摘要
同轴射流用于向炉窑中同时注入燃料和氧化剂,因其混合效率高、内外层流量精确可控、火焰稳定等优点,被广泛应用于有色金属冶炼的炉窑加热。为深入理解和掌握富氧条件下碳氢燃料同轴射流的掺混机制,基于数值仿真系统研究了超音速同轴射流和亚音速同轴射流的流动、传热和传质特性。结果表明,超音速同轴射流显著增加了富氧空气和甲烷的掺混能力,中心流道和外围流道的气相掺混位置更靠近上游。此外,超音速同轴射流有更强的引射作用,从中心管喷出的气体处于过膨胀状态,会在出口处发生压缩,导致静压和密度阶跃上升,速度和马赫数阶跃下降。最后,相同的质量流量下,由于更强的剪切作用,超音速同轴射流的轴向穿透距离相比传统射流略有减小。研究结果在一定程度上揭示了超音速同轴射流和常规同轴射流的差异,为同类喷枪的设计提供参考。
Coaxial jets are used to inject both fuel and oxidants into furnaces,offering advantages such as high mixing efficiency,precise control of inner and outer flow rates,and flame stability,making them widely used in heating furnaces for non-ferrous metal smelting.To better understand the mixing mechanism of hydrocarbon fuels under oxygen-enriched conditions,the flow,heat transfer,and mass transfer characteristics of both supersonic and subsonic coaxial jets were systematically investigated based on numerical simulation system.The results indicate that the supersonic coaxial jet significantly enhances the mixing capability of oxygen-enriched air and methane,with the gas-phase mixing region between the central and outer streams occurring further upstream.Additionally,the supersonic coaxial jet exhibits a stronger entrainment effect,where the gas from the central channel is in an overexpanded state,undergoing compression at the outlet,resulting in a stepwise increase in static pressure and density,and a decrease in velocity and Mach number.Finally,at the same mass flow rate,the axial penetration distance of the supersonic coaxial jet is slightly reduced compared to conventional jets due to stronger shear effects.This study provides insights into the differences between supersonic and conventional coaxial jets,offering guidance for the design of similar lances.
作者
彭文贵
杨世亮
阳坤林
胡建杭
PENG Wengui;YANG Shiliang;YANG Kunlin;HU Jianhang(School of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China)
出处
《有色金属(冶炼部分)》
北大核心
2025年第8期175-183,共9页
Nonferrous Metals(Extractive Metallurgy)
基金
云南省重大科技专项计划项目(202302AQ370001)。
关键词
同轴射流
超音速
数值仿真
掺混效果
可压缩特性
coaxial jet
supersonic
numerical simulation
mixing efficiency
compressible properties
作者简介
彭文贵(1997-),男,硕士研究生;通信作者:杨世亮(1986-),男,教授。
