Thermal hydraulic characteristics of coolant flow through passages consisting of rib turbulators, pin fin array and trailing edge slot are reported. Channels of straight, trapezoidal and curved shapes are considered. Continuity, momentum and energy equations for a three dimensional incompressible flows are solved. A constant heat flux value is specified over the coolant channel walls, rib surfaces and circumferential faces of the pin-fins. Total pressure loss coefficient, pin end-wall and pin surface averaged Nusselt number are estimated and presented for the pin array, for Reynolds number ranging from 20,000 to 40,000. Cambered channels showed highest pin end wall averaged heat transfer than trapezoidal channel, which is higher than the straight channel. Copyright © 2007 by ASME.

B. V.S.S.S. Prasad

Department of Mechanical Engineering

Pin fin arrays

Thermal hydraulic

Trailing edges

Turbulators

Computational methods

Coolants

Cooling

Heat flux

Nusselt number

Reynolds number

Turbines

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Computational Investigations in the Trailing Edge Region of Cooled Turbine Vane: Comparison of Different Channel Shapes

Proceedings of the ASME Turbo Expo

The present work is concerned with the computational analysis of flow and heat transfer from the circular pin fin channels in the trailing edge region of a gas turbine vane. Combined effects of channel shape, conjugate boundary condition and flow orientation are studied. Four different channel shapes: Straight Rectangular, Straight Converged, Cambered Rectangular and Cambered Converged are considered. Both straight and lateral coolant entry are investigated at a nominal Reynolds number of 20,000. Numerical simulations are performed for the steady, incompressible, turbulent flow with the help of a computational fluid dynamics code. A structured hexahedral mesh having about 5 million cells is generated in the domain. The computational methodology is validated against the data from a standard ERCOFTAC bench mark test case. Flow and heat transfer characteristics at various locations in the channel and the axial temperature variation for a chosen pin are reported.

Effect of coolant entry orientation on flow and heat transfer in the trailing region channels of a gas turbine vane

A numerical investigation is carried out for estimating the influence of rib turbulators on heat transfer and pressure drop of staggered non-uniform pin-fin arrays of different shapes, in a simulated cambered vane trailing region. Pin-fins of square, circular and the diamond shapes, each of two sizes (d) were chosen. The ratio of span-wise pitch to longitudinal pitch is 1.06 and that to the pin size are 4.25 and 3.03, for all pin shapes. A constant heat flux boundary condition is assumed over the coolant channel walls, rib surfaces and circumferential faces of the pin-fins. Reynolds number is varied (20,000&lt;ReD&lt;40,000) by changing the coolant outlet to inlet pressure ratio. Pin end-wall and pin surface averaged heat transfer coefficients and Nusselt numbers are estimated and detailed contours of heat transfer coefficient on both the pressure and suction surfaces are presented. Whilst there is an enhancement in heat transfer and pressure drop with ribs for all the pin shapes, diamond pins have shown the highest enhancement values for both ribbed and non-ribbed configuration. Copyright © 2006 by ASME.

Influence of rib turbulators on pin-fin heat transfer in the trailing region of gas turbine vane - A numerical study

Fluent Aphasia

Non-fluent and fluent aphasic speakers. What are the differences?

Journal of Turbomachinery

Turbulent Augmentation of Internal Convection Over Pins in Staggered-Pin Fin Arrays

International Journal of Heat and Mass Transfer

Detailed heat transfer characteristic comparison in straight and 90-deg turned trapezoidal ducts with pin-fin arrays

An Experimental Investigation of the Rib Surface-Averaged Heat Transfer Coefficient in a Rib-Roughened Square Passage

Computational investigations in the trailing edge region of cooled turbine vane - Comparison of different channel shapes