液氮制冷低温试验系统设计及优化  

Design and Optimization of Liquid Nitrogen Refrigeration Test System

作　　者：崔英伟[1,2] 雷霆 路梓照[1,2] 闫旭东 CUI Ying-wei;LEI Ting;LU Zi-zhao;YAN Xu-dong(Beijing Institute of Structure and Environment Engineering,Beijing 100076;Tianjin Aerospace Reliability Technology Co.,Ltd.,Tianjin 300462)

机构地区：[1]北京强度环境研究所,北京100076 [2]天津航天瑞莱科技有限公司,天津300462

出　　处：《环境技术》2021年第6期202-206,共5页Environmental Technology

摘　　要：本文叙述了一种利用液氮蒸发制冷的低温试验系统,该试验系统主要满足太阳能无人机碳纤维主梁的局部低温制冷需求。采用液氮流量调节阀进行控温时,由于低温加载区域热容较小,-90℃温控时会导致调节阀出现较大开关波动,温度波动较大。为满足温度控制精度的需求,对试验系统进了改进。改进后的试验系统采用两级控制,第一级闭环控制液氮调节阀开度,输出稳定的低温气体,第二级采用电加热器闭环调节气体温度,气体温度满足要求后通入试验空间。本文采用二级闭环控制的同时,优化了液氮制冷喷嘴,是的低温氮气均匀喷射至试验空间,确保了制冷空间的温度均匀度。In this paper,a low temperature test system using liquid nitrogen evaporation for refrigeration is described.This experimental system mainly meets the cooling test requirements of the carbon fiber main beam of the solar uav.In order to meet the requirement of temperature control accuracy,the test system adopts two-stage control.The first stage manually controls the liquid nitrogen flow,roughly controls the test temperature,and the second stage adopts the electric heater to precisely control the test temperature.The closed-loop controller of the electric heater is built with Compact-Rio hardware of NI company and fuzzy adaptive PID control program.Considering the uniformity of temperature in the test space,fluid analysis software ANSYS/Fluent was used to optimize the design of nitrogen nozzle to ensure the uniformity of cooling temperature.

关 键 词：液氮制冷 低温试验 Ansys-Workbench CFD 优化设计 

分 类 号：TH16[机械工程—机械制造及自动化] U467[机械工程—车辆工程]