TY - JOUR
T1 - Numerical Study on Two-Dimensional Micro-Channel Flows Using the Gas-Kinetic Unified Algorithm
JO - Communications in Computational Physics
VL - 5
SP - 1393
EP - 1414
PY - 2018
DA - 2018/04
SN - 23
DO - http://doi.org/10.4208/cicp.OA-2016-0232
UR - https://global-sci.org/intro/article_detail/cicp/11220.html
KW - Micro-channel flow, Boltzmann model equation, gas molecular velocity distribution function, gas-kinetic unified algorithm, non-equilibrium rarefied effect of micro-scale flow.
AB - <p style="text-align: justify;">Based on the Boltzmann model equation, the Gas-Kinetic Unified Algorithm
(GKUA) will be developed to simulate the two-dimensional micro-scale gas flows with
irregular configuration. The numerical scheme for the direct evaluation of the unified
velocity distribution function in the computable model of the Boltzmann equation
and the multi-block grid docking technology are constructed, and the numerical
procedures of characteristic-based boundary conditions are presented to model
the gas-surface interaction and the inlet/outlet boundaries for the two-dimensional
micro-channel flows. The two-dimensional Couette flow, the pressure-driven micro-channel
flows, and the irregular micro-orifice flows in different scales are numerically
solved from high rarefied free-molecule to near-continuum flow with the Knudsen
numbers of $Kn$ = 100−0.01. The computed results are compared and validated with
the DSMC data in the transitional flow regime and the slip N-S solutions in the near-continuum
flow regime, in which the GKUA is verified accurately and smoothly to
simulate the two-dimensional micro-channel flows with strong adaptability and good
precision. The micro-channel flow features with the wide range of $Kn$ numbers in the
near-continuum slip and transitional flow regimes are revealed, and it is probable to
provide a way in developing a new numerical algorithm for micro-scale flows.</p>