...Pawel J. Przytarski; Davide Lengani; Daniele Simoni; Andrew P. S. Wheeler In this article, we study the role of turbulence transport on loss prediction using high fidelity scale-resolving simulations. For this purpose, we use eight high-fidelity simulation datasets and compute flux of entropy...

... the 1.5-stage turbine by performing computational fluid dynamics simulations with the simcenter star-ccm + software. The mathematical model of the simulations consisted of the ensemble-averaged unsteady-state mass, momentum, and energy equations complemented by the SST turbulence model. The authors...

...Thomas O. Jelly; Wagih Abu Rowin; Nicholas Hutchins; Daniel Chung; Koichi Tanimoto; Takuo Oda; Richard D. Sandberg Direct numerical simulations of incompressible turbulent forced convection over irregular, anisotropic surface roughness in a pressure-driven plane channel flow have been performed...

... the oil film thickness distribution and interface velocity at different engine operating conditions. Currently, Reynolds-averaged Navier–Stokes (RANS) CFD uses a semi-empirical method of turbulence damping, which is inaccurate for wavy films and so impacts the modeling of bearing chambers and gearboxes...

...Huang Chen; Yuanchao Li; Subhra Shankha Koley; Joseph Katz Challenges in turbulence modeling in the tip region of turbomachines include anisotropy, inhomogeneity, and non-equilibrium conditions, resulting in poor correlations between Reynolds stresses and the corresponding mean strain-rate...

... study focuses on the effect of resolution on flow physics and loss generation and uses a compressor cascade subjected to freestream turbulence. The results show that both resolving local entropy generation rate and capturing the inception and growth of instabilities are critical to accuracy of loss...

... a single blade passage back into the inlet of the computational domain. As a result, a type of repeating-passage simulation is obtained such as observed by an embedded blade-row. We find that freestream turbulence levels rise significantly as the size of the rotor-stator axial gap is reduced...

... = heat transfer analog NGV = nozzle guide vane Tu = turbulence PS, SS = pressure side, suction side LE, TE = leading edge, trailing edge MUSCL = monoton upstream-centered scheme for conservation laws n1 = instrumented vane 1 n2 = instrumented vane 2 C1...

...Vladimir Vassiliev; Stefan Irmisch; Samer Abdel-Wahab; Andrey Granovskiy The flow in exhaust diffusers along with the channel geometry strongly depends on the inflow conditions, including Mach number level, total pressure distribution, flow angle, and turbulence. In the first part of this paper...

... on the physics of flow and heat transfer in the rotor tip, casing, and hub regions. The simulation was performed using the unsteady Reynolds-averaged Navier–Stokes code MSU-TURBO . A low Reynolds number k- ε model was utilized to model turbulence. The rotor blade in question has a tip gap height of 2.1...

... 2011 21 07 2011 blades cooling flow visualisation mass transfer rotors stators turbulence vortices The efficiency of a gas turbine increases with the temperature of the hot combustion gases at the stage inlet. Modern gas turbines are designed to operate at turbine inlet...

... 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...

... of deterministic roughness is investigated in these experiments, varying the height and eccentricity of the roughness elements, showing the combined influence of roughness height and anisotropy of the rough surfaces on laminar to turbulent transition and the turbulent boundary layer as well as boundary layer...

... t tip gap height T temperature T 01 average inlet air temperature T w blade and endwall wall temperatures Tu turbulence intensity w g squealer rim width a absolute flow angle η film cooling effectiveness...

... , 126 , pp. 615 – 626 . 10.1115/1.1791287 Andrews , G. , Hussain , R. A. , and Mkpadi , M. , 2003 , “ Enhanced Impingement Heat Transfer: Comparison of Co-Flow and Cross-Flow With Rib Turbulators ,” Proceedings of the International Gas Turbine Congress , Paper No. IGTC2003Tokyo TS...

... levels of turbulence, which are typically found in sharp turns, in ribbed ducts, and, especially, in rotating ducts. In the past, a slip between motor and channel rotation causes additional non-negligible uncertainties during PIV measurements due to an unstable image position. These were caused...

... RANS applying a k - ε - v 2 - f turbulence model and the Spalart and Allmaras turbulence model and detached-eddy simulation (DES) based on the Spalart and Allmaras turbulence model are addressed to solve thermal convection. The CFD calculations were conducted by simulating a semicircular model...

...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...

... profile has a strong effect on the position of flow separation, whereby a hub-strong profile tends to separate at the casing and the tip-strong profile on the hub. Steady computational fluid dynamics (CFD) simulations using the shear stress transport (SST) turbulence model have been carried out based...

...E. L. Erickson; F. E. Ames; J. P. Bons Heat transfer distributions are experimentally acquired and reported for a vane with both a smooth and a realistically rough surface. Surface heat transfer is investigated over a range of turbulence levels (low (0.7%), grid (8.5%), aerocombustor (13.5...