scholarly journals Optimal shape control of airfoil in compressible gas flow governed by Navier-Stokes equations

2013 ◽  
Vol 2 (3) ◽  
pp. 495-516 ◽  
Author(s):  
Jan Sokolowski ◽  
Pavel Plotnikov
Keyword(s):  
Shape Control ◽  
Gas Flow ◽  
Stokes Equations ◽  
Optimal Shape ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Optimal Shape Control ◽  
Compressible Gas Flow ◽  
Compressible Gas

Gas flows in microchannels and microtubes

2007 ◽  
Vol 589 ◽  
pp. 305-314 ◽  
Author(s):  
CHUNPEI CAI ◽  
QUANHUA SUN ◽  
IAIN D. BOYD
Keyword(s):  
Compressible Flows ◽  
Gas Flow ◽  
Stokes Equations ◽  
Natural Extension ◽  
Velocity Slip ◽  
Navier Stokes ◽  
Gas Flows ◽  
Wall Boundary Conditions ◽  
Compressible Gas Flow ◽  
Compressible Gas

This study analyses compressible gas flows through microchannels or microtubes, and develops two complete sets of asymptotic solutions. It is a natural extension of the previous work by Arkilicet al. on compressible flows through microchannels. First, by comparing the magnitudes of different forces in the compressible gas flow, we obtain proper estimations for the Reynolds and Mach numbers at the outlets. Second, based on these estimations, we obtain asymptotic analytical solutions of velocities, pressure and temperature distributions of compressible gas flow inside the microchannels and microtubes with a relaxation of the isothermal assumption, which was previously used in many studies. Numerical simulations of compressible flows through a microchannel and a microtube are performed by solving the compressible Navier–Stokes equations, with velocity slip and temperature jump wall boundary conditions. The numerical simulation results validate the analytical results from this study.

TRIGGERING OF DETONATION PROCESSES IN PROPULSION CHAMBER

2021 ◽  
Vol 14 (2) ◽  
pp. 40-45
Author(s):  
D. V. VORONIN ◽  
Keyword(s):  
Thermal Conductivity ◽  
Numerical Modeling ◽  
Gas Flow ◽  
Stokes Equations ◽  
Navier Stokes ◽  
Two Dimensional ◽  
Navier Stokes Equations ◽  
Chemically Reacting ◽  
Plane Disk ◽  
And Diffusion

The Navier-Stokes equations have been used for numerical modeling of chemically reacting gas flow in the propulsion chamber. The chamber represents an axially symmetrical plane disk. Fuel and oxidant were fed into the chamber separately at some angle to the inflow surface and not parallel one to another to ensure better mixing of species. The model is based on conservation laws of mass, momentum, and energy for nonsteady two-dimensional compressible gas flow in the case of axial symmetry. The processes of viscosity, thermal conductivity, turbulence, and diffusion of species have been taken into account. The possibility of detonation mode of combustion of the mixture in the chamber was numerically demonstrated. The detonation triggering depends on the values of angles between fuel and oxidizer jets. This type of the propulsion chamber is effective because of the absence of stagnation zones and good mixing of species before burning.

Dynamical Study of a Molten Boundary Layer Ejected by Laminar Gas Flow

2014 ◽  
Vol 348 ◽  
pp. 88-93 ◽  
Author(s):  
S. Aggoune ◽  
El Hachemi Amara
Keyword(s):  
Boundary Layer ◽  
Shear Stress ◽  
Gas Flow ◽  
Stokes Equations ◽  
Gas Jet ◽  
Navier Stokes ◽  
Dynamical Study ◽  
Navier Stokes Equations ◽  
Finite Differences Method ◽  
Layer Increase

We consider in the present work the fusion laser cutting of stainless steel sheets under a nitrogen laminar gas jet. The molten metal is treated as a laminar and steady viscous incompressible fluid. The mathematical model describing our problem is set in terms of Navier-Stokes equations, solved numerically using the finite differences method, where the effect of the gas jet velocity on the molten boundary layer is considered. The generated shear stress occurring on the gas-liquid interface and its contribution in the momentum is carried out, and it is found that when the skin friction and the shear stress decrease, the thickness and the velocity at the edge of the molten boundary layer increase along the kerf surface. The layer thickness reduces when the assisting gas velocity is increased.

Sign in / Sign up

Export Citation Format

Share Document