| 1. |
- Mirzaei, Maryam, 1982, et al.
(author)
-
Large Eddy Simulation of the flow and heat transfer in a half-corrugated channel with various wave amplitudes
- 2014
-
In: International Journal of Heat and Mass Transfer. - : Elsevier BV. - 0017-9310. ; 76, s. 432-446
-
Journal article (peer-reviewed)abstract
- Large Eddy Simulation (LES) of turbulent flow and convective heattransfer over a half-corrugated channel is presented in this paper. Simulationsare performed for various ranges of the normalized wave amplitudes,AM = 0 − 0.15 (the ratio of wave height to wave length). The Reynoldsnumber based on the bulk velocity is chosen as Reb = 10 000 and thePrandtl number is Pr=0.71. A comparison between the DNS and LESresults of a plane channel (AM = 0) at Re = 395 is also performed.The obtained results indicate that the region of recirculating flow dependsstrongly on the wave amplitude. This study shows that the Nusseltnumber (Nu) increases by increasing the wave amplitude until a specificvalue then it remains approximately constant. The thermal performanceparameter (JF) is used as a measure for the heat transfer enhancementrelative to the pressure drop and it is found that the maximum values ofNu and JF appear at AM = 0.1, which hence correspond to the optimumvalue of the wave amplitude.
|
|
| 2. |
- Mirzaei, Maryam, 1982, et al.
(author)
-
The effect of corrugation on heat transfer and pressure drop in channel flow with different Prandtl numbers
- 2013
-
In: International Journal of Heat and Mass Transfer. - : Elsevier BV. - 0017-9310. ; 66, s. 164-176
-
Journal article (peer-reviewed)abstract
- Large Eddy Simulation and Direct Numerical Simulation are applied to study the turbulent flow field in a wavy channel at two Prandtl numbers, Pr = 0.71 and Pr = 3.5, and Reynolds number Re b = 10,000. The characteristics of the separated shear layer and the near wall recirculating zone are discussed in relation to the turbulent heat transfer. Special attention is paid to the behavior of the flow and thermal boundary layers and various turbulent characteristics and their effects on the distribution of the Nusselt number and friction coefficient in the separation and reattachment regions. The results indicate that the thickness of the thermal boundary layer rather than the turbulent fluctuations has a significant effect on the local variation of the averaged Nusselt number. The results are compared with Direct Numerical Simulation results of a plane channel at the same Reynolds number. © 2013 Elsevier Ltd. All rights reserved.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Sohankar Esfahani, Ahmad, 1958, et al.
(author)
-
Erratum
- 2000
-
In: Journal of Fluids Engineering. ; 122:3, s. 643-
-
Journal article (peer-reviewed)
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Sohankar Esfahani, Ahmad, 1958
(author)
-
Numerical Study of Laminar, Transitional and Turbulent Flow Past Rectangular Cylinders
- 1998
-
Doctoral thesis (other academic/artistic)abstract
- The subject of flow past slender bluff bodies is of relevance to technical problems associated with energy conservation, structural design and acoustic emissions. The present work is restricted to an important sub-class of slender bluff body flow --- the incompressible flow around a stationary cylinder having a rectangular cross section, the cylinder being exposed to a constant free stream velocity. Time-dependent two- and three-dimensional (2D/3D-) numerical simulations are carried out. Some useful quantities such as the dominant wake frequency (the Strouhal number), mean and RMS values of drag and lift, and various surface pressures etc. were calculated for different Reynolds numbers. In 2D-simulations, the effects of cylinder side ratio (B/A, where B is the longest side) and flow incidence (.alpha.) were investigated. In these simulations an incompressible non-staggered arrangement SIMPLEC code was used. The QUICK and Van Leer schemes were used for the convective terms. The time discretization was implicit and a second-order Crank-Nicolson scheme was employed. The influence of Reynolds number (Re
|
|
