Numerical simulation and research on the effect of the classification of gas composition on the heat process of gas radiation tubes
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摘要: 采用現有的雙P型輻射管進行燃燒實驗，并進行相應的CFD仿真對比，結果顯示NOx體積分數的數值計算與試驗結果誤差最大為3.6%，其他參數的偏差均在1%以內.將空氣分級的理念應用于雙P型輻射管，設計一種帶支管的分區分級燃氣輻射管，并對其流動和傳熱特性進行仿真研究.結果表明：支管通入空氣量占總空氣量的25%時，輻射管壁面溫差最大，熱效率最高；支管通入燃氣量為20%時，輻射管壁面溫差最小，壁面溫度均勻性最好；支管以相同空燃比同時通入空氣和燃氣，且支管通入空燃氣量為總燃氣量的25%時，整個輻射管內氣體溫度分布最均勻；支管通入空燃氣量占總氣體量從5%增加到35%的過程中，壁面溫差先降低后緩慢增加，支管通入燃氣量為20%時輻射管壁面溫差最小.Abstract: The combustion experiment of an existing double P type radiant tube and the corresponding CFD simulation were performed in this paper. By contrast, the maximum error of NOx concentration between numerical calculation and experimental data is 3.6%, and the deviation of the other parameters is less than 1%. Then the concept of air classification was applied to the double P type radiation tube to design a belt pipe nozzle hierarchical gas-fired radiant tube. The flow and heat transfer characteristics were studied. The results show that when air into the branch pipe accounts for 25% of the total amount of air, the radiant tube wall temperature and thermal efficiency are the highest. When the content of gas into the branch is 20%, the radiation tube wall temperature realizes the minimization and the uniformity of wall temperature is the best. When both air and gas at the same air-fuel ratio are introduced into the branch pipe, and the volume of air and fuel gas is 25% of the total amount of gas, the gas temperature distribution in the radiant tube is the most uniform. When the volume of air and fuel gas into the branch pipe increases from 5% to 35%, the wall surface temperature decreases first and then increases slowly; when it is 20%, the radiation tube wall temperature reaches a minimum.
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Key words:
- combustion /
- gas fired radiant tubes /
- air-fuel ratio /
- model validation /
- nitrogen oxide control
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參考文獻
[1] Ahanj M D, Rahimi M, Alsairafi A A. CFD modeling of a radiant tube heater. Int Commun Heat Mass Transfer, 2012, 39(3):432 [2] Tsioumanis N, Brammer J G, Hubert J. Flow processes in a radiant tube burner:isothermal flow. Fuel, 2008, 87(1):103 [3] Tsioumanis N, Brammer J G, Hubert J. Flow processes in a radiant tube burner:combusting flow. Energy Convers Manage, 2011, 52(7):2667 [6] Shen J, Liu J X, Zhang H, et al. NOx emission characteristics of superfine pulverized anthracite coal in air-staged combustion. Energy Convers Manage, 2013, 74:454 [7] Saleh H E. Effect of exhaust gas recirculation on diesel engine nitrogen oxide reduction operating with jojoba methyl ester. Renewable Energy, 2009, 34(10):2178 [10] Saravanan P, Sahoo G, Srikanth S, et al. Failure analysis of radiant tube burners in continuous annealing line (CAL) of an integrated steel plant. J Fail Anal Prev, 2010, 11(3):286 [11] Irfan M, Chapman W. Thermal stress in radiant tubes:a comparison between recuperative and regenerative systems. Appl Therm Eng, 2010, 30(2):196 [12] Irfan M A, Chapman W. Thermal stresses in radiant tubes due to axial, circumferential and radiant temperature distributions. Appl Therm Eng, 2009, 29(10):1913 [14] Normann F, Andersson K, Leckner B, et al. High-temperature reduction of nitrogen oxides in oxy-fuel combustion. Fuel, 2008, 87(17):3579 [16] Quinn E D. Radiant Tube with Recirculation:US Patent, US7959431.2011-06-14 -
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