Analysis of single phase fluid flow and heat transfer in slip flow regime by parallel implementation of Lattice Boltzmann method on GPUS

Çelik, Sıtkı Berat
In this thesis work fluid flow and heat transfer in two-dimensional microchannels are studied numerically. A computer code based on Lattice Boltzmann Method (LBM) is developed for this purpose. The code is written using MATLAB and Jacket software and has the important feature of being able to run parallel on Graphics Processing Units (GPUs). The code is used to simulate flow and heat transfer inside micro and macro channels. Obtained velocity profiles and Nusselt numbers are compared with the Navier-Stokes based analytical and numerical results available in the literature and good matches are observed. Slip velocity and temperature jump boundary conditions are used for the micro channel simulations with Knudsen number values covering the slip flow regime. Speed of the parallel version of the developed code running on GPUs is compared with that of the serial one running on CPU and for large enough meshes more than 14 times speedup is observed.


Simulation of conjugate heat transfer problems using least squares finite element method
Göktolga, Mustafa Uğur; Sert, Cüneyt; Department of Mechanical Engineering (2012)
In this thesis study, a least-squares finite element method (LSFEM) based conjugate heat transfer solver was developed. In the mentioned solver, fluid flow and heat transfer computations were performed separately. This means that the calculated velocity values in the flow calculation part were exported to the heat transfer part to be used in the convective part of the energy equation. Incompressible Navier-Stokes equations were used in the flow simulations. In conjugate heat transfer computations, it is req...
Improving flow structure and natural convection within fin spacings of plate fin heat sinks
Özet, Mehmet Erdem; Tarı, İlker; Department of Mechanical Engineering (2015)
The main objectives of this thesis are to numerically investigate the previously observed recirculation zones and longitudinal vortices that occur in low fin height plate finned horizontal heat sinks and to improve the flow structures and heat transfer in these zones using various approaches with the help of simulations performed using commercially available CFD software. The approaches used for improvements are replacing the outer most fins with higher ones, introducing gaps on the length of the fins in va...
3-D numerical simulations of fluid flow and heat transfer in various micro conduits
Turgay, Metin Bilgehan; Güvenç Yazıcıoğlu, Almıla; Department of Mechanical Engineering (2017)
In this work, it is aimed to investigate the effect of roughness geometrical properties and configurations on laminar flow and heat transfer characteristics in microchannels, numerically. For this purpose, two-dimensional parallel plate, and three-dimensional trapezoidal microchannels with different roughness properties are modeled along with the smooth ones. Fluid flow and heat transfer simulations are conducted with COMSOL Multiphysics. Roughness is modeled as triangular obstructions on one of the plates ...
Numerical simulation of fluid flow and heat transfer in a trapezoidal microchannel with COMSOL multiphysics: A case study
Turgay, Metin Bilgehan; Güvenç Yazıcıoğlu, Almıla (2018-01-01)
In this study, fluid flow and heat transfer in a trapezoidal microchannel are numerically investigated. For this purpose, a reference study with experimental and numerical solutions is adopted from the literature and solved with COMSOL multiphysics. Good agreement with the results of the reference work is obtained. In addition, effects of stabilization methods and element discretization options that are offered by the program on the results are investigated and discussed with examples. In addition, two diff...
Numerical and experimental analysis for comparison of square, cylindrical and plate fin arrays in external flow
İnci, Aykut Barış; Bayer, Özgür; Department of Mechanical Engineering (2018)
Geometrical optimization of square, cylindrical and plate fins for heat transfer augmentation is numerically performed in the external flow. Heat transfer performance of fins with different profiles are compared with same Reynolds number. The relation between the thermal characteristic of fins and boundary conditions like free-stream velocity and heat input are investigated. Experimental studies are performed using manufacturable fins to validate numerical model. Heat transfer correlations are derived in or...
Citation Formats
S. B. Çelik, “Analysis of single phase fluid flow and heat transfer in slip flow regime by parallel implementation of Lattice Boltzmann method on GPUS,” M.S. - Master of Science, Middle East Technical University, 2012.