http://scitation.aip.org/ J. Turbomach.: All Topics http://link.aip.org/link/doi/10.1115/1.4000485 P. Schuepbach, R. S. Abhari, M. G. Rose, T. Germain, I. Raab, and J. Gier<br/> In high-pressure turbines, a small amount of air is ejected at the hub rim seal to cool and prevent the ingestion of hot gases into the cavity between the stator and the disk. This paper presents an experimental study of the flow mechanisms that are associated with injection through the hub rim seal ... [J. Turbomach. 132, 021021 (2010)] published Thu Jan 21, 2010. http://link.aip.org/link/doi/10.1115/1.3106702 N. D. Cardwell, K. A. Thole, and S. W. Burd<br/> Gas turbines are not generally designed for operation with a particle laden inlet flow but, in fact, are commonly operated in unclean environments resulting in dirt, sand, and other debris ingestion. In addition to the negative effects within the main gas path, for aeroengines these particles are pu ... [J. Turbomach. 132, 021020 (2010)] published Thu Jan 21, 2010. http://link.aip.org/link/doi/10.1115/1.3147103 Shyy Woei Chang, Tong-Miin Liou, Tsun Lirng Yang, and Guo Fang Hong<br/> Endwall heat transfer measurements for a radially rotating rectangular pin-fin channel with the width-to-height ratio (aspect ratio) of 8 are performed at the parametric conditions of 5000<=Re<=20,000, 0<=Ro<=1.4, and 0.1<=Deltarho/rho<=0.21. Centerline heat transfer levels along the leading and tra ... [J. Turbomach. 132, 021019 (2010)] published Thu Jan 21, 2010. http://link.aip.org/link/doi/10.1115/1.3104611 Richard Williams, David Gregory-Smith, Li He, and Grant Ingram<br/> Large tip clearances typically in the region of 6% exist in the high pressure (HP) stages of compressors of industrial gas turbines. Due to the relatively short annulus height and significant blockage, the tip clearance flow accounts for the largest proportion of loss in the HP. Therefore increasing ... [J. Turbomach. 132, 021018 (2010)] published Wed Jan 20, 2010. http://link.aip.org/link/doi/10.1115/1.3145103 Juan Du, Feng Lin, Hongwu Zhang, and Jingyi Chen<br/> A numerical investigation on the self-induced unsteadiness in tip leakage flow is presented for a transonic fan rotor. NASA Rotor 67 is chosen as the computational model. It is found that under certain conditions the self-induced unsteadiness can be originated from the interaction of two important d ... [J. Turbomach. 132, 021017 (2010)] published Wed Jan 20, 2010. http://link.aip.org/link/doi/10.1115/1.3144164 S. K. Krishnababu, H. P. Hodson, G. D. Booth, G. D. Lock, and W. N. Dawes<br/> A numerical investigation of the flow and heat transfer characteristics of tip leakage in a typical film cooled industrial gas turbine rotor is presented in this paper. The computations were performed on a rotating domain of a single blade with a clearance gap of 1.28% chord in an engine environment ... [J. Turbomach. 132, 021016 (2010)] published Wed Jan 20, 2010. http://link.aip.org/link/doi/10.1115/1.3104612 Nobuyuki Yamaguchi, Masayuki Ogata, and Yohei Kato<br/> An improved construction of air-separator device, which has radial-vanes embedded within its inlet circumferential opening with their leading-edges facing the moving tips of the fan rotor-blades so as to scoop the tip flow, was investigated with respect to the stall-prevention effect on a low-speed, ... [J. Turbomach. 132, 021015 (2010)] published Wed Jan 13, 2010. http://link.aip.org/link/doi/10.1115/1.3104615 Tom Verstraete, Sergio Amaral, Rene Van den Braembussche, and Tony Arts<br/> This second paper presents the aerothermal optimization of the first stage rotor blade of an axial high pressure (HP) turbine by means of the conjugate heat transfer (CHT) method and lifetime model described in Paper I. The optimization system defines the position and diameter of the cooling channel ... [J. Turbomach. 132, 021014 (2010)] published Wed Jan 13, 2010. http://link.aip.org/link/doi/10.1115/1.3104614 Sergio Amaral, Tom Verstraete, Rene Van den Braembussche, and Tony Arts<br/> This first paper describes the conjugate heat transfer (CHT) method and its application to the performance and lifetime prediction of a high pressure turbine blade operating at a very high inlet temperature. It is the analysis tool for the aerothermal optimization described in a second paper. The CH ... [J. Turbomach. 132, 021013 (2010)] published Wed Jan 13, 2010. http://link.aip.org/link/doi/10.1115/1.3103928 D. X. Wang, L. He, Y. S. Li, and R. G. Wells<br/> This is the second part of a two-part paper. First, the design-optimization system based on the adjoint gradient solution approach as described in Part I is introduced. Several test cases are studied for further validation and demonstration of the methodology and implementation. The base-line adjoin ... [J. Turbomach. 132, 021012 (2010)] published Wed Jan 13, 2010. http://link.aip.org/link/doi/10.1115/1.3072498 D. X. Wang and L. He<br/> The adjoint method for blade design optimization will be described in this two-part paper. The main objective is to develop the capability of carrying out aerodynamic blading shape design optimization in a multistage turbomachinery environment. To this end, an adjoint mixing-plane treatment has been ... [J. Turbomach. 