... at 1180 ° C and 180 m/s ( M = 0.25 ) . Both cylindrical and shaped holes, with and without thermal barrier coating, were studied over a range of blowing ratios from 0.5 to 4.0. Coolant density ratios were maintained at values from 2.1 to 2.4. Deposition patterns generated with the cylindrical film cooling...

...Christian Heneka; Achmed Schulz; Hans-Jörg Bauer; Andreas Heselhaus; Michael E. Crawford An experimental study on film cooling performance of laterally inclined diffuser shaped cooling holes is presented. The measurements have been conducted on a flat plate with coolant ejected from a plenum...

... out at low speed ( M 2 is = 0.2 ) and low inlet turbulence intensity level, with coolant mass flow rate ratio varied within the 0.5–2.5% range. Pressure probe traverses were performed downstream of the vane trailing edge to show the secondary flow field modifications and to evaluate trench additional...

... investigated the combined influence of all cooling circuits. Heat-flux measurements for the airfoil, platform, tip, and root of the turbine blade, as well as the shroud and the vane side of the purge cavity, are used to track the influence of cooling flow. By independently varying the coolant flow rate through...

...R. M. Mathison; C. W. Haldeman; M. G. Dunn Heat-flux measurements are presented for a one-and-one-half stage high-pressure turbine operating at design-corrected conditions with modulated cooling flows in the presence of different inlet temperature profiles. Coolant is supplied from a heavily film...

...Diganta P. Narzary; Kuo-Chun Liu; Akhilesh P. Rallabandi; Je-Chin Han Adiabatic film-cooling effectiveness is examined on a high-pressure turbine blade by varying three critical engine parameters, viz., coolant blowing ratio, coolant-to-mainstream density ratio, and freestream turbulence intensity...

... to an aeroengine high-pressure turbine stage. It is found that, if the efficiency definition includes all irreversibilities, the penalty associated with film cooling would be 8.0%. However, if the pragmatic approach is adopted whereby the unavoidable entropy generated due to the equilibration of coolant...

... a hot-streak profile in a way similar to that observed for a radial profile. Differences in core to coolant temperature ratio cause the uniform profile to show different coolant effects, but the overall spread of the cooling appears similar. As with the uniform and radial profiles, the profile shape...

...Chao Zhou; Howard Hodson Experimental, analytical, and numerical methods have been employed to study the aerodynamic performance of four different cooled tips with coolant mass ratios between 0% and 1.2% at three tip gaps of 1%, 1.6%, and 2.2% of the chord. The four cooled tips are two flat tips...

...-space cavity, and five cylinders that represent the blockage due to the leading edge of the rotor airfoils. The experimental program investigated two cylinder diameters and three clocking positions for a nominal coolant flow rate. Comparisons are made between the computed and measured flow-fields...

.... For the contoured passage, measurements were performed both on the flat endwall and on the contoured endwall. Fully expanded film cooling holes were distributed on the endwall surface preceded by a two-dimensional slot normal to the inlet axis. Results indicated that the coolant coverage from the upstream leakage...

... for relatively higher-pressure coolant flows. This leakage is intended to prevent ingestion of the hot combustion flow in the primary gas path. At the vane endwall, this leakage flow can interfere with the complex vortical flow present there and thus affect the heat transfer to that surface. To determine...

... loading conditions, which results in an intensification of the secondary flow and enhanced interaction with the injected coolant. The investigated profile is based on a near-hub section of the nozzle guide vane of a highly loaded gas turbine. The aerodynamic performance was investigated using pneumatic...

... receptivity to coolant flow and blowing ratio. On a number basis, 85–90% of the 10 μ m particles, 70–65% of 7 μ m particles, 40–50% of 5 μ m particles, 15% of 3 μ m particles, and less than 1% of 1 μ m particles deposit on the surface. Overall there is a slight decrease in percentage of particles deposited...

...Will F. Colban; Karen A. Thole; David Bogard A common method of optimizing coolant performance in gas turbine engines is through the use of shaped film-cooling holes. Despite widespread use of shaped holes, existing correlations for predicting performance are limited to narrow ranges of parameters...

... with a geometry typical of a real gas turbine nozzle vane. The cooling scheme consists of four rows of cylindrical holes. Tests have been carried out at low speed ( Ma 2 is = 0.2 ) with a low inlet turbulence intensity level (1.0%) and with a coolant to mainstream mass flow ratio varied in the range from 0...

...A. Suryanarayanan; B. Ozturk; M. T. Schobeiri; J. C. Han Film-cooling effectiveness is measured on a rotating turbine blade platform for coolant injection through discrete holes using pressure sensitive paint technique. Most of the existing literatures provide information only for stationary...

... costs and time. In the present work, a low-pressure turbine was analyzed, modeling the rotor-stator including the wheel space region. Attention was focused on the interaction between the coolant and the main flow in order to obtain a more detailed understanding of the behavior of the angel wings...

... path, for aeroengines these particles are pulled into the coolant system where they can clog cooling passages and erode internal surfaces. Unlike previous research that focused on deposition and erosion within the main gas path, this study evaluated blocking in a double wall liner whereby both...

... ) was either 0 rpm or 800 rpm; the film cooling blowing ratios ranged from 0.4 to 2.0, and two averaged density ratios of 1.02 and 1.53 were employed with air and carbon dioxide ( CO 2 ) as the coolant, respectively. Thermochromic liquid crystal was used to measure the solid surface temperature distributions...