基于多体动力学仿真的冰箱助吸器优化设计

某款冰箱在关门过程中,门体在多个小角度处出现悬停的现象,影响用户的体验。针对这一问题,基于多体动力学仿真对冰箱助吸器进行了优化设计。将助吸器变形量、刚度、有效力臂接触位置点至铰链轴心连线长度,以及这一连线与接触位置法向夹角作为关键因子,研究关键因子与设计目标之间的关系,进行助吸器的结构设计与性能评估。在此基础上,基于多体动力学仿真,实现助吸器的优化,并形成最终设计方案。基于多体动力学仿真进行优化设计,可以缩短开发周期,提高设计效率,具有较高的实用价值。     

冷冻机油对R600a型冰箱压缩机制冷性能的影响

采用GB 9098-1996压缩机制冷性能评定方法,对不同类型、不同黏度等级冷冻机油与R600a型冰箱压缩机制冷性能之间的关系进行分析.结果表明:适宜的低黏度型冷冻机油有助于提高R600a型冰箱压缩机的制冷性能;制冷量与制冷系数随冷冻机油黏度变化趋势曲线的交叉点处为压缩机发挥最佳制冷性能的控制点;冷冻机油对R600a型...     

Experimental investigation of vortex tube refrigerator with a divergent hot tube

Energy separation performance of vortex tube can be improved by using a divergent hot tube. Experiments are carried out to investigate the influence of the geometrical parameters on vortex tube refrigeration capacity by using nitrogen as the working fluid. In this work, the parameters are focused on the divergence angle of hot tube, length of divergent hot tube and number of nozzle intakes. Experimental results present that there is an optimum angle for obtaining the highest refrigeration performance, and 4° is the optimal candidate under our experimental conditions. Divergent tube length which exceeds a critical length has slight effect on the refrigeration capacity. The critical length to diameter ratio is L/D = 12 in our experiment. Increasing number of nozzle intakes increases the sensitivity of temperature reduction and can obtain the highest possible temperature reduction. Moreover, similarity relations for the prediction of the cold exit stream are presented and confirmed by the experimental data.     

磁制冷器

磁制冷是一种以磁热效应为基础的制冷方法.最早是由德国物理学家于1880年发现。早期用于制取极低的温度。近年来,室温磁制冷取得了较大的突破,已经研制出适合家用的磁制冷冰箱,同时由于它的制冷系数高和对大气的全球气候变暖影响小等优点,将成为一种很有发展前途的制冷方式。本文论述磁制冷和磁制冷冰箱的基本原理。     

浅谈低温冷库螺杆配组双级氟制冷系统调试技术

本文以“复盛”中低温螺杆配组双级（PLC控制、蒸发式冷凝器）为例,结合多年调试氟制冷系统的工作经验,简述一下低温冷库螺杆配组双级氟制冷系统的调试技术。     

SIMULATION AND EXPERIMENTAL STUDY ON THE AIR FLOW AND HEAT LOADS OF DIFFERENT REFRIGERATOR CABINET DESIGNS

As the economy has been growing in the past decade, consumers in Taiwan start to consider how to raise living quality. As people tend to adopt the westerners' living style of purchasing food once every week or two weeks. Large grocery stores, hence, have been built both in urban and suburban areas. This change results in a growing need of better-designed refrigerator-freezers (RFs). Consequently, consumers need RF models with better or more cooling functions, larger volumetric capacity, and efficient energy use

A 1997 top-mount refrigerator with a volume of about 460 liters was selected as the baseline model. This study used computer aided finite element methods (FEM) to analyse and establish designs for RFs. These designs included different insulation properties and various cool air flow rates and outlets in the freezer and fresh food compartments. The following outcomes were investigated in the simulating work:

•The thermal responses of the insulation material on RF cabinets

•The effect of a modified cool air outlet on the air flow distribution and heat loads

The simulation results were then compared with experimental data. Agreement was found between simulation and experimental results. This suggested that computer-aided simulation could serve as a reliable tool for other designs similar to cases practiced in this RF study.     

小型液氮设备产量降低的故障分析和排除

KLN-20Y型小型液氮设备因为制冷机蓄冷器带有水蒸气,换热效率下降,液氮产量降低。详细介绍故障现象和原因分析过程,阐述故障处理和预防措施。     

Pulse tube stirling machine with warm gas-driven displacer

A pulse tube type stirling machine with warm gas-driven displacer which has a displacer rod is discussed with numerical simulation when it is used as a cryogenic refrigerator, room temperature refrigerator and engine. It has both the advantages of gas-driven-stirling machine with high efficiency and simplicity and the advantages of pulse tube machine with no moving parts at low temperatures. A nodal analysis method that includes the linear motor and the displacer in the machine is introduced. Numerical results show that it has high potential to be used as the cryogenic refrigerator, room temperature refrigerator and engine. In this type of machine, there is an optimum phase angle between displacer and piston, and an optimum swept volume ratio of displacer over compressor for efficiency. The phase angle and swept volume ratio can be adjusted by the natural frequency of the displacer and the diameter of the displacer rod when it is used as a refrigerator.