【摘要】 为解决生物样本的深冷低温存储问题,本文设计了一种利用液氮制冷的深冷低温箱,并对低温箱的制冷性能进行研究。采用Fluent软件模拟与实验相结合的方法,模拟低温箱中换热器自然对流换热过程,研究了LN₂深冷低温冷藏箱的制冷性能,对自然对流换热时间、低温箱中的气流流动规律以及LN₂的消耗量进行预测,结合模拟结果,对低温箱的制冷性能展开实验研究,并将实验数据与模拟数据进行对比。研究结果表明,由于涡流作用,箱体前部温度均匀性优于后部,箱内最大气体流速0.24m/s,低温箱内平均温度从初始温度288.15K下降到123K,耗时264min,平均制冷量1434.09kW,该过程消耗LN₂质量为110.94kg,模拟时间误差16.3%,LN₂质量误差15.7%。该研究为LN₂深低温冷藏箱的设计提供了理论依据,具有一定的应用价值。更多还原

【Abstract】 In order to solve the cryogenic storage problem of biological samples,a cryogenic chamber using liquid nitrogen refrigeration is designed in this paper,and the refrigeration performance of the cryogenic chamber is studied.Using the Fluent software to simulate software combined with practice,the method of simulation of cold box process of natural convection heat transfer in heat exchanger,it studied the LN₂ cryogenic cooling performance of the cooler at low temperature,and predicts natural convection heat exchange time,the air flow pattern in the box and the consumption of liquid nitrogen.Combined with the simulation result,it studies the cooling performance of low temperature experiment research box,and compares the experimental data and simulation data.The maximum gas velocity was 0.24 m/s.The average temperature in the cryogenic chamber decreased from the initial temperature of 288.15 Kto 123 K.It took 264 min and the average cooling capacity was 1434.09 kW.The process consumed 110.94 kg liquid nitrogen.This study provides a theoretical basis for the design of LN₂ deep and low temperature refrigerator,which has certain application value.更多还原