Fig.1

Schematic diagrams of plane Couette flow， plane Poiseuille flow， and Rayleigh-Bénard flow

Fig.2

Streamwise velocity profiles of Poiseuille flow at different Kn （ax =5×10-5）

Fig.3

Streamwise velocity profiles of Poiseuille flow at different χ （ax =5×10-5， Kn=0.02）

Fig.4

Streamwise velocity profiles of Poiseuille flow at different ax （Kn=0.01）

Fig.5

Streamwise velocity profiles of Couette flow （The upper and lower plates move in the opposite direction at a speed of Ma=0.1） at different Kn

Fig. 6

Streamwise velocity profiles of Couette flow （The upper and lower plates move in the opposite direction at a speed of Ma=0.1） at different χ （Kn=0.02）

Fig.7

Streamwise velocity profiles of Couette flow at different plate moving speeds （Kn=0.02）

Fig.8

Density and temperature profiles of Rayleigh-Bénard flow corresponding to HS and VHS models （Kn=0.01）

Table 1

Eigenvalues of the least stable mode of Poiseuille flow （Ma=5×10-4， Re=2 000.0， α=1.0）

Table 2

Eigenvalues of the least stable mode of Couette flow （Ma=5×10-4， Re=800.0， α=1.0）

Fig.9

Phase velocity spectra

Table 3

Eigenvalues of the least stable mode of Couette flow （Ma=0.1， Kn=0.04， α=3.0）

Table 4

Eigenvalues of the least stable mode of Poiseuille flow （ax =0.002， Kn=0.01， α=3.0）

Fig.10

Neutral curves in （Fr， Kn） plane for HS monatomic gas （Kn=0.01）

Fig.11

Phase velocity and growth rate of the least stable mode of Poiseuille flow driven by ax =5×10-5 versus α at different Kn

Fig.12

Phase velocity and growth rate of the least stable mode of Poiseuille flow driven by ax =5×10-5 versus Knudsen number at different wave numbers

Fig.13

Phase velocity and growth rate of the least stable mode of Poiseuille flow versus α at different χ （Kn=0.03， ax =5×10-5）

Fig.14

Phase velocity and growth rate of the least stable mode of Poiseuille flow versus α at different ax （Kn=0.01）

Fig.15

Phase velocity and growth rate of the least stable mode of Couette flow versus α at different Kn （Ma=0.01）

Fig.16

Phase velocity and growth rate of the least stable mode of Couette flow versus Kn at different α （Ma=0.01）

Fig.17

Phase velocity and growth rate of the least stable mode of Couette flow versus α at different χ （Kn=0.03， Ma=0.1）

Fig.18

Phase velocity and growth rate of the least stable mode of the Couette flow versus α at different Ma （χ=1.0， Kn=0.02）

Fig.19

The neutral curves of monoatomic and diatomic gases for different molecular models （α=π）

Fig.20

Growth rate of the most unstable mode varying with Fr and Kn for different molecular models （α=π）

Fig.21

Growth rates of the most unstable modes corresponding to diatomic gases under different molecular models varying with α （Fr=3.0， Kn=0.01）

Fig.22

Phase velocity spectra at different Kn （Fr=3.0， α=π）

Fig.23

Variation of growth rate of the most unstable mode with α for different Kn （Fr=3.0）

Table 5

Grid convergence analysis of growth rate corresponding to the least stable mode of Rayleigh-Bénard flow