环境因素对冷库地坪立柱散冷影响的数值模拟

Numerical simulation of the influence of environmental factors on the column dissipating cooling of cold storage floor

为防止冷库地坪立柱散冷导致地坪局部冻胀,提高冷库科学管理水平,降低建筑能耗,建立了某冷间通风地坪及立柱模型,以地坪及立柱散冷量、立柱附近温度为指标,探讨了室内温度、室内对流换热系数、通风管进口风温、风速对散冷量及温度的影响。结果表明:立柱加速散冷耗,室内温度越低,散冷量越大,地坪温度越低,对流换热系数对此影响不明显;通风管进口通风温度越高、风速越大,散冷量越多,地坪温度越高,通风管进口风速>1 m/s时对散冷量和温度的影响减缓。当通风温度为279 K、室内温度≥246 K时,地坪无冻胀区,此时需开启机械通风装置维持通风管进口风速≥1 m/s;当通风温度增加至281 K、室内温度≥240 K时,无需机械通风,维持通风管进口风速≥0.5 m/s可预防地坪冻胀;当通风温度上升至283 K、室内温度≥240 K时,无需机械通风,维持通风管进口风速≥0.3 m/s可预防地坪冻胀。立柱保温模型表明立柱散冷量明显减少、地坪温度提高。

Modeling of the ventilation floor and the column of a cold storage was investigated.The aim was to prevent the local frost heaving of the floor caused by the scattered cooling of the floor column of the cold storage,as well as to improve the scientific management level of the cold storage and reduce the building energy consumption.Using the cooling capacity of the floor and column,and the temperature near the column as indexes,the influence of the indoor temperature,indoor convective heat transfer coefficient,inlet air temperature of ventilation pipe and wind speed on the cooling capacity and temperature were studied.The results showed that the cooling dissipation was accelerated by the column.The lower the indoor temperature,the greater the cooling capacity and the lower the floor temperature,while the effect of convective heat transfer coefficient were not significant;The inlet air temperature and the wind speed could affect the cooling capacity and floor temperature positively.The effect on the cooling capacity and temperature was reduced when the wind speed was greater than 1 m/s.It was also found that when the ventilation temperature 279 K and the indoor temperature≥246 K,no frost heaving area on the floor could be detected.Moreover,it was necessary to open the mechanical ventilation device to maintain≥1 m/s;when the wind temperature increased to 281 K and the indoor temperature≥240 K,the mechanical ventilation was not necessary,and the floor frost heaving could be prevented by maintaining the wind speed≥0.5 m/s;when the wind temperature rose to 283 K and the indoor temperature≥240 K,the floor frost heaving could be prevented,and there was no need for the mechanical ventilation and the floor frost heave could be prevented by maintaining the wind speed≥0.3 m/s.The thermal insulation model of the column showed that the cooling capacity of the column was significantly reduced and the floor temperature increased.