Convective heat transfer and hydrodynamics of flow at the endwall around a turbine blade under the influence of a magnetic field

The present study analyses the influence of magnetohydrodynamics on endwall heat transfer in turbine blades using computational fluid dynamics simulations. The simulations consider the three-dimensional geometry of the turbine blade, the magnetic intensity, and the boundary conditions. The outcome revealed the existence of a magnetic field can outstandingly increase the pitch-averaged film cooling effectiveness and endwall heat transfer, particularly near the edges of the turbine vane with an optimal magnetic field. This results in a more uniform distribution of heat transfer along the endwall and can help to reduce hot spots and prevent thermal damage to the blade. The research also highlights the importance of considering the magnetic intensity and its impact on the flow characteristics and heat transfer when designing turbine blades for high-speed applications. By optimizing the design of the turbine blades to take into account the magnetohydrodynamic effect, engineers can improve the overall performance and lifespan of these critical components. Numerical simulations had been utilized to forecast the impacts of contouring of endwalls efficiently, employing the secondary kinetic energy coefficient as the accomplished parameter demonstrated in the current investigation. A reduction in endwall heat load with enhanced net heat flux reduction and aerodynamic performance is reported for a non-axisymmetrically contoured endwall subjected to optimal magnetic field strength. The novelty of the present study is the establishment of the impact of vortices on endwall heat transfer with respect to the vane under the influence of magnetohydrodynamics to reduce the weight and cost of a turbine engine.

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