卧式冷藏陈列柜风幕优化研究

发布时间：2018-04-29 19:32

本文选题：冷藏陈列柜 + 温度场　；参考：《天津商业大学》2017年硕士论文

【摘要】：近年来随着我国城镇化水平提高、居民生活方式转变以及人们对食品安全的重视,智能化冷藏柜需求显著增大。本文对冷藏陈列柜内部的温度分布和速度分布进行了分析和研究,通过建立数学计算模型进行数值计算,为试验提供优化指导和依据,确定了该冷藏柜较佳的风幕送风速度,风幕射流角度,并且通过试验在此角度和送风速度情况下进行试验测试,以试验来验证模拟的准确性。首先在试验中测试了冷藏柜封闭柜门情况下温度分布,在得到柜内分布较为稳定和均匀的情况下,进行进一步试验,本文研究的是体积较大型的冷藏柜,有三个柜门,打开一个柜门进行试验研究,用实验仪器测得试验冷藏柜内部温度分布。然后再进行下一步试验,在柜内放置试验用的食品包,测试柜内添加载荷情况下冷藏柜内温度场分布,先测量柜门关闭情况下柜内温度分布,试验完成后再测量柜门开启一个的时候,柜内温度场分布。最后将实验数据进行处理,并与数值模拟结果进行对比分析,得出以下结论:1.先进行数值模拟,模拟采用COMSOL软件,以非等温流体模型进行数值模拟,模拟中先以1m/s的送风速度对比分析在不同射流角度下的柜内温度和速度分布,模拟选用角度分别为5°、0°、-5°、-10°,通过对比这四种不同风幕射流角度发现以-5°倾角为最佳,送回风温度差值较小,柜内温度分布相对均匀,风幕能够较好形成。2.模拟确定送风角度后,在该角度条件下,模拟不同风幕送风速度,对柜内温度场和速度场的影响,模拟选用送风速度分别为0.5m/s、0.8m/s、1.0m/s、1.2m/s,通过对比不同风速下柜内温度场的均匀性和稳定性,以及风幕的完整性,发现在送风速度为0.8m/s时柜内温度分布较为均匀,冷量溢出较少,风幕能够完好形成。3.进行试验测试,记录和处理数据,通过对比试验和数值模拟,能够发现试验和模拟偏差较小,验证了模拟的准确性,得出该送风角度和送风速度能够为冷藏柜优化设计提供依据。4.通过实验发现,冷藏柜内温度分布的均匀性和稳定性与柜内有无负载有较大影响,在柜内无载荷时,柜门开启状态下温度波动范围大,频率高,当放入商品载荷时,柜内温度波动较小,能够很好的稳定柜内温度场分布。
[Abstract]:In recent years, with the improvement of urbanization, the change of residents' lifestyle and the importance of food safety, the demand for intelligent refrigerators has increased significantly. In this paper, the temperature distribution and velocity distribution inside the refrigerated display cabinet are analyzed and studied. By establishing a mathematical calculation model to carry out numerical calculation, the optimum guidance and basis for the test are provided, and the better air curtain air delivery speed of the refrigerator is determined. The angle of the air curtain jet is tested at this angle and the velocity of the air supply to verify the accuracy of the simulation. First of all, the temperature distribution in the closed cabinet door of the freezer was tested, and further tests were carried out under the condition that the distribution in the cabinet was more stable and uniform. In this paper, the larger freezer with three cabinet doors was studied. A cabinet door was opened for experimental study and the internal temperature distribution of the test freezer was measured with an experimental instrument. Then the next step of the test is to place the food bags used for the test in the cabinet. The temperature field distribution in the freezer is measured under the condition of adding load in the test cabinet, and the temperature distribution in the cabinet is first measured when the cabinet door is closed. After the test is completed, the temperature distribution in the cabinet is measured when the door is opened. Finally, the experimental data are processed and compared with the numerical simulation results, and the following conclusions are drawn: 1. In the simulation, the temperature and velocity distribution in the tank under different jet angles are analyzed by comparing the air velocity of 1m/s with the non-isothermal fluid model. The simulated angle is 5 掳0 掳-5 掳-5 掳-10 掳. By comparing the four different air curtain jet angles, it is found that the angle of -5 掳inclination is the best, the difference of return air temperature is small, the temperature distribution in the cabinet is relatively uniform, and the air curtain can better form .2. After determining the air supply angle, under the condition of this angle, the influence of different air curtain supply velocity on the temperature field and velocity field in the cabinet is simulated. By comparing the uniformity and stability of the temperature field in the cabinet and the integrity of the air curtain under different wind speeds, it is found that the temperature distribution in the tank is more uniform and the cold overflow is less when the air supply speed is 0.8m/s, and the air supply velocity is 0.5m / s / s respectively 1.0 m / s / s ~ 1.2 m / s / s, respectively, by comparing the uniformity and stability of the temperature field in the cabinet under different wind speeds, as well as the integrity of the air curtain. The wind curtain can be formed perfectly. Test test, record and process data, through contrast test and numerical simulation, it can be found that the deviation between test and simulation is small, and the accuracy of simulation is verified. It is concluded that the air supply angle and the air supply speed can provide the basis for the optimum design of the freezer. It is found that the uniformity and stability of the temperature distribution in the freezer have great influence on the load or not. When there is no load in the cabinet, the temperature fluctuation range is large and the frequency is high in the open state of the cabinet door. When the load is put into the container, The temperature fluctuation in the cabinet is small, which can stabilize the temperature distribution in the cabinet.
【学位授予单位】：天津商业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB658

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