液氮内喷式刀柄温度场仿真分析
2018-12-20
作者：李宽，刘海波，刘阔，韩灵生，王晋宇，王永青
单位：大连理工大学
摘要：为实现难加工材料的液氮内喷式铣削加工，分析了液氮内喷式铣刀刀柄在强冷却条件下的设计要求。基于对刀柄实际工况下的传热分析，并利用计算CFD流体力学FLUENT分析软件，模拟了转速3500r/min、液氮流量50L/h工况下刀柄的稳态温度场分布。针对轴承和刀柄锥面等关键部位受液氮冷源影响而失效的问题，提出了在流道内壁面覆盖改性PTFE聚四氟乙烯隔热层的方案。对比有无隔热层结构对刀柄温度场的影响，分析了刀柄温度场随隔热层厚度的变化规律。模拟结果表明，当隔热层为2mm时，可满足刀柄的隔热性能要求。
关键词：液氮；内喷式刀柄；温度场；热仿真
中图分类号：TG506.3；TH161文献标志码：A
Temperature Field Simulation of Liquid Nitrogen Jet Cooling Tool Holder
Li Kuan，Liu Haibo，Liu Kuo，Han Lingsheng，Wang Jinyu，Wang Yongqing
Abstract:To accomplish the cryogenic jet cooling methodfor difficulttomachine materials milling，the design requirements of the liquid nitrogen jet cooling tool holder for milling under strong cooling conditions are analyzed.Based on the heat transfer analysis of the tool holder in operation condition，the temperature field of the tool holder is analyzed by CFD software FLUENT under rotational speed of 3500r/min and liquid nitrogen flow rate of 50L/h.To avoid bearing and the tool holder taper interface destroyed by cryogenic temperature，a heat insulating layer made by modified PTFE is proposed.The influence of the insulation layer on the temperature field of the tool holder is simulated，and the rule of the temperature changed along with the thickness of insulation is analyzed，thesimulation results showed thatthe heat insulation performance is satisfied when the insulation thickness is 2mm.
Keywords:liquid nitrogen；jet cooling tool holder；temperature field；thermal simulation