[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-109-1-fire-science-007":3},{"subject":4,"subjectSlug":5,"subjectKicker":6,"subjectShort":7,"question":8,"related":27,"sameNumber":52,"hasEssay":26},"火災學概要","fire-science","火災學 · Fire Science","火災學",{"id":9,"webId":10,"year":11,"session":12,"subject":4,"number":13,"stem":14,"options":15,"answer":20,"answerNote":21,"images":22,"imagesPending":23,"lawTimestamp":11,"explanation":24,"explanationDeep":25,"freq":12,"indexable":26},"fire-109-1-火災學概要-007","fire-109-1-fire-science-007",109,1,7,"進入石化工廠，車輛會被要求在排氣管加裝滅焰器（flame arrester）以避免火災爆炸之發生，加裝該措施防制火災爆炸之原理為：",{"A":16,"B":17,"C":18,"D":19},"窒息","冷卻","抑制連鎖反應","阻止擴展","B",null,[],false,"本題考點：滅焰器(flame arrester)阻火的作用機制，對應四大滅火原理中的冷卻(淬熄)。\n【正解理由】滅焰器由多層金屬網或密集的細窄流道構成，孔隙尺寸小於該可燃氣體的淬熄距離。火焰欲通過時，燃燒反應區的熱量被大面積金屬迅速傳導帶走，反應區溫度降到無法維持鏈鎖傳播的程度，火焰便在通過前熄滅，可燃氣體仍可通行而火焰不得穿越。其本質是吸熱降溫，屬冷卻作用，故選 B。\n【逐項排除】\n(A) 窒息是降低氧濃度或隔絕空氣供應；滅焰器的孔隙讓氣體照常通過，並未改變混合氣的氧含量，不屬窒息。\n(B) 金屬網把火焰的熱大量吸走，使反應區溫度低於維持燃燒所需，正是冷卻(淬熄)原理，為應選項。\n(C) 抑制連鎖反應是靠鹵素或乾粉的負觸媒捕捉 H·、OH· 自由基，屬化學滅火；滅焰器不含任何化學藥劑，純為物理熱傳。\n(D) 阻止火焰擴展是加裝滅焰器要達成的結果，不是滅火原理本身；四大原理為冷卻、窒息、除去可燃物與抑制連鎖反應，並無「阻止擴展」一項。\n【記憶點】滅焰器＝金屬網把火焰的熱吸走，冷到燒不下去，靠冷卻不是靠隔絕。","滅焰器的理論基礎是淬熄距離。可燃性混合氣的火焰在狹窄通道中傳播時，反應區產生的熱有一部分被管壁帶走；當通道尺寸小到某個臨界值，散熱速率超過產熱速率，火焰便無法維持而熄滅，這個臨界尺寸即淬熄距離。淬熄距離與最小點火能量正相關：氫氣、乙炔的淬熄距離極小(約 0.6 mm 以下),故其滅焰器孔隙必須做得比甲烷、丙烷用的更細密。\n常見構造分為金屬網式、皺摺板(波紋帶)式與砂礫、多孔陶瓷填充式，共同點都是以極大的比表面積換取高熱傳導速率。應用場所包括石化廠區進出車輛的排氣管、儲槽的通氣口與呼吸閥、可燃氣體管線、油氣回收系統與火炬設備。裝在排氣管的用意很直接：引擎排氣可能挾帶火星或高溫碳粒，一旦廠區空氣中已有可燃性蒸氣，火星逸出即可能點燃並回火，滅焰器把火焰擋在管內，是典型的預防性防爆措施。\n易混淆概念對照：滅焰器阻擋的是爆燃(deflagration)等次音速火焰；若管線內已發展成爆轟(detonation)等超音速壓力波，一般型式擋不住，需用耐爆轟型。與滅焰器常被並列的還有阻火閥、防火阻絕器與礦工安全燈——戴維燈正是最早利用金屬網淬熄原理的裝置，原理與本題完全相同。要特別分清楚的是，滅焰器阻擋的是火焰在管線或容器口的傳播，防火門、防火閘門阻擋的則是建築空間之間的延燒，兩者的尺度與手段完全不同。\n四大滅火原理的代表配對也是高頻考點：冷卻對應水與滅焰器的熱傳導、窒息對應二氧化碳與惰性氣體、除去可燃物對應關閉燃料閥與防火間隔、抑制連鎖反應對應海龍、鹵化烴與乾粉。判別題只要問「機制」而非「效果」,就要回到這四格作答。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-109-1-fire-science-006","某次閃電的過程中，雲的底部和地面之間，電壓高達 1 千萬伏特，並在約 0.02 秒內輸送 20 庫倫的電量至地面。下列與閃電有關的敘述何者正確？",6,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-109-1-fire-science-008","1 度電為 1,000 瓦．小時（1 kWh），試問 1 度電約等同多少千卡（kcal）？",8,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-109-1-fire-science-005","下列有關二氧化碳（CO2）滅火劑之敘述，何者錯誤？",5,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-109-1-fire-science-010","有水之場所的插頭應加裝何種裝置以防止感電發生？",10,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-109-1-fire-science-004","某一火災成長至 2,000 kW 所需時間為 400 秒，請問該火災屬何種成長性火災？[Q：釋熱率（MW）； 1\u002F2 t：經過時間（sec）；k：火災成長常數（sec\u002FMW ）]",4,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-109-1-fire-science-011","某一線徑 2.0 m\u002Fm 之電線 1 km 長之電阻值為 5.657 Ω，熱阻抗為 378。若周遭溫度為 20℃，當此 10 cm 長之電線通過 10 安培時，其芯線溫度（℃）約為多少？",11,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-114-1-fire-science-007",114,"油類火災沸溢（Boilover）與濺溢（Spilover）現象之發生區別，下列何者錯誤？",{"webId":58,"year":59,"stem":60,"number":13},"fire-113-1-fire-science-007",113,"依公共危險物品及可燃性高壓氣體製造儲存處理場所設置標準暨安全管理辦法，第四類公共危險物品對於易燃液體定義，是指在一大氣壓時，閃火點在攝氏幾度以下之液體？",{"webId":62,"year":63,"stem":64,"number":13},"fire-112-1-fire-science-007",112,"高壓氣體之爆炸界限，通常較常壓下為廣，下列何者氣體之爆炸界限，會呈現加壓時上、下限初呈狹窄，但繼續加壓後又變廣的現象？",{"webId":66,"year":67,"stem":68,"number":13},"fire-111-1-fire-science-007",111,"油類火災為何種火災？",{"webId":70,"year":71,"stem":72,"number":13},"fire-110-1-fire-science-007",110,"己烷在閃火點時的飽和蒸氣壓為 9.12 mmHg，根據 Burgess-Wheeler 定理其燃燒熱約為多少 kcal\u002Fmole？",1785129967232]