航空发动机后轴承腔内壁与滑油的换热分析是轴承腔热防护结构设计的基础。对航空发动机轴承腔内壁换热模拟试验件开展试验与数值模拟研究,得到了滑油油膜对轴承腔内壁的换热影响。通过测量试验件外壁面、内壁面以及滑油油膜的温度得到...航空发动机后轴承腔内壁与滑油的换热分析是轴承腔热防护结构设计的基础。对航空发动机轴承腔内壁换热模拟试验件开展试验与数值模拟研究,得到了滑油油膜对轴承腔内壁的换热影响。通过测量试验件外壁面、内壁面以及滑油油膜的温度得到了试验件内壁面换热热流密度与换热系数的分布;结合CLSVOF(Coupled Level Set and Volume Of Fluid)油/气两相流以及热-流-固耦合计算方法对试验件进行了换热分析,并将内壁对滑油的局部热流量的计算结果与试验结果进行了对比,结果显示两者在各个工况下均吻合较好。通过将局部换热系数计算值与当地的滑油流动雷诺数Rel进行对比分析,结果显示内壁局部努赛尔数Nuw与Rel的0.7次方成正比关系。另外,对转速对换热的影响进行分析得到Nuw与旋转雷诺数Re_(rot)的0.345次方呈正比关系。展开更多
Seven kinds of used mineral lubricating oils,including hydraulic oils,film bearing oils,steam turbine oil and gear oils,were recycled by reclamation and adding additives.Physical and chemical properties of the recycle...Seven kinds of used mineral lubricating oils,including hydraulic oils,film bearing oils,steam turbine oil and gear oils,were recycled by reclamation and adding additives.Physical and chemical properties of the recycled oils were measured and their lubrication performances were evaluated by the original and modified four-ball testers.Worn surfaces were analyzed by energy dispersive X-ray spectroscopy and Raman microscope.The recycling costs of burning,re-refined and refortified were estimated.Results showed that physical and chemical properties of the refortified oils were improved effectively and became in the industrial access standard.With the different friction materials under different loads,refortified oils provided excellent lubrication performances,much better than those of fresh oils.Because of additives replenished,the different lubrication films could form on the worn surfaces.A rough financial calculation revealed that the refortification process could produce the most economic value among the three methods.展开更多
文摘航空发动机后轴承腔内壁与滑油的换热分析是轴承腔热防护结构设计的基础。对航空发动机轴承腔内壁换热模拟试验件开展试验与数值模拟研究,得到了滑油油膜对轴承腔内壁的换热影响。通过测量试验件外壁面、内壁面以及滑油油膜的温度得到了试验件内壁面换热热流密度与换热系数的分布;结合CLSVOF(Coupled Level Set and Volume Of Fluid)油/气两相流以及热-流-固耦合计算方法对试验件进行了换热分析,并将内壁对滑油的局部热流量的计算结果与试验结果进行了对比,结果显示两者在各个工况下均吻合较好。通过将局部换热系数计算值与当地的滑油流动雷诺数Rel进行对比分析,结果显示内壁局部努赛尔数Nuw与Rel的0.7次方成正比关系。另外,对转速对换热的影响进行分析得到Nuw与旋转雷诺数Re_(rot)的0.345次方呈正比关系。
基金supported by the National Basic Research Program("973" Project)(Grant No.2013CB632303)the Scientific Research Plan of Hubei Education Department(Grant NO.Q20131707)
文摘Seven kinds of used mineral lubricating oils,including hydraulic oils,film bearing oils,steam turbine oil and gear oils,were recycled by reclamation and adding additives.Physical and chemical properties of the recycled oils were measured and their lubrication performances were evaluated by the original and modified four-ball testers.Worn surfaces were analyzed by energy dispersive X-ray spectroscopy and Raman microscope.The recycling costs of burning,re-refined and refortified were estimated.Results showed that physical and chemical properties of the refortified oils were improved effectively and became in the industrial access standard.With the different friction materials under different loads,refortified oils provided excellent lubrication performances,much better than those of fresh oils.Because of additives replenished,the different lubrication films could form on the worn surfaces.A rough financial calculation revealed that the refortification process could produce the most economic value among the three methods.
