... in a typical RDC in order to define basic cooling requirements for possible actual design of the combustor. Along with this, a simplified approach has been implemented for the estimation of the requirements for cold side convection cooling with respect to different heat load scenarios, shedding light...

...   ( surface   temperature   boundary   condition ) (4) x → ∞ ,   T = T i   ( semi − infinite   solid   assumption ) The convective heat flux at the surface can be defined as (5) q ″ = h ( T m − T w ) = − k ∂ T...

... RANS applying a k - ε - v 2 - f turbulence model and the Spalart and Allmaras turbulence model and detached-eddy simulation (DES) based on the Spalart and Allmaras turbulence model are addressed to solve thermal convection. The CFD calculations were conducted by simulating a semicircular model...

...) with three different turbulence models: the k- ε model, the SST reattachment model, and the Omega Reynolds stress (ORS) turbulence model. Both the experimental and numerical results showed a significant influence of the turning vane configuration on the heat transfer and pressure drop in the convective...

... ) Subscripts ax axial chord conv heat transfer through convection exit exit of the vane passage at the throat in measured at the inlet of the cascade inv inviscid conditions wall wall measurement ∞ freestream Thrift , A. A. , Thole , K...

... the blade tip-cap inside the turbine blade. Improved internal convective cooling is therefore required to increase the blade tip lifetime. Dimples and protrusions are well recognized as effective devices to augment heat transfer in various applications. In this paper, enhanced heat transfer of an internal...

...L. He; M. L. G. Oldfield The primary requirement for high pressure turbine heat transfer designs is to predict blade metal temperature. There has been a considerable recent effort in developing coupled fluid convection and solid conduction (conjugate) heat transfer prediction methods...

.... Local convection coefficients are the result of both the jet impact, as well as the channel flow produced from the exiting jets. Numerous studies have explored the effects of jet array and channel configurations on both target and jet plate heat transfer coefficients. However, most current studies use...

...Stephen T. McClain; B. Keith Hodge; Jeffrey P. Bons The discrete-element model for flows over rough surfaces considers the heat transferred from a rough surface to be the sum of the heat convected from the flat surface and the heat convected from the individual roughness elements to the fluid...

...Sunil Patil; Santosh Abraham; Danesh Tafti; Srinath Ekkad; Yong Kim; Partha Dutta; Hee-Koo Moon; Ram Srinivasan Experiments and numerical computations are performed to investigate the convective heat transfer characteristics of a gas turbine can combustor under cold flow conditions in a Reynolds...

... are commonly used to increase heat transfer by generating turbulence and to provide a greater convective surface area. Because of the increasing complexity in airfoil design and manufacturing, a methodology is needed to accurately measure the convection coefficient of a rib with a complex shape. Previous...

... the boundary layer to the point of separation (thus increasing loss). In the turbine, roughness has the added effect of augmenting convective heat transfer. While this is desirable in an internal turbine coolant channel, it is clearly undesirable on the external turbine surface. Recent advances in roughness...

... internally through the rotating hardware and externally through radiation, conduction, and convection. In case where the bearing chamber is in close proximity to the engine’s hot section, the external heat flux may be significant. This is, for example, the case when oil pipes pass through the turbine struts...

...Giovanni Tanda; Roberto Abram, Ph.D. student Local and average Nusselt numbers and friction factors are presented for rectangular channels with an aspect ratio of 5 and angled rib turbulators inclined at 45 deg with parallel orientations on one and two surfaces of the channel. The convective fluid...

... Facility located at the Air Force Research Laboratory using an inlet profile generator. Results indicate that the convection heat transfer coefficients are influenced by both the inlet pressure profile shape and the location along the endwall. The heat transfer driving temperature for inlet profiles...

...Steven J. Thorpe; Roger W. Ainsworth In a modern gas turbine engine, the outer casing (shroud) of the shroudless high-pressure turbine is exposed to a combination of high flow temperatures and heat transfer coefficients. The casing is consequently subjected to high levels of convective heat...

...Ronald S. Bunker The objective of the present study is to demonstrate a method to provide substantially increased convective heat flux on the internal cooled tip cap of a turbine blade. The new tip-cap augmentation consists of several variations involving the fabrication or placement of arrays...

...A. de la Loma; G. Paniagua; D. Verrastro; P. Adami This paper reports the external convective heat transfer distribution of a modern single-stage transonic turbine together with the physical interpretation of the different shock interaction mechanisms. The measurements have been performed...

... , the smooth wall value of Reynolds analogy, for a turbulent boundary layer was 1.2. 08 09 2006 15 11 2006 25 03 2008 convection gas turbines blades surface roughness flow simulation thermal barrier coatings boundary layer turbulence wind tunnels Land-based and aircraft gas...

...R. D. Stieger; H. P. Hodson This paper presents two-dimensional LDA measurements of the convection of a wake through a low-pressure turbine cascade. Previous studies have shown the wake convection to be kinematic, but have not provided details of the turbulent field. The spatial resolution...