Development of an axisymmetric, turbulent and unstructured navier-stokes solver

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2010

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Akdemir, Mustafa

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An axisymmetric, Navier-Stokes finite volume flow solver, which uses Harten, Lax and van Leer (HLL) and Harten, Lax and van Leer–Contact (HLLC) upwind flux differencing scheme for spatial and uses Runge-Kutta explicit multi-stage time stepping scheme for temporal discretization on unstructured meshe is developed. Developed solver can solve the compressible axisymmetric flow. The spatial accuracy of the solver can be first or second order accurate. Second order accuracy is achieved by piecewise linear reconstruction. Gradients of flow variables required for piecewise linear reconstruction are calculated by Green-Gauss theorem. Baldwin-Lomax turbulent model is used to compute the turbulent viscosity. Approximate Riemann solver of HLL and HLLC implemented in solver are validated by solving a cylindrical explosion case. Also the solver’s capability of solving unstructured, multi-zone domain is investigated by this problem. First and second order results of solver are compared by solving the flow over a circular bump. Axisymmetric flow in solid propellant rocket motor is solved in order to validate the axisymmetric feature of solver. Laminar flow over flat plate is solved for viscous terms validation. Turbulent model is studied in the flow over flat plate and flow with mass injection test cases.

Subject Keywords

Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12611904/index.pdf
https://hdl.handle.net/11511/19589

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Akdemir, “Development of an axisymmetric, turbulent and unstructured navier-stokes solver,” M.S. - Master of Science, Middle East Technical University, 2010.