Then under experimental conditions of the flow rate of water in the pipe is respectively 0.8 m/s,1 m/s and 1.2 m/s and the system is stable,the average temperature of indoor air,severally is 19.14?,19.57?and 19.62?,the radiation surface average temperature is 24.33?,24.71?and 24.96?,the effective heat dissipation per unit area are 44.56 W/m~2,47.06 W/m~2,49.08 W/m~2.Water supply temperature has a lager influence on the comfort parameters,effective heat dissipation and response time.When supply water temperature is 35?,the indoor air temperature increase per unit time is 2.13?/h,and when it is 45?the indoor air temperature rise per unit time is 3.66?/h,which is 4~6 times of the conventional heating floor system,the new prefabricated thin heating terminal has the advantages of fast response time.Then,building a numerical model is for simulation analysis,and the experimental results are used for verification and correction.The error of the model is reduced to within15%,and then build a radiant panel's numerical model with 10mm pipe diameter on this basis and propose some proper pipe instances.Finally,the pipe instances are determined to be 60mm,80mm and 100mm,and use the simulation software to analysis.The results show that the new type of prefabricated thin radiation with a pipe diameter of 10mm in the same simulated room had good heating performance,and the indoor air average temperature reach above 16?which meet the indoor design temperature requirements.Finally,the parameters affecting the effective heat loss per unit area of the radiation system are analyzed by using SPSS software and other methods,and obtain the quantitative relationship between multiple factors and effective heat loss per unit area of prefabricated thin floor heating system and the corresponding empirical formula are obtained.An evaluation system is based on BP neural network model to evaluate the heating performance characteristic of the radiation terminal.