Numerical study on injection of flue gas as a heat carrier into coal reservoir to enhance CBM recovery

Abstract To investigate the operational problems of the composite heat carrier generator (CHCG) in actual industrial applications such as overheating and poor safety performance, an integrated analytical model was established. For this model, the commercial software Fluent was first applied to simulate the gas-liquid turbulent flow, diesel vaporization and combustion, and the mixing process between the flue gas and the preheated water. Taking the parameters obtained from the Fluent model as the boundary condition, an indirect contact heat transfer model considering the heat transfer between the hot flue gas and the cold water has been solved. Based on this model, the areas where the phenomena of overheating and high thermal stress are prone to occur have been determined, and the size of the water sleeve has been redesigned.

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Numerical Simulations of Turbulent Mixing and Autoignition of Hydrogen Fuel at Reheat Combustor Operating Conditions

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2011-46264 ◽

2011 ◽

Cited By ~ 1

Author(s):

Elizaveta Ivanova ◽

Berthold Noll ◽

Peter Griebel ◽

Manfred Aigner ◽

Khawar Syed

Keyword(s):

Natural Gas ◽

Numerical Simulations ◽

Flue Gas ◽

Turbulent Mixing ◽

Turbulence Modeling ◽

Numerical Study ◽

Operating Conditions ◽

Fuel Blend ◽

Flow Configuration ◽

Modeling Methods

Turbulent mixing and autoignition of H2-rich fuels at relevant reheat combustor operating conditions are investigated in the present numerical study. The flow configuration under consideration is a fuel jet perpendicularly injected into a crossflow of hot flue gas (T > 1000K, p = 15bar). Based on the results of the experimental study for the same flow configuration and operating conditions two different fuel blends are chosen for the numerical simulations. The first fuel blend is a H2/natural gas/N2 mixture at which no autoignition events were observed in the experiments. The second fuel blend is a H2/N2 mixture at which autoignition in the mixing section occurred. First, the non-reacting flow simulations are performed for the H2/natural gas/N2 mixture in order to compare the accuracy of different turbulence modeling methods. Here the steady-state Reynolds-averaged Navier-Stokes (RANS) as well as the unsteady scale-adaptive simulation (SAS) turbulence modeling methods are applied. The velocity fields obtained in both simulations are directly validated against experimental data. The SAS method shows better agreement with the experimental results. In the second part of the present work the autoignition of the H2/N2 mixture is numerically studied using the 9-species 21-steps reaction mechanism of O’Conaire et al. [1]. As in the reference experiments, autoignition can be observed in the simulations. Influences of the turbulence modeling as well as of the hot flue gas temperature are investigated. The onset and the propagation of the ignition kernels are studied based on the SAS modeling results. The obtained numerical results are discussed and compared with data from experimental autoignition studies.

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Experimental and Numerical Study on Vapor Condensation of Wet Flue Gas in Chimney

Diffusion in Solids and Liquids III - Defect and Diffusion Forum ◽

10.4028/3-908451-51-5.119 ◽

2008 ◽

pp. 119-125

Author(s):

Nijaz Delalić ◽

Ejub Džaferović ◽

Ejub Ganić

Keyword(s):

Flue Gas ◽

Numerical Study ◽

Vapor Condensation

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Effect of Guide Vane Shape on Duct Flow Characteristics in a Flue-Gas Desulfurization System : A Numerical Study

Transactions of the Korean Society of Mechanical Engineers B ◽

10.3795/ksme-b.2018.42.3.243 ◽

2018 ◽

Vol 42 (3) ◽

pp. 243-250

Author(s):

Hyeong Rae Kim ◽

In Sik Hwang ◽

Sang Shin Park ◽

Jee Eun Min ◽

Jungho Hwang

Keyword(s):

Flue Gas ◽

Numerical Study ◽

Guide Vane ◽

Flow Characteristics ◽

Flue Gas Desulfurization ◽

Duct Flow ◽

System A

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Numerical study on operating characteristics of self-driven total heat recovery system for wet-hot flue gas

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2020.115223 ◽

2020 ◽

Vol 173 ◽

pp. 115223 ◽

Cited By ~ 2

Author(s):

Chenghu Zhang ◽

Yujie Yang ◽

Lijia Fan ◽

Xinpeng Huang

Keyword(s):

Flue Gas ◽

Heat Recovery ◽

Numerical Study ◽

Total Heat ◽

Operating Characteristics ◽

Recovery System ◽

Heat Recovery System

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Numerical Study of Transport Membrane Condenser Heat Exchangers

Volume 8: Heat Transfer and Thermal Engineering ◽

10.1115/imece2016-67882 ◽

2016 ◽

Author(s):

Esmaiil Ghasemisahebi ◽

Soheil Soleimanikutanaei ◽

Cheng-Xian Lin ◽

Dexin Wang

Keyword(s):

Flue Gas ◽

Heat Exchangers ◽

Ceramic Membrane ◽

Waste Heat ◽

Numerical Study ◽

Tube Bundle ◽

Pure Water ◽

Separation Mechanism ◽

Low Grade ◽

Water Recovery

In this study tube bundle Transport Membrane Condenser (TMC) has been studied numerically. The tube walls of TMC based heat exchangers are made of a nano-porous material and has a high membrane selectivity which is able to extract condensate pure water from the flue gas in the presence of other non-condensable gases (i.e. CO2, O2 and N2). Low grade waste heat and water recovery using ceramic membrane, based on separation mechanism, is a promising technology which helps to increase the efficiency of boilers and gas or coal combustors. The effects of inclination angles of tube bundle, different flue gas velocities, and the mass flow rate of water and gas flue have been studied numerically on heat transfer, pressure drop and condensation rates. To assess the capability of single stage TMC heat exchangers in terms of waste heat and water recovery at various inlet conditions, a single phase multi-component model is used. ANSYS-FLUENT is used to simulate the heat and mass transfer inside TMC heat exchangers. The condensation model and related source/sink terms are implemented in the computational setups using appropriate User Defined Functions (UDFs).

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