Investigation of radiative heat transfer in freeboard of a 0.3 MWt AFBC test rig

Kozan, M
Selçuk, Nevin
Based on the analysis of measured data on flow rates, concentrations and temperatures taken during steady state operation of a lignite-fired 0.3 MWt Atmospheric Fluidized Bed Combustor (AFBC) test rig, radiative exchange in freeboard of the combustor was modeled by using a well-stirred enclosure model in conjunction with Radiosity-Irradiation Method (RIM). Radiative properties of the particle laden combustion gases were calculated by assuming grey radiation behaviour for both particles and gas, and using Leckner's correlations for gas and Mie theory for particles. The accuracy of the model was tested by comparing its predictions with incident radiative heat fluxes measured on the freeboard wall. Comparisons between the incident radiative heat fluxes predicted by the present model and those measured show that this engineering approach can be used with confidence by designers for the particle loadings typically encountered in freeboards of bubbling fluidized bed combustors.


On the performance of curvature stabilization time stepping methods for double-diffusive natural convection flows in the presence of magnetic field
Cibik, Aytekin; Eroglu, Fatma G.; Kaya Merdan, Songül (Springer Science and Business Media LLC, 2021-01-01)
© 2021, Springer Science+Business Media, LLC, part of Springer Nature.This paper considers analytically and numerically the curvature-based stabilization method for double-diffusive natural convection flows in the presence of magnetic field. Unconditionally stable and optimally accurate second-order approximations are obtained. The impact of curvature stabilization on different flow fields are presented for several numerical test problems.
Cyclic crack growth behaviour of two nickel base turbine disc alloys
Arslan, G; Doruk, M (1998-05-15)
The high temperature fatigue crack growth behaviour of the nickel base superalloys Alloy 718 and Rene 95 (specimen thickness = 4.1 mm) were investigated and compared with each other. Fatigue crack propagation (FCP) tests were carried out in laboratory air at room temperature and 600 degrees C by using C-T (compact tension) type specimen that were fatigue precracked at room temperature.
Computational investigation of flow through a louvered inlet configuration
Tuncer, İsmail Hakkı (2001-01-01)
Viscous, subsonic flows through a flush louvered inlet configuration without inlet vanes are investigated using the overflow Navier-Stokes solver with overset grids. The variation of the mass flow rate through the engine intake as a function of intake pressure is assessed. The computed results show that the flow distortion and the pressure loss in the plenum chamber are significant, yet a sufficient amount of mass flow rate may be obtained at the expense of total pressure recovery.
A fast model for computing infrared atmospheric background effects
Sivaslıgil, Mustafa; Esendemir, Akif; Department of Physics (2006)
The infrared atmospheric background modeling can be considered as one of the important key factor to develop a successful target detection technique. During the infrared atmospheric background modeling, defining the input parameters of the atmospheric profile are very important for the calculations of the absorption, emission and scattering effects of the atmosphere. The main objective of this thesis is to find the answer for the question أis it possible to determine the أeffectiveؤ height range for the sea...
Analytical and numerical solutions to rotating orthotropic disk problems
Kaya, Yasemin; Eraslan, Ahmet Nedim; Department of Engineering Sciences (2007)
Analytical and numerical models are developed to investigate the effect of orthotropy on the stress distribution in variable thickness solid and annular rotating disks. The plastic treatment is based on Hill’s quadratic yield criterion, total deformation theory, and Swift’s hardening law. The elastic-plastic stress distributions, residual stresses and radial displacement distributions are obtained after having analysed the cases of rotating solid disk, annular disk with rigid inclusion, annular disk subject...
Citation Formats
M. Kozan and N. Selçuk, “Investigation of radiative heat transfer in freeboard of a 0.3 MWt AFBC test rig,” COMBUSTION SCIENCE AND TECHNOLOGY, pp. 113–126, 2000, Accessed: 00, 2020. [Online]. Available: