Lattice Boltzmann simulation of surface roughness effect on gaseous flow in a microchannel

2008 ◽  
Vol 104 (1) ◽  
pp. 014902 ◽  
Author(s):  
Zhenhua Chai ◽  
Zhaoli Guo ◽  
Lin Zheng ◽  
Baochang Shi
Keyword(s):  
Surface Roughness ◽  
Lattice Boltzmann ◽  
Roughness Effect ◽  
Gaseous Flow ◽  
Lattice Boltzmann Simulation

ROUGHNESS EFFECT OF DIFFERENT GEOMETRIES ON MICRO GAS FLOWS BY LATTICE BOLTZMANN SIMULATION

2009 ◽  
Vol 20 (06) ◽  
pp. 953-966 ◽  
Author(s):  
CHAOFENG LIU ◽  
YUSHAN NI ◽  
YONG RAO
Keyword(s):  
Surface Roughness ◽  
Lattice Boltzmann ◽  
Experimental Studies ◽  
Resistance Coefficient ◽  
Lattice Boltzmann Model ◽  
Gas Flows ◽  
Fractal Boundary ◽  
Roughness Effects ◽  
Roughness Effect ◽  
Relative Roughness

The roughness effects of the gas flows of nitrogen and helium in microchannels with various relative roughnesses and different geometries are studied and analyzed by a lattice Boltzmann model. The shape of surface roughness is simulated to be square, sinusoidal, triangular, and fractal. Numerical computations compared with theoretical and experimental studies show that the roughness geometry is an important factor besides the relative roughness in the study of the effects of surface roughness. The fractal boundary presents a higher influence on the velocity field and the resistance coefficient than other regular boundaries at the same Knudsen number and relative roughness. In addition, the effects of rarefaction, compressibility, and roughness are strongly coupled, and the roughness effect should not be ignored in studying rarefaction and compressibility of the microchannel as the relative roughness increases.

Lattice Boltzmann Simulation of Micro Poiseuille Flow in Curved Rough Channels

2009 ◽  
Author(s):  
Weizhong Li ◽  
Wenning Zhou
Keyword(s):  
Lattice Boltzmann ◽  
Specular Reflection ◽  
Lattice Boltzmann Model ◽  
Solid Boundary ◽  
Gas Flows ◽  
Curved Channel ◽  
Roughness Effect ◽  
Lattice Boltzmann Simulation ◽  
Boltzmann Model ◽  
Bounce Back

This paper studies the roughness effect of the two-dimensional micro Poiseuille gas flows in a curved channel by a modified lattice Boltzmann model. A method relating to the Knudsen number (Kn) with the relaxation time is discussed. In addition, to capture the slip velocity on a solid boundary more accurately, a combined boundary scheme (CBC), which combines the no-slip bounce-back and the free-slip specular reflection schemes, is applied to boundary condition treatment. The rough wall of the micro-channel is described by uniformly distributed rectangular or triangular rough elements. The simulation results show that the roughness and the geometries of the channel have great effects not only on velocity distribution but also on pressure distribution.

Lattice Boltzmann Simulation of Gaseous Flow in Microchannel With Rectangular Grooves

2010 ◽  
Author(s):  
Zahra Hashemi ◽  
Omid Abouali ◽  
Reza Kamali
Keyword(s):  
Lattice Boltzmann ◽  
Gas Flow ◽  
Rarefied Gas ◽  
Flow Characteristics ◽  
Heat Removal ◽  
Computer Code ◽  
Constant Wall Temperature ◽  
Gaseous Flow ◽  
Lattice Boltzmann Simulation ◽  
Boltzmann Method

This paper presents a numerical investigation based on the Lattice Boltzmann method for gaseous flow in a microchannel with rectangular grooves on the walls. Firstly, the prepared computer code is validated with comparison the obtained results with analytic solution for fully developed rarefied gas flow in a simple micro channel. The effects of the rectangular grooves on the flow characteristics and heat transfer behavior are discussed and the results are compared with a simple mircochannel. For this purpose, a two-dimensional constant wall temperature microchannel with air as the coolant is investigated. The results show that the heat removal increases for the grooved channel more than 50% compared with a simple microchannel. But the pressure drop is also increases due to the effects of grooves. The increase in friction factor is more than twice for some Knudsen numbers.

scholarly journals Surface roughness effect on a droplet impacting a thin film using pseudo-potential lattice Boltzmann method

AIP Advances ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 085312
Author(s):  
Jiayu Zhou ◽  
Hao Yuan ◽  
Xiaolong He ◽  
Dianguang Ma ◽  
Chunhang Xie ◽  
...  
Keyword(s):  
Thin Film ◽  
Surface Roughness ◽  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Roughness Effect ◽  
Boltzmann Method ◽  
Pseudo Potential
Sign in / Sign up

Export Citation Format

Share Document