万金庆,岳占凯,厉建国,王友君.马铃薯泥鼓风冷冻数值模拟与实验[J].农业机械学报,2017,48(4):298-304.
WAN Jinqing,YUE Zhankai,LI Jianguo,WANG Youjun.Numerical Analysis and Test on Characteristics of Temperature Decreasing of Mashed Potatoes[J].Transactions of the Chinese Society for Agricultural Machinery,2017,48(4):298-304.
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马铃薯泥鼓风冷冻数值模拟与实验   [下载全文]
Numerical Analysis and Test on Characteristics of Temperature Decreasing of Mashed Potatoes   [Download Pdf][in English]
投稿时间:2016-12-29  
DOI:10.6041/j.issn.1000-1298.2017.04.039
中文关键词:  马铃薯泥  鼓风  冷冻时间  降温特性  数值模拟
基金项目:国家高技术研究发展计划(863计划)项目(2012AA092301)
作者单位
万金庆 上海海洋大学 
岳占凯 上海海洋大学 
厉建国 上海海洋大学 
王友君 上海海洋大学 
中文摘要:为掌握马铃薯泥在鼓风冷冻过程中的温度变化规律,建立了短圆柱状马铃薯泥鼓风冷冻的三维数值模型,进行了三维非稳态数值模拟,并结合流场及不同时刻的温度场对马铃薯泥的冷冻过程进行了分析。实验验证表明该模型与实际情况吻合较好,冷冻时间相对误差为3.9%。以此为基础,研究了送风速度和温度对马铃薯泥冷冻过程的影响。结果表明,随着风速的提高,冷冻时间缩短,马铃薯泥内外温差增大,冷冻结束时马铃薯泥中心温度之间的差异先减小后增大。降低送风温度可以缩短冷冻时间,增大马铃薯泥中心温度之间的差异性和马铃薯泥内外温差。送风速度和温度对相变阶段的影响大于预冷段和深冷段。
WAN Jinqing  YUE Zhankai  LI Jianguo  WANG Youjun
Shanghai Ocean University,Shanghai Ocean University,Shanghai Ocean University and Shanghai Ocean University
Key Words:mashed potatoes  air blast  freezing time  characteristics of temperature decreasing  numerical simulation
Abstract:In order to investigate the characteristics of temperature decreasing of mashed potatoes without packages during freezing in an air blast freezer,a three-dimensional unsteady numerical model was established to simulate the freezing process of mashed potatoes. According to the thermo-physical properties of mashed potato, the process of the temperature decreasing during freezing was simulated by Fluent,after which the airflow information in the container was obtained.A test was done to verify the accuracy of the model,and it was found that the simulation values and test values were in good agreement,the maximum temperature difference between the test data and simulation result was 7.1K and the relative error of freezing time was 3.9%. After that,two design parameters (air velocity and air temperature) which would affect the freezing process were analyzed.Improving the air velocity can shorten the time of freezing but would improve the maximum temperature difference between the mashed potato’s core and edge. The variation coefficient of temperature among mashed potatoes was firstly increased and then decreased with the increase of air velocity, and it was minimum when the air velocity was 6m/s. When the air velocity was bigger than 6m/s,the freezing rate trended to be steady along with the growing of air velocity. Reducing the air temperature can effectively improve the temperature decreasing of mashed potatoes during freezing but also would improve the variation coefficient of temperature among mashed potatoes. The results reviewed some characteristics of the freezing of mashed potatoes without packages in an air blast freezer, which can provide a reference value for the optimization of the equipments and technologies for the freezing of foodstuffs.

Transactions of the Chinese Society for Agriculture Machinery (CSAM), in charged of China Association for Science and Technology (CAST), sponsored by CSAM and Chinese Academy of Agricultural Mechanization Science(CAAMS), started publication in 1957. It is the earliest interdisciplinary journal in Chinese which combines agricultural and engineering. It always closely grasps the development direction of agriculture engineering disciplines and the published papers represent the highest academic level of agriculture engineering in China. Currently, nearly 8,000 papers have been already published. There are around 3,000 papers contributed to the journal each year, but only around 600 of them will be accepted. Transactions of CSAM focuses on a wide range of agricultural machinery, irrigation, electronics, robotics, agro-products engineering, biological energy, agricultural structures and environment and more. Subjects in Transactions of the CSAM have been embodied by many internationally well-known index systems, such as: EI Compendex, CA, CSA, etc.

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