The overall object of this paper is a systematic study of gaseous flows and thermal transport in twodimensional microand nano-channels using direct simulation Monte Carlo (DSMC) method. In the flow study, a validation of DSMC code was conducted by simulating a continuum flow in microchannel and the results show that the discrepancy of friction coefficient from theoretical prediction is well bel...

Frictional behavior of nano-undulated diamond-like carbon (DLC) films deposited by plasma assisted chemical vapor deposition (PACVD) process was investigated. In order to prepare the nano-undulated DLC film, a Si wafer with nano-sized Ni dots was prepared by rapid thermal annealing of Ni thin films. Since the structure of DLC film deposited by PACVD was independent of the substrate materials an...

Setose pads of aquatic Epeorus assimilis larvae are specialised structures located ventrally on the part of the gill lamella contacting the substrate and were suggested to have an attachment function in strong currents. In order to test the role of these setose pads in underwater attachment for the first time, we measured friction (shear) forces generated by the gill lamellae on solid substrate...

Friction and wear become significant at small scale lengths, particularly in MEMS/NEMS. Nanopatterns are regarded as a potential approach to solve these problems. In this paper, we investigated the friction behavior of nanopatterned silicon surfaces with a periodical rectangular groove array in dry and wear-less single-asperity contact at the nanoscale using molecular dynamics simulations. The ...

Lubricant and coolant can improve surface roughness in machining. In addition of ecological harms, thermal shock of coolant or lubricant may affect the surface integrity especially on surface residual stresses and micro-crack nucleation. Dry machining is ecologically desirable and it is considered as a necessity for manufacturing enterprises in the recent years. 55Cr3 steel grade is steel with ...

OBJECTIVE The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orthodontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodonti...

To demonstrate the influence of sliding friction of motion on a curve, a circular path is considered for simplicity on which a person slides from the highest point to the lowest point. A slide which represents a quadrant of radius 5 m and a person of mass 60 kg are considered for comparison in this paper. A Differential equation for motion considering the fact that the normal force depends both...

We investigate the effect of nanoscale variations in the surface roughness of individual particles on macroscale granular flow characteristics. Experiments were conducted in circular rotating tumblers with smooth and rough 2 and 3 mm steel particles. The smooth beads had a rms surface roughness of approximately 30 to 60 nm; rough beads had a surface roughness of approximately 240 to 350 nm. The...