Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Influence of gray particle assumption on the predictive accuracy of gas property approximations
Date
2018-11-01
Author
Ates, CİHAN
Selçuk, Nevin
Külah, Görkem
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
215
views
0
downloads
Cite This
In this study, influence of gray particle assumption on the predictive accuracy of gas property models is investigated for conditions typically encountered in industrial coal-fired furnaces. The aim is (i) to identify how the share of gas radiation is influenced by the presence of particles and particle properties and (ii) to determine the effect of gray particle assumption on the predictive accuracy of gas property approximations. For that purpose, predictive accuracy of a simple gas property model is benchmarked against that of Spectral Line-Based Weighted Sum of Grey Gases Model (SLW) in the presence of gray/non-gray particles with different ash compositions, particle loads and boundary conditions. Input data required for the radiation code and its validation are provided from two combustion tests previously carried out in a 300 kWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig burning low calorific value Turkish lignite with high volatile matter/fixed carbon (VM/FC) ratio in its own ash. Comparisons reveal that gray particle assumption leads to over-estimation of particle radiation, which leads to under-estimation of gas radiation share in total radiative heat exchange. This under-estimation is found to be reflected on the predictive accuracy of gas property models, that is, a simple gas property model can be found to be "accurate" if particles are assumed to be gray although that is not the case. Furthermore, share of particle radiation in total radiative heat exchange is demonstrated to be strongly dependent on the spectral nature of particle properties. The results show that accurate gas property models such as SLW are needed to represent the spectral behavior of combustion gases even at high particle loads.
Subject Keywords
Radiative heat transfer
,
Combustion
,
Gas radiation
,
SLW
,
Non-gray particle radiation
,
Ash particles
URI
https://hdl.handle.net/11511/30608
Journal
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
DOI
https://doi.org/10.1016/j.jqsrt.2018.09.010
Collections
Graduate School of Natural and Applied Sciences, Article
Suggestions
OpenMETU
Core
Assessment of SLW-1 model in the presence of gray and non-gray particles
Özen, Guzide; ATEŞ, CİHAN; Selçuk, Nevin; Külah, Görkem (2019-02-01)
In this study, predictive accuracy of Gray Gas and SLW-1 approximations is benchmarked against Spectral Line-Based Weighted Sum of Grey Gases Model (SLW) in multidimensional enclosures involving gray/non-gray absorbing, emitting and scattering particles. Input data required for the radiation code and its validation are provided from two combustion tests previously carried out in a 300 kWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig burning low calorific value Turkish lignite with high vola...
Influence of fly ash composition on non-gray particle radiation in combusting systems
Ates, CİHAN; Selçuk, Nevin; Külah, Görkem (2018-08-01)
In this study, chemical composition dependency of both radiative properties of ash particles and radiative heat exchange are investigated for conditions typically encountered in industrial coal-fired furnaces. For that purpose, chemical composition dependent / independent complex index of refraction models are utilized to evaluate (i) spectral particle absorption efficiencies, scattering efficiencies and asymmetry factors, (ii) particle cloud properties representing pulverized coal fired furnaces (PC-Fired)...
Significance of particle concentration distribution on radiative heat transfer in circulating fluidized bed combustors
Ates, CİHAN; Selçuk, Nevin; Külah, Görkem (2018-02-01)
In this study, effect of particle concentration distribution on radiative heat transfer in circulating fluidized bed combustors (CFBCs) is investigated. The aim is to identify how important it is to include axial and radial variations of particle concentration along the splash and dilute zones in radiative heat transfer calculations and to determine the predictive accuracy of simple OD and 1D approximations for particle concentration distribution in the riser by benchmarking their predictions against a semi...
Influence of spectral particle properties on radiative heat transfer in optically thin and thick media of fluidized bed combustors
Ates, Cihan; Sen, Ozge; Selçuk, Nevin; Külah, Görkem (2017-12-01)
In this study, influence of spectral particle properties on radiative heat transfer in the freeboard/dilute zone of fluidized bed combustors (FBCs) is investigated. The aim is to identify how important it is to involve spectral particle properties and to determine the predictive accuracy of gray Mie and gray Geometric Optics (GOA) approximations in optically thin and thick media by benchmarking their predictions against spectral solutions. For that purpose, input data required for modelling radiative heat t...
Influence of soot on radiative heat transfer in bubbling fluidized bed combustors
Yaşar, Mehmet Soner; Selçuk, Nevin; Külah, Görkem (2021-08-01)
The effect of soot particles and aggregates on radiative heat transfer in bubbling fluidized bed combustors is investigated. For this purpose, a soot radiative property model based on Rayleigh scattering theory is coupled with in-house developed 1-D gray and spectral radiation codes and a 3-D spectral radiation code based on method of lines solution of discrete ordinates method for the application of (i) a 1-D slab problem involving combustion gases and soot and (ii) freeboard of a 0.3 MWt atmospheric bubbl...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
C. Ates, N. Selçuk, and G. Külah, “Influence of gray particle assumption on the predictive accuracy of gas property approximations,”
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
, pp. 67–83, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30608.