Pressuri̇zed ai̇r dryer heat recovery uni̇t heat exchanger desi̇gn and cfd analysi̇s


Thesis Type: Postgraduate

Institution Of The Thesis: Uludağ Üniversitesi, Turkey

Approval Date: 2013

Thesis Language: Turkish

Student: AYŞE BURCU YILDIZ

Supervisor: MUHSİN KILIÇ

Abstract:

In this study, the fluid flow and heat transfer inside the Plate-Fin compact heat exchanger passages with the small hydraulic diameters are investigated numerically. In the three dimensional numerical analysis, both laminar and turbulent flows are considered. Turbulent flow is modeled with the RNG k- model with the enhanced wall treatment and the Shear Stress Transport (SST) k- model with a low-Reynolds-number correlation. Heat conduction in the fin and convection in the fluid are analyzed simultaneously as a three dimensional conjugate problem. Various duct aspect ratios from 2 to 8 are considered with a wide range of Reynolds numbers from 500 to 5000. The friction coefficients and Nusselt numbers in the developing region for these passages are obtained, which can be used in estimation of heat transfer performance in plate-fin compact heat exchangers. Obtained numerical results are validated with the experimental data taken from the literature. It is shown that the numerical results obtained by the use of the SST k- model with a low-Reynolds-number correlation shows a good agreement with the experimental data over whole the Reynolds number range considered in this study.