132, 021011 (2010)] published Wed Jan 13, 2010. http://link.aip.org/link/doi/10.1115/1.3104616 Beni Cukurel, Patrick B. Lawless, and Sanford Fleeter<br/> An efficient diffuser is essential to a modern compressor stage due to its significance in stage performance, durability, and operability. To address the need for data that describe the complex, unsteady flow field in a vaned diffuser, particle image velocity is utilized to characterize the spanwise ... [J. Turbomach. 132, 021010 (2010)] published Tue Jan 12, 2010. http://link.aip.org/link/doi/10.1115/1.3104613 Nobuyuki Yamaguchi, Masayuki Ogata, and Yohei Kato<br/> The stall-prevention effect of air separators incorporating radial vanes in place of the existing axial vanes was investigated on a low-speed, single-stage, lightly loaded axial-flow fan for effective and compact air separators of a simplified structure. From the survey, paying attention to several ... [J. Turbomach. 132, 021009 (2010)] published Tue Jan 12, 2010. http://link.aip.org/link/doi/10.1115/1.3103926 P. Schupbach, R. S. Abhari, M. G. Rose, T. Germain, I. Raab, and J. Gier<br/> This paper is the second part of a two part paper that reports on the improvement of efficiency of a one and a half stage high work axial flow turbine. The first part covered the design of the endwall profiling, as well as a comparison with steady probe data; this part covers the analysis of the tim ... [J. Turbomach. 132, 021008 (2010)] published Tue Jan 12, 2010. http://link.aip.org/link/doi/10.1115/1.3106706 T. Germain, M. Nagel, I. Raab, P. Schupbach, R. S. Abhari, and M. Rose<br/> This paper is the first part of a two part paper reporting the improvement of efficiency of a one-and-half stage high work axial flow turbine by nonaxisymmetric endwall contouring. In this first paper the design of the endwall contours is described, and the computational fluid dynamics (CFD) flow pr ... [J. Turbomach. 132, 021007 (2010)] published Tue Jan 12, 2010. http://link.aip.org/link/doi/10.1115/1.3142859 M. Pau, G. Paniagua, D. Delhaye, A. de la Loma, and P. Ginibre<br/> The sealing of the stator-rotor gap and rotor-platform cooling are vital to the safe operation of the high-pressure turbine. Contrary to the experience in subsonic turbines, this paper demonstrates the potential to improve the efficiency in transonic turbines at certain rim seal rates. Two types of ... [J. Turbomach. 132, 021006 (2010)] published Mon Jan 11, 2010. http://link.aip.org/link/doi/10.1115/1.3140824 K. M. Guleren, I. Afgan, and A. Turan<br/> The turbulent flow inside a low-speed centrifugal compressor at design condition is investigated using large-eddy simulation (LES) comprising of up to 26 x 10 computational volume cells. Unlike in the past, the current study's special emphasis is placed on the turbulence field evolution inside the i ... [J. Turbomach. 132, 021005 (2010)] published Mon Jan 11, 2010. http://link.aip.org/link/doi/10.1115/1.3066315 J. P. Bons<br/> The effects of surface roughness on gas turbine performance are reviewed based on publications in the open literature over the past 60 years. Empirical roughness correlations routinely employed for drag and heat transfer estimates are summarized and found wanting. No single correlation appears to ca ... [J. Turbomach. 132, 021004 (2010)] published Mon Jan 11, 2010. http://link.aip.org/link/doi/10.1115/1.3140823 S. Todd Bailie, Wing F. Ng, and William W. Copenhaver<br/> The main contributor to the high cycle fatigue of compressor blades is the response to aerodynamic forcing functions generated by an upstream row of stators or inlet guide vanes. Resonant response to engine order excitation at certain rotor speeds can be especially damaging. Studies have shown that ... [J. Turbomach. 132, 021003 (2009)] published Thu Dec 31, 2009. http://link.aip.org/link/doi/10.1115/1.3140283 Ioannis Ieronymidis, David R. H. Gillespie, Peter T. Ireland, and Robert Kingston<br/> Detailed measurements of the heat transfer coefficient (htc) distributions on the internal surfaces of a novel gas turbine blade cooling configuration were carried out using a transient liquid crystal technique. The cooling geometry, in which a series of racetrack passages are connected to a central ... [J. Turbomach. 132, 021002 (2009)] published Thu Dec 31, 2009. http://link.aip.org/link/doi/10.1115/1.3140282 Andrew C. Chambers, David R. H. Gillespie, Peter T. Ireland, and Robert Kingston<br/> Impingement systems are common place in many turbine cooling applications. Generally these systems consist of a target plate that is cooled by the impingement of multiple orthogonal jets. While it is possible to achieve high target surface heat transfer with this configuration, the associated pressu ... [J. Turbomach. 132, 021001 (2009)] published Thu Dec 31, 2009.