Strongly Heated Turbulent Flow in a Channel with Pin Fins

• Published in: Energies (Basel) Vol. 16; no. 3; p. 1215
• Main Authors: Lee, Chien-Shing, Shih, Tom I. -P., Bryden, Kenneth Mark, Dalton, Richard P., Dennis, Richard A.
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2023
• Subjects: Anisotropy; Cooling; Design and construction; Direct numerical simulation; Fluid dynamics; Fluid flow; Gas turbines; Heat conductivity; heat loads; Heat transfer; Heating load; internal cooling; Kinetic energy; Large eddy simulation; LES; Load; Mathematical models; pin fin; Pin fins; Reynolds number; Scale models; Subgrid scale models; Temperature; Turbine blades; Turbines; Turbulence; Turbulence models; Turbulent flow; Velocity; Viscosity; Wall jets; United States
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en16031215

Large-eddy simulations (LES) were performed to study the turbulent flow in a channel of height H with a staggered array of pin fins with diameter D = H/2 as a function of heating loads that are relevant to the cooling of turbine blades and vanes. The following three heating loads were investigated—wall-to-coolant temperatures of Tw/Tc = 1.01, 2.0, and 4.0—where the Reynolds number at the channel inlet was 10,000 and the back pressure at the channel outlet was 1 bar. For the LES, two different subgrid-scale models—the dynamic kinetic energy model (DKEM) and the wall-adapting local eddy-viscosity model (WALE)—were examined and compared. This study was validated by comparing with data from direct numerical simulation and experimental measurements. The results obtained show high heating loads to create wall jets next to all heated surfaces that significantly alter the structure of the turbulent flow. Results generated on effects of heat loads on the mean and fluctuating components of velocity and temperature, turbulent kinetic energy, the anisotropy of the Reynolds stresses, and velocity-temperature correlations can be used to improve existing RANS models.