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Abstract: The
nano-scale thin film lubrication of two kinds of lubricants, pure
tridecane and tridecane with polyhedral oligomeric silsesquioxanes
material T8H8 added (the mole fraction of T8H8 is 10%), at different
shear velocities are studied. Firstly, the interaction model of long
chain molecules is built. Then the average shear stresses, the
distribution of velocities, densities and temperatures of two kinds of
lubricates at four different shear velocities, 1 m/s, 5 m/s, 10 m/s, 20
m/s, are obtained by the molecular dynamics simulations. Some special
physical phenomena were investigated also. The results indicate that the
phenomena of delamination and slippage between layers appear at each
shear velocity of the two kinds of lubricants. These phenomena generally
occur in nano-scale thin film lubrication. Along with the unceasing
increase of the shear rate, the temperatures of the two kinds of
lubricants increase continuously. At each shear velocity, the central
layers of the two kinds of lubricates get the maximum temperatures
always. The results also show that the shear stresses and the
temperatures decreased observably after the T8H8 is added into the
tridecane. The T8H8 can greatly improve the lubrication effect of the
tridecane lubricant.
Key words: Tridecane
Polyhedral oligomeric silsesquioxanes Molecular dynamics simulation
Lubrication
CLC No: TH11712
国家自然科学基金(10472028)、黑龙江省科技厅国际合作(WC03112)和哈尔滨工业大学交叉学科基金(HIT.MD2002.05)资助项目.
Received 20050610, received in revised form 20060218
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