Computational modeling of fin-and-tube type vehicle radiators based on porous medium approach

Download
2014
Güler, Kadir Gökhan
A common tool for the determination of the thermal characteristics of fin-and-tube heat exchangers is the experimental testing. However, experimental testing is not feasible considering the cost and the labor-time. One alternative to the experimental testing is the utilization of computational fluid dynamics (CFD) analysis to predict the thermal characteristics of these kinds of radiators. However, CFD models are also not suitable to be used as a design tool since the considerably amount of computational power and the computational time required due to the complex geometric structures of the fins. This issue becomes problematic when the large-scale heavy-duty radiators are considered. Computational thermal performance analysis based on porous medium approach of a vehicle radiator is studied in this M.Sc. thesis. Fin side of the radiator is modeled as porous medium. Fluid flow and heat transfer characteristics are extracted from the unit cell fin domains and implementation is made into complete radiator assembly. Forchiemmer model is used for the porous medium characterization. Utilization of this modeling leads the way to obtain thermal and hydrodynamic characteristics of fin-tube type vehicle radiators.

Suggestions

Comparative Pyrolysis and Combustion Kinetics of Oil Shales
Kök, Mustafa Verşan (2000-02-01)
In this research, thermal characteristics and kinetic parameters of eight Turkish oil shale samples were determined by thermogravimetry (TG/DTG) at non-isothermal heating conditions both for pyrolysis and combustion processes. A general computer program was developed and the methods are compared with regard to their accuracy and the ease of interpretation of the kinetics of thermal decomposition. Activation energies of the samples were determined by five different methods and the results are discussed.
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...
Numerical simulation of turbine internal cooling and conjugate heat transfer problems with Rans based turbulance models
Görgülü, İlhan; Akmandor, İbrahim Sinan; Department of Aerospace Engineering (2012)
The present study considers the numerical simulation of the different flow characteristics involved in the conjugate heat transfer analysis of an internally cooled gas turbine blade. Conjugate simulations require full coupling of convective heat transfer in fluid regions to the heat diffusion in solid regions. Therefore, accurate prediction of heat transfer quantities on both external and internal surfaces has the uppermost importance and highly connected with the performance of the employed turbulence mode...
Modeling and sensitivity analysis of high temperature PEM fuel cells by using Comsol Multiphysics
Sezgin, Berna; Caglayan, Dilara Gulcin; DEVRİM, YILSER; Steenberg, Thomas; Eroğlu, İnci (2016-06-22)
The objective of this study is to observe the effect of the critical design parameters, velocities of inlet gases (hydrogen and air) and the conductivity of polymer membrane, on the performance of a high temperature PEM fuel cell. A consistent and systematic mathematical model is developed in order to study the effect of these parameters. The model is applied to an isothermal, steady state, three-dimensional PEM fuel cell in order to observe concentration profiles, current density profiles and polarization ...
Numerical investigation of bubbling fluidized bed to be used as high temperature thermal energy storage
Hiçdurmaz, Serdar; Tarı, İlker; Department of Mechanical Engineering (2017)
A thermal energy storage unit designed to be used in a solid particle concentrated solar energy system is analysed with the help of a commercial Computational Fluid Dynamics tool. Hydrodynamics of the bubbling fluidized sand bed of which dimensions are 0.28 m x 1 m x 0.025 m to be used as direct contact heat exchanger are modelled and validated. Geldart B type particles with diameter of 275 micron and density of 2500 kg/m3 are used in modelling of bubbling fludized sand bed. Syamlal O’Brien drag model with ...
Citation Formats
K. G. Güler, “Computational modeling of fin-and-tube type vehicle radiators based on porous medium approach,” M.S. - Master of Science, Middle East Technical University, 2014.