... thermodynamic loss increase of about 0.7% at low coolant injection rates. Increasing the blowing rates, the additional loss vanishes. Boletis , E. , 1985 , “ Effects of Outer Diameter Endwall Contouring on the Three-Dimensional Flow Field in an Annular Turbine Nozzle Guide Vane: Part I—Experimental...

.... Axisymmetric and three-dimensional (3D) sector CFD models are considered. In the 3D sector models, the preswirl nozzles or receiver holes are represented as axisymmetric slots so that steady state solutions can be assumed. A number of commonly used turbulence models are tested in three different CFD codes...

...Colin D. Copeland; Ricardo Martinez-Botas; Martin Seiler Circumferentially divided, double entry turbocharger turbines are designed with a dividing wall parallel to the machine axis such that each entry feeds a separate 180 deg section of the nozzle circumference prior to entry into the rotor...

... and a reference new vane were made. Coordinates for the three airfoil profiles were obtained from the nozzle guide vanes of refurbished turboshaft engines using 3D optical scanning and digital modeling. The repaired profiles showed differences in geometry in comparison with the new vane, particularly near...

...Michela Massini; Robert J. Miller; Howard P. Hodson This paper presents the design, manufacture, and testing of a new probe for the measurement of temperature and pressure in engine environments. The probe consists of a choked nozzle located in the flow and a system downstream including a cooler...

.... Such contouring can lead to significant changes in the endwall flows, thereby altering the heat transfer. This paper investigates the effect of axisymmetric contouring on the endwall heat transfer of a nozzle guide vane. Heat transfer measurements are performed on the endwalls of a planar and contoured passage...

...A. A. Thrift; K. A. Thole; S. Hada Gas turbine designs seek improved performance by modifying the endwalls of nozzle guide vanes in the engine hot section. Within the nozzle guide vanes, these modifications can be in the form of an axisymmetric contour as the area contracts from the combustor...

... 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...

...-dimensionally contoured duct. As a result, a transonic and periodic flow, highly representative of the engine aerodynamic field, is established: Inlet turbulence levels, mainstream Mach and Reynolds numbers, and coolant-to-mainstream total pressure ratio are matched. Since the fully three-dimensional nozzle...

... achieved when reducing the number of nozzles and hence the injection mass flow. It was also found that injection of hot air, at temperatures comparable to air that bled off at a following stage, had no penalty on the stability enhancement. Investigation of the influence of air injection on radial work...

...V. U. Kakade; G. D. Lock; M. Wilson; J. M. Owen; J. E. Mayhew This paper investigates heat transfer in a rotating disk system using preswirled cooling air from nozzles at high and low radius. The experiments were conducted over a range of rotational speeds, flow rates, and preswirl ratios. Narrow...

... reflecting between stationary nozzles and moving blades of a water-table turbine at Lehigh University, on the description of the various types of such waves, and on an explanation of some of the resonant blade excitation frequencies observed by National Advisory Committee for Aeronautics (NACA) in a turbine...

...Gabriele D’Ippolito; Vincenzo Dossena; Alessandro Mora The work proposes a detailed description of the flow field throughout leaned turbine nozzles and reports a sensitivity analysis with respect to the lean angle. A phenomenological approach focuses the attention on pressure contours distribution...

...T. Povey; M. Sharpe; A. Rawlinson Nozzle guide vane (NGV) flow capacity is perhaps the most important parameter for engine optimization. Inaccurate evaluation of capacity would lead to incorrect performance evaluation, and unmatched stages. A new semi-transient technique has been developed...

... single-droplet evaporation model augmented with an empirical splashing model, which, as input, uses measurements of droplet spectra data taken on water injection nozzles in an intake rig configured with realistic length scales. In addition, a wetted-airfoil-surface flow-angle deviation model is applied...

...Giovanna Barigozzi; Giuseppe Franchini; Antonio Perdichizzi; Marco Quattrore The present paper investigates the effects of endwall injection of cooling flow on the aerodynamic performance of a nozzle vane cascade with endwall contouring. Tests have been performed on a seven vane cascade...

...Shu Fujimoto; Yoji Okita; Yoshitaka Fukuyama; Takashi Yamane; Fujio Mimura; Masahiro Matsushita; Toyoaki Yoshida An innovative internal cooling structure named multislot cooling has been invented for high-pressure turbine (HPT) nozzles and blades. This cooling structure has been designed...

... that the fan rotational speed scales with the engine mass flow rate. Making use of the known values of the nozzle coefficients, we deduce the stagnation pressure loss of the fan stage, which rises significantly as the mass flow rate increases. In order to better understand this behavior, numerical simulations...

...Srithar Rajoo; R. F. Martinez-Botas The unsteady behavior of a nozzled turbocharger turbine under pulsating flow conditions has been studied experimentally in a cold flow test facility that replicates engine pulses. The results presented are obtained at a turbine speed of 48,000 rpm for pulsating...

... losses in axial turbines. Using a frozen flow assumption, the time-resolved data are used to estimate the axial velocity gradients, which are then used to evaluate the streamwise vorticity and dissipation. The nonaxisymmetric endwall profiling of the first nozzle guide vane show reductions in dissipation...