用于非冷藏生鲜食品运输过程的多层瓦楞纸盒热性能模拟

Simulating study on thermal performance of multilayer box for fresh food transportation

通过建立并验证食品非冷藏运输过程中多层保温盒传热的三维模型,揭示了包装盒内辐射传热是除了传导外的关键作用因素。通过减少辐射,使食品在贮藏的前30 h内表面的铝箔添加量降低10%以上。将最初冷冻的凝胶包放在盒的中心能够明显延迟其融化,使食物的保存时间加倍。结果分析表明:盒壁的导电性和盒内表面的发射率和凝胶袋的发射率是影响性能的关键参数,而对流换热系数的影响则不太显著。

In this paper,by establishing and validating a three-dimensional model of heat transfer in multi-layer heat preservation boxes during non-refrigerated food transportation,the key role of radiation heat transfer in packaging boxes is revealed besides conduction.By reducing radiation,the amount of aluminum foil added on the inner surface of food during the first 30 hours of storage was reduced by more than 10%.Putting the initially frozen gel pack in the center of the box can obviously delay its melting and double the storage time of the food.The sensitivity analysis shows that the conductivity of box wall,the emissivity inside the box surface and the emissivity of the gel bag are the key parameters affecting the performance,while the influence of the convection heat transfer coefficient is not very significant.