Practical Aspects of Computational Fluid Dynamics for Turbomachinery
Abstract
The following dissertation examines several aspects of numerical simulations for turbomachinery flows modeled with an in-house Reynolds-averaged Navier-Stokes solver. The impact of the turbulence model on the solution is also explored in this work. Additionally, the effects of different solution limiters, including both a new and modified limiter, are examined.
This dissertation also presents a new grid generator that was tailored for turbomachinery geometries. The grid generator uses a combination of structured grid blocks to discretize a single blade passage domain. Structured grid blocks can also be placed at the blade tip, allowing for the modelling of tip leakage flows.
A number of canonical cases were used to validate the additions and modifications to the flow solver. Among these cases were the inviscid flow through a convergent-divergent nozzle and a turbulent flat plate. It is shown that the new and modified limiters perform similarly to the existing limiter functions, and in some cases, out-perform their predecessors.
The flow solver is further validated against two turbomachinery cases: an annular turbine vane and a transonic fan. Comparisons with experimental data are made in both cases. The effects of turbulent inlet conditions and the under-relaxation of the turbulence equations are examined for the turbine vane geometry. Two novel rubbing configurations are presented and examined in the turbulent transonic fan case. Additionally, a transonic fan case, which includes the tip leakage flow, is also presented and compared against the rubbing cases.
Citation
Carpenter IV, Forrest Lafon (2016). Practical Aspects of Computational Fluid Dynamics for Turbomachinery. Doctoral dissertation, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /158055.