机构地区: 华南农业大学工程学院南方农业机械与装备关键技术省部共建教育部重点实验室
出 处: 《西北农林科技大学学报(自然科学版)》 2016年第8期226-234,共9页
摘 要: 【目的】研究嵌入真空隔热板(Vacuum insulation panel,VIP)冷藏箱体的热工性能。【方法】采用圆热流法理论建立了箱体的传热系数计算模型,并对纯聚氨酯(Polyurethane,PU)箱体和不同VIP覆盖率箱体进行热箱法漏热试验,测定不同箱体的总传热系数并分析其保温性能的优劣。【结果】嵌入VIP箱体总传热系数的理论计算与试验测试结果整体趋势基本保持一致,表明所建立的计算模型可用于分析冷藏运输箱体的保温性能。当VIP覆盖率为87.14%时,箱体总传热系数是纯PU箱体的68.57%,保温性能提高33%左右。VIP覆盖率从48.87%增加到87.14%,箱体总传热系数相应从0.445 W/(m2·K)降低至0.336 W/(m2·K),间隙系数从1.23增大到1.36,箱体保温性能提高约25%。【结论】嵌入VIP箱体的保温性能优于纯PU箱体,箱体间隙系数、保温性能与VIP的覆盖率成正比。采用VIP隔热材料能提高冷藏运输箱体的可利用容积率,降低运输能耗。 【Objective】This paper studied the thermodynamic property of a refrigerated box using vacuum insulation panels(VIPs)as insulated sandwich elements.【Method】The heat transfer process of insulating multilayer panel was modeled using the circular flux method.Then heat leakage experiment was conducted to obtain the global heat transfer coefficients of the panel with pure polyurethane(PU)or VIPs coverage to analyze thermal performance of different boxes.【Result】The calculated heat transfer coefficients using the proposed model agreed well with the experimental data.The proposed modeling approach can be applied in the study of thermal conductivity and insulation performance of any refrigerated box.The total heat transfer coefficient of the refrigerated box with 87.14% VIPs coverage was reduced to 68.57%compared to the pure PU box,a 33%improvement was obtained.The total heat transfer coefficient was correspondingly reduced from 0.445 W/(m^2·K)to 0.336 W/(m^2·K),the gap coefficient was increased from 1.23 to 1.36,and the insulation efficiency was increased by 25%,as the coverage of VIPs increased from 48.87%to 87.14%.【Conclusion】The insulation performance of the refrigerated box with VIPs was better than that with pure PU.The gap coefficient and the insulation performance were proportional to theVIPs coverage rate.The refrigerated box with VIPs obtained optimal performance for space saving and energy efficiency.