Study On The Effect Of Heat Storage On Indoor Thermal Environment In Residences With Concrete Components

Heating and cooling has become the main energy consuming in most countries, more and more attention has been paid on energy saving. Thermal storage is one of the most important elements in solar buildings. Appropriate thermal storage and system design can effectively bring down building energy consuming. Concrete is the main construction material in our country. Concrete is a sensible heat storage material with big heat capacity, charge/discharge characteristics of which can effectively improve indoor thermal environment. But few studies have been found about thermal storage in conctete buildings, most of which have ignored the effect of charge/discharge characteristics of thermal mass on indoor thermal environment. Few conclusions can be put into project and instruct design.In this paper, indoor thermal environment with charge/discharge characteristics of concrete thermal mass has been studied. Formula of equivalent heat supply considering thermal storage effect in floor heating residences has been put forward. Effect of outer heat preservation on heat release performance of the wall at night has been discussed. Conclusions are meaningful and practical for optimizing thermal storage components, directing project design and spreading the utilization of thermal storage in buildings.Both experiment and theoretics research has been taken in this paper, conclusions are as below:The neglect of charge/discharge characteristics of thermal mass in conventional design of heat supply in radiant floor heating system has resulted in many problems such as over designed heat supply , indoor overheat , low relative humidity and so on. Based on a computing model of floor heating residences, indoor thermal environment and heat distribution under the effect of heat charge/discharge, operation control and solar radiation has been concluded. Concept and formula of equivalent heat supply has been put forward which indicate that actual heat supply will be equal to the sum of design heat supply and equivalent heat supply. Recommend coefficient has been given taken Dalian as an example. Computed according to the new method, design heat supply can be reduced to 37% in cloudy day and 43.3% in sunny day, energy saving effect is very obvious.In Tromb wall solar house, effect of concrete wall on indoor temperature swing and attenuation of temperature wave is very obvious. While the outdoor air-temperature swing exceeds 10℃, indoor air-temperature swing belows 3℃. In the experiment, maximal difference in temperature between inner surface and outer surface of the 300mm wall exceeded 10℃. Heat storage and collector efficiency varies adversely according to solar radiation. Factors such as thickness, material, absorptance of the wall and permeation of the glass cover all have big influence on heat storage and collector efficiency. There exsisted an optimal thickness of the wall, which can make the best of heat storage and collector efficiency. Most of the heat stored in conventional Trombe wall during the daytime has been lost to the outside at night without heat preservation. Heat preservation on the outside surface of the wall has effectively improved heat release performance of the wall at night, heat supply to the room has increased too.As to the position, efficiency of thermal mass in building slab with heat sources in it is higher than heat storage in wall; As to the way of heating, efficiency of floor heating system with heat sources in the thermal mass is higher than collecting system with heat sources irradiating to the outer surface of the wall, and temperature swing of which is smaller too.