盒式气调包装机气体置换结构内部3-D流场的模拟

Simulation Analysis of 3-D Flow Field within Gas Replacement Devices of Modified Atmosphere Packaging Machine with Trays

气体置换装置是气调包装机的核心部件。以盒式气调包装机中2种典型气体置换装置结构为研究对象,建立了2种气体置换结构的物理模型和包装盒内气体流场分析数学模型,应用Fluent软件对包装盒内的气体流场进行三维数值模拟。建立了保证气体置换质量的包装盒内三维流场评价指标,分析了气体置换装置充、排气孔的结构布置与排列方式对气体置换性能的影响。结果表明,与传统结构相比,新设计结构在气体置换率、流场静压分布、气体平均流速以及耗气量等方面均具有更佳的性能。

The gas replacement device is the key part of the modified atmosphere packaging machine. The structures of two typical kinds of gas replacement devices with trays were analyzed. The mathematical model of 3-D turbulent gas flow field within the tray was proposed, and then the numerical simulation of the gas-flow field was conducted by means of the Fluent software. The distributions of the flow field within trays for two kinds of gas replacement devices were obtained. The evaluation indexes of the flow field for ensuring the quality of gas replacement within tray were established. Effect of the arrangement mode of gas inlet and outlet on properties of gas replacement was analyzed. The results show that, compared to the typical traditional structure, the new gas replacement devices has better performance in replacement ratio of gas, static pressure distribution, average velocity of flow, and gas consumption.