A major objective in advancing gas turbine technologies is to increase the temperature limit associated with operation of the turbine blades. For example, it is common to use internal cooling by including flow channels within the blades and routing air through the channels. We wish to assess the effect of such a scheme by approximating the blade as a rectangular solid with rectangular channels. The blade, which has a thermal conductivity of k = 25 W/m · K, is 6 mm thick, and each channel has a 2 mm × 6 mm rectangular cross section, with a 4-mm spacing between adjoining channels. Under operating conditions for which ho = 1000 W/m² · K, T2,0 = 1700 K, hi = 200 W/m² · K, and Tø,i = 400 K, determine the temperature field in the turbine blade and the rate of heat transfer per unit length to the channel. At what location is the temperature a maximum? Air channel Conbustion gases 6 mm Combustion Turbine blade, gases

A major objective in advancing gas turbine technologies is to increase the temperature limit associated with operation of the turbine blades. For example, it is common to use internal cooling by including flow channels within the blades and routing air through the channels. We wish to assess the effect of such a scheme by approximating the blade as a rectangular solid with rectangular channels. The blade, which has a thermal conductivity of k = 25 W/m · K, is 6 mm thick, and each channel has a 2 mm × 6 mm rectangular cross section, with a 4-mm spacing between adjoining channels. Under operating conditions for which ho = 1000 W/m² · K, T2,0 = 1700 K, hi = 200 W/m² · K, and Tø,i = 400 K, determine the temperature field in the turbine blade and the rate of heat transfer per unit length to the channel. At what location is the temperature a maximum? Air channel Conbustion gases 6 mm Combustion Turbine blade, gases

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.53P

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