基于热流管单元的混凝土通风冷却效果

Concrete cooling effect by air cooling based on heat-fluid pipe element

我国当前通常采用内嵌水管通水冷却以降低混凝土温度,但在干旱地区或混凝土结构较高部分采用通水冷却施工较不方便,以空气作为冷却介质进行混凝土冷却能够较好地避免上述问题.相较于通水冷却,通风冷却施工设备较为简单,且由于空气密度较小,可采用竖直方向通风冷却.采用热流耦合单元,充分考虑风、水的沿程温度变化以及冷却管附近混凝土、远离冷却管混凝土不同的温度变化规律,进行通风冷却敏感性分析及通风冷却、通水冷却效果对比.仿真模拟结果表明:通风冷却能够较好地削减混凝土温度峰值;通风风速越快、通风温度越低、混凝土截面越小,通风冷却效果越好;选取适当的风速及通风温度,通风冷却能够达到与通水冷却近似的冷却效果.

The current usually adopted embedded water cooling pipes to decrease the temperature of con- crete, but this cooling way is not convenient in arid areas and the higher parts of concrete structure. Using air as cooling medium in concrete cooling can solve the above problems well; besides, compared with water cooling, the construction equipment of air cooling is simpler. And the vertical cooling direction can be a- dopted because the density of air is less than water. Coupled heat-fluid pipe, which can fully reflect tem- perature change law of the place near pipe or far from pipe and considering temperature changes of water and air along cooling pipes, is used to do some sensitivity analysis of air cooling and simulate temperature field of water cooling and air cooling. The simulation results show that air cooling can cut the peak of con crete temperature sufficiently; the cooling effect would be better with lower air temperature, faster air speed and smaller concrete cross-section; using appropriate temperature and speed of air, air cooling can reach the similar results of water cooling.