Large eddy simulation of high pressure turbine cascade
Abstract/Contents
- Abstract
- In gas turbine engine design, better efficiency is achieved through higher turbine inlet temperature. As a result, the nozzle guide vanes and rotor blades of a High Pressure Turbine (HPT) are subject to an increasingly hostile thermal environment. High levels of turbulence and hot streaks from the upstream combustor impinge on the HPT blade rows. Heat transfer prediction of the thermally critical regions of a HPT is a vital element in the design of gas turbine engines. The effect of inlet turbulence on heat transfer and boundary layer development on a HPT vane cascade has been studied numerically using a high-order overset Large Eddy Simulation procedure. Numerical visualizations of instantaneous boundary layer flow show presence of long, meandering, streamwise oriented streaky structures on both the suction and pressure sides of the blade. Stretching of vortices from the inlet turbulence around the leading edge and subsequent transport of them into the blade passage produces these boundary layer streaks. Significant enhancement in laminar heat transfer, especially around the leading edge and on the pressure side is observed due to these structures. Backward jets are created in the fluctuation velocity field in the boundary layer, which interact with eddies in the turbine passage leading to bypass transition of the suction surface boundary layer. Simulations with organized spanwise disturbance show sensitivity of leading edge region heat transfer to the intensity and length scale of the inlet disturbance.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2010 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | Bhaskaran, Rathakrishnan |
|---|---|
| Associated with | Stanford University, Department of Mechanical Engineering |
| Primary advisor | Lele, Sanjiva K. (Sanjiva Keshava), 1958- |
| Thesis advisor | Lele, Sanjiva K. (Sanjiva Keshava), 1958- |
| Thesis advisor | Eaton, John K |
| Thesis advisor | Moin, Parviz |
| Advisor | Eaton, John K |
| Advisor | Moin, Parviz |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Rathakrishnan Bhaskaran. |
|---|---|
| Note | Submitted to the Department of Mechanical Engineering. |
| Thesis | Thesis (Ph. D.)--Stanford University, 2010. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2010 by Rathakrishnan Bhaskaran
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