| Since entered into the 21 st century on, because of the unique advantage of abundant, clean, low cost and renewable, solar energy has loved by people, but in the process of large-scale development and utilizat ion, the disadvantage of solar energy,the character o f unstable and significant intermittent, led to discont inuous and unstable explo it, so we must adopt the thermal storage system to adjust the problem that t ime does not match the space.In the north, the sun radiat ion intensit y is high, and in rural winter heat ing facilit ies lag behind other district and pose a safet y hazard to local residents securit y, so in the northern countryside, solar energy as a heat source,one part direct ly support heat ing for building during the day, the other part be stored support heat ing for building during the night.This heat ing method has ver y pract ical significance to indoor heat ing.This paper studied the effect of mo isture content and stress on thermal propert ies of the soil, collect ing the soil of opt imal thermal performance as the thermal storage material and sett ing up the experiment plat form of Kang t ype heat thermal storage device; By simplifying treat ment for storing heat device, the unsteady-state heat transfer model includes two-dimensio nal of thermal storage materials and the one-dimensio nal of heat transfer fluid were established. Based on Mat lab software plat form, compiling program for analyzing the temperature field of the fluid and soil in the Kang t ype heat thermal storage device.Combining of the experiment and numerical simulat ion for studying thermal performance of thermal storage device.The results indicated: with the increase of mo isture content and pressure, dry densit y increased; When the mo isture content of soil is 19%, the soil will get the maximum dry densit y of 1776 kg/m3; Thermal conduct ivit y of dry soil increases with the increase of dry densit y; Calculate ing the heat transfer model and getting the out let temperature of fluid changed with the t ime in accordance with what actual out let temperature data showed; Convect ive heat transfer coefficient, thermal storage power and store thermal efficiency showed a trend of first increase d with the increase of flow velocit y, when flow velocit y increased to 3.5 m/s, all of them changed in reducing; The convect ive heat transfer coefficient, thermal storage power and store thermal efficiency decreased wit h the increase of angle between the heat storage block; Pressure drop o f the thermal storage device linearly increased with the increase of angle; Wit h the increase of velocit y, pressure drop quickly increase d first, then slowly increased; Charge and discharge time length decreased with the increase of coefficient of thermal conduct ivit y, when the heat conduct ion coe fficient increases to 1.4 W/(m?℃), the effect of coefficient of thermal conductivit y decreased; Wit h the increase of heat capacit y and densit y, charge and discharge t ime length increased linearly. Heat input and output did not change with the change of coefficient of thermal conductivit y; increased linearly wit h the increase of heat capacit y and densit y. Wit h the increase of the coefficient of thermal conduct ivit y, Charge and discharge power increased as power funct ion; Charge and discharge power did not change wit h the increase of heat capacit y and densit y. The above research on thermal performance of Kang t ype heat thermal storage device provide the theoret ical basis for the desig n and applicat ion of the device... |
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