大连理工大学学报
大連理工大學學報
대련리공대학학보
JOURNAL OF DALIAN UNIVERSITY OF TECHNOLOGY
2014年
1期
37-42
,共6页
抑爆%有限速率燃烧模型%火焰熄灭%幂律模型
抑爆%有限速率燃燒模型%火燄熄滅%冪律模型
억폭%유한속솔연소모형%화염식멸%멱률모형
explosion suppression%finite rate combustion model%frame extinguish%power-law model
基于流体动力学和燃烧理论,建立了管道直径为500 mm的瓦斯爆炸数学模型,借助Fluent流体力学软件,采用有限速率燃烧模型,对管道内甲烷预混气体爆炸后被惰性气体熄灭的过程进行了数值模拟研究,考察了瓦斯被点燃后,喷入不同流量高压、低温二氧化碳气体后管道内的燃烧流场特性。结果表明,二氧化碳喷入量低于12 kg/s不能使管内火焰熄灭;二氧化碳喷入量大于16 kg/s时,能大大降低管道内混合气体温度,同时降低甲烷和氧气浓度,导致火焰在二氧化碳喷入口所在管道截面处熄灭。此过程中管内最大反应速率降低过程可分为3个阶段,其中2个快速降低阶段均符合幂律模型。二氧化碳喷入量在16~100 kg/s时,火焰熄灭时间先迅速变短后变化缓慢;模拟结果与试验结果吻合较好。研究结果可为煤矿防爆抑爆研究工作提供理论依据和参考,同时对保障煤矿安全生产和人民生命安全也具有重要的现实意义。
基于流體動力學和燃燒理論,建立瞭管道直徑為500 mm的瓦斯爆炸數學模型,藉助Fluent流體力學軟件,採用有限速率燃燒模型,對管道內甲烷預混氣體爆炸後被惰性氣體熄滅的過程進行瞭數值模擬研究,攷察瞭瓦斯被點燃後,噴入不同流量高壓、低溫二氧化碳氣體後管道內的燃燒流場特性。結果錶明,二氧化碳噴入量低于12 kg/s不能使管內火燄熄滅;二氧化碳噴入量大于16 kg/s時,能大大降低管道內混閤氣體溫度,同時降低甲烷和氧氣濃度,導緻火燄在二氧化碳噴入口所在管道截麵處熄滅。此過程中管內最大反應速率降低過程可分為3箇階段,其中2箇快速降低階段均符閤冪律模型。二氧化碳噴入量在16~100 kg/s時,火燄熄滅時間先迅速變短後變化緩慢;模擬結果與試驗結果吻閤較好。研究結果可為煤礦防爆抑爆研究工作提供理論依據和參攷,同時對保障煤礦安全生產和人民生命安全也具有重要的現實意義。
기우류체동역학화연소이론,건립료관도직경위500 mm적와사폭작수학모형,차조Fluent류체역학연건,채용유한속솔연소모형,대관도내갑완예혼기체폭작후피타성기체식멸적과정진행료수치모의연구,고찰료와사피점연후,분입불동류량고압、저온이양화탄기체후관도내적연소류장특성。결과표명,이양화탄분입량저우12 kg/s불능사관내화염식멸;이양화탄분입량대우16 kg/s시,능대대강저관도내혼합기체온도,동시강저갑완화양기농도,도치화염재이양화탄분입구소재관도절면처식멸。차과정중관내최대반응속솔강저과정가분위3개계단,기중2개쾌속강저계단균부합멱률모형。이양화탄분입량재16~100 kg/s시,화염식멸시간선신속변단후변화완만;모의결과여시험결과문합교호。연구결과가위매광방폭억폭연구공작제공이론의거화삼고,동시대보장매광안전생산화인민생명안전야구유중요적현실의의。
Based on the theory of fluid dynamics and combustion , the mathematical model of gas explosion in the pipe with diameter of 500 mm is established ,by Fluent ,numerical simulation study of the flame′s quenching process in inert gas is conducted by using the finite rate combustion model , and the characteristics of explosion field by injecting different flow rate of high pressure and low temperature CO2 are also investigated .T he experimental results show that ,w hen the CO2 injection is less than 12 kg/s ,it can not extinguish the flame in the pipe ;however ,when the CO2 injection is greater than 16 kg/s ,it can greatly reduce the temperature of the mixed gas ,and also dilute the methane and oxygen ,and eventually lead to the flame extinguished at the carbon dioxide entrance . The reducing process of the maximum reaction rate can be divided into three stages ,where two of the high-speed reducing stages satisfy the power-law model .When the CO2 injection is between 16 kg/s and 100 kg/s ,the extinction time reduces rapidly ,and then changes slowly ;the simulation results agree well with the experimental data .Research results can provide theoretical basis and reference for the explosion suppression in coal mine ,and also have practical significance to protect the safety of people′s lives during coal mine production .