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Title: Energy and exergy balance in the process of pulverized coal combustion in a tubular combustor

Abstract

A theoretical model of exergy balance, based on availability transfer and flow availability, in the process of pulverized coal combustion in a tubular air-coal combustor has been developed to evaluate the total thermodynamic irreversibility and second law efficiency of the process at various operating conditions. The velocity, temperature, and concentration fields required for the evaluation of flow availability have been computed numerically from a two-phase separated flow model on a Eulerian-Lagrangian frame in the process of combustion of pulverized coal particles in air. The total thermodynamic irreversibility in the process has been determined from the difference in the flow availability at the inlet and outlet of the combustor. A comparative picture of the variations of combustion efficiency and second law efficiency at different operating conditions, such as inlet pressure and temperature of air total air flow rate and inlet air swirl, initial mean particle diameter, and length of the combustor, has been provided to shed light on the trade-off between the effectiveness of combustion and the lost work in the process of pulverized coal combustion in a tubular combustor.

Authors:
; ;  [1]
  1. Indian Institute of Technology, Kharagpur (India)
Publication Date:
OSTI Identifier:
20712188
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Heat Transfer; Journal Volume: 127; Journal Issue: 12
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; EXERGY; COMBUSTION; COAL; PULVERIZED FUELS; HEAT TRANSFER; THERMODYNAMICS; TWO-PHASE FLOW; MATHEMATICAL MODELS; PARAMETRIC ANALYSIS; ENERGY BALANCE

Citation Formats

Som, S.K., Mondal, S.S., and Dash, S.K.. Energy and exergy balance in the process of pulverized coal combustion in a tubular combustor. United States: N. p., 2005. Web. doi:10.1115/1.2101860.
Som, S.K., Mondal, S.S., & Dash, S.K.. Energy and exergy balance in the process of pulverized coal combustion in a tubular combustor. United States. doi:10.1115/1.2101860.
Som, S.K., Mondal, S.S., and Dash, S.K.. Thu . "Energy and exergy balance in the process of pulverized coal combustion in a tubular combustor". United States. doi:10.1115/1.2101860.
@article{osti_20712188,
title = {Energy and exergy balance in the process of pulverized coal combustion in a tubular combustor},
author = {Som, S.K. and Mondal, S.S. and Dash, S.K.},
abstractNote = {A theoretical model of exergy balance, based on availability transfer and flow availability, in the process of pulverized coal combustion in a tubular air-coal combustor has been developed to evaluate the total thermodynamic irreversibility and second law efficiency of the process at various operating conditions. The velocity, temperature, and concentration fields required for the evaluation of flow availability have been computed numerically from a two-phase separated flow model on a Eulerian-Lagrangian frame in the process of combustion of pulverized coal particles in air. The total thermodynamic irreversibility in the process has been determined from the difference in the flow availability at the inlet and outlet of the combustor. A comparative picture of the variations of combustion efficiency and second law efficiency at different operating conditions, such as inlet pressure and temperature of air total air flow rate and inlet air swirl, initial mean particle diameter, and length of the combustor, has been provided to shed light on the trade-off between the effectiveness of combustion and the lost work in the process of pulverized coal combustion in a tubular combustor.},
doi = {10.1115/1.2101860},
journal = {Journal of Heat Transfer},
number = 12,
volume = 127,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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