Showing papers by "Richard J Goldstein published in 2010"
TL;DR: A review of the heat transfer literature published in 2005 can be found in this article, where the authors restrict themselves to papers published in English through a peer-review process, with selected translations from journals published in other languages.
96 citations
TL;DR: A review of heat transfer literature published in 2004 in English language, including some translations of foreign language papers, is presented in this paper, where papers are grouped into subject-oriented sections and further divided into sub-fields.
56 citations
01 Jan 2010
TL;DR: In this paper, the effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting air through a slot upstream of the blade row at 45° to the endwall, for Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1 and 1.5.
Abstract: Mass transfer measurements on the endwall and blade suction surfaces are performed in a five-blade linear cascade with a high-performance rotor blade profile. The effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting air through a slot upstream of the blade row at 45° to the endwall, for Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1 and 1.5. Detailed maps of cooling effectiveness on the passage endwall and blade suction surface are generated for the cases of injection of naphthalene-free and naphthalene-saturated air. Oil-dot visualization indicates that with injection, a recirculation region is set up upstream of the leading edge, and the growth of the passage vortex is altered. The coolant exiting from the slot is drawn to the suction side of the blade and is pushed up along the suction surface of the blade by the secondary flow. For blowing ratios of 0.5 and 1.0, only a little coolant reaches the pressure side in the aft part of the passage. However, at a blowing ratio of 1.5, there is a dramatic change in the flow structure. Both the oil dot visualization and the cooling effectiveness maps indicate that at this blowing ratio, the coolant exiting the slot has sufficient momentum to closely follow the blade profile, and is not significantly entrained into the passage vortex. As a result, high cooling effectiveness values are obtained at the pressure side of the endwall, well into the mid-chord and aft portions of the blade passage.Copyright © 2010 by ASME
42 citations
TL;DR: In this paper, the effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting air through a slot upstream of the blade row at 45° to the endwall, for Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1 and 1.5.
Abstract: Mass transfer measurements on the endwall and blade suction surfaces are performed in a five-blade linear cascade with a high-performance rotor blade profile. The effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting air through a slot upstream of the blade row at 45° to the endwall, for Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1 and 1.5. Detailed maps of cooling effectiveness on the passage endwall and blade suction surface are generated for the cases of injection of naphthalene-free and naphthalene-saturated air. Oil-dot visualization indicates that with injection, a recirculation region is set up upstream of the leading edge, and the growth of the passage vortex is altered. The coolant exiting from the slot is drawn to the suction side of the blade and is pushed up along the suction surface of the blade by the secondary flow. For blowing ratios of 0.5 and 1.0, only a little coolant reaches the pressure side in the aft part of the passage. However, at a blowing ratio of 1.5, there is a dramatic change in the flow structure. Both the oil dot visualization and the cooling effectiveness maps indicate that at this blowing ratio, the coolant exiting the slot has sufficient momentum to closely follow the blade profile, and is not significantly entrained into the passage vortex. As a result, high cooling effectiveness values are obtained at the pressure side of the endwall, well into the mid-chord and aft portions of the blade passage.Copyright © 2010 by ASME
38 citations
3 citations
TL;DR: In this article, the effects of wall shear on a two-dimensional turbulent boundary layer were investigated at 12 streamwise locations with four surface-to-freestream velocity ratios and a momentum-based Reynolds number between 770 and 1776.
Abstract: A parametric study investigates the effects of wall shear on a two-dimensional turbulent boundary layer. A belt translating along the direction of the flow imparts the shear. Velocity measurements are performed at 12 streamwise locations with four surface-to-freestream velocity ratios (0, 0.38, 0.52, and 0.65) and a momentum-based Reynolds number between 770 and 1776. The velocity data indicate that the location of the "virtual origin" of the turbulent boundary layer "moves" downstream toward the trailing edge of the belt with increasing surface velocity. The highest belt velocity ratio (0.65) results in the removal of the "inner" region of the boundary layer. Measurements of the streamwise turbulent kinetic energy show an inner scaling at locations upstream and downstream of the belt, and the formation of a new self-similar structure on the moving surface itself. Good agreement is observed for the variation in the shape factor (H) and the skin friction coefficient (c f ) with the previous studies. The distribution of the energy spectrum downstream of the belt indicates peak values concentrated around 1 kHz for the stationary belt case in the near wall region (30 < y + < 50). However, with increasing belt velocity, this central peak plateaus over a wide frequency range (0.9―4 kHz).
1 citations
1 citations
TL;DR: In this paper, mass transfer measurements on a flat plate downstream of a belt moving in the same direction of the freestream study the effect of the upstream shear on the heat (mass) transfer for four belt-freestream velocity ratios.
Abstract: Mass transfer measurements on a flat plate downstream of a belt moving in the same direction of the freestream study the effect of the upstream shear on the heat (mass) transfer for four belt-freestream velocity ratios. With an increase in this ratio, the "virtual origin" of the turbulent boundary layer "moves" downstream toward the trailing edge of the belt. This is verified from the variation of the Stanton number versus the Reynolds number plots. As the "inner" region of the boundary layer is removed for a belt speed of u w = 10 m/s (freestream velocity u in ≈ 15.4 m/s), a corresponding local minimum in the variation of the Stanton number is observed. Downstream of this minimum, the characteristics of the turbulent boundary layer are restored and the data fall back on the empirical variation of Stanton with Reynolds number.