北京航空航天大学学报
北京航空航天大學學報
북경항공항천대학학보
2001年
1期
88-92
,共5页
铁磁流体%润滑%屈服%剪切稀化%粘附核
鐵磁流體%潤滑%屈服%剪切稀化%粘附覈
철자류체%윤활%굴복%전절희화%점부핵
利用外加磁场可以直接调节铁磁流体润滑膜的承载能力,因为在外磁场中铁磁流体的粘度增大. 实验研究表明,铁磁流体是一种非牛顿流体,它同时表现出Bingham塑性体和拟塑性体的特性. 铁磁流体的非牛顿流体行为受外磁场强度和方向的影响. 铁磁流体的本构方程可以表示为τ(H,D)=τs(H)+η1(H)D+η2(H)D2.由于铁磁流体具有屈服剪应力τs(H),而可能出现“固态”核粘附于轴承表面上.铁磁流体的拟塑性体行为对核的生成条件有影响.在铁磁流体润滑的轴承中,纯剪切流截面C0不同于普通Bingham塑性体润滑的轴承.作为一个实际的例子而给出铁磁流体润滑平板滑块的承载能力和摩擦力的解.
利用外加磁場可以直接調節鐵磁流體潤滑膜的承載能力,因為在外磁場中鐵磁流體的粘度增大. 實驗研究錶明,鐵磁流體是一種非牛頓流體,它同時錶現齣Bingham塑性體和擬塑性體的特性. 鐵磁流體的非牛頓流體行為受外磁場彊度和方嚮的影響. 鐵磁流體的本構方程可以錶示為τ(H,D)=τs(H)+η1(H)D+η2(H)D2.由于鐵磁流體具有屈服剪應力τs(H),而可能齣現“固態”覈粘附于軸承錶麵上.鐵磁流體的擬塑性體行為對覈的生成條件有影響.在鐵磁流體潤滑的軸承中,純剪切流截麵C0不同于普通Bingham塑性體潤滑的軸承.作為一箇實際的例子而給齣鐵磁流體潤滑平闆滑塊的承載能力和摩抆力的解.
이용외가자장가이직접조절철자류체윤활막적승재능력,인위재외자장중철자류체적점도증대. 실험연구표명,철자류체시일충비우돈류체,타동시표현출Bingham소성체화의소성체적특성. 철자류체적비우돈류체행위수외자장강도화방향적영향. 철자류체적본구방정가이표시위τ(H,D)=τs(H)+η1(H)D+η2(H)D2.유우철자류체구유굴복전응력τs(H),이가능출현“고태”핵점부우축승표면상.철자류체적의소성체행위대핵적생성조건유영향.재철자류체윤활적축승중,순전절류절면C0불동우보통Bingham소성체윤활적축승.작위일개실제적례자이급출철자류체윤활평판활괴적승재능력화마찰력적해.
The load carrying capacity of the ferrofluid lubricating films can be controlled directly by means of the applied magnetic field, since the viscosity of the ferrofluid increases in the case of magnetic field. The experimental investigations showed that the ferrofluid is an non-Newtonian fluid: it behaves simultaneously as a Binghamoplastic and as a pseudoplastic. The non-Newtonian behavior of the ferrofluid is dependent both on oreintation and on intensity of the applied magnetic field. The constitutive equation of the ferrofluid can be expressed as τ(H,D)=τs(H)+η1(H)D+η2(H)D2. It is possible that the “solid” cores appear and adhere to the surfaces of bearing, since the ferrofluid has a yield shear stress τs(H). The pseudoplastic behaviors of the ferrofluid have an effect on the condition for core occurrence. The cross section C0 of a pure Couette flow in the ferrofluid lubricated bearing is different from that in the ordinary Binghamoplastic lubricated bearing. The solutions of load carrying capacity and friction force of plane slider lubricated with ferrofluid are given as an actual example.