n.倒灌风，下向通风，向下气流...

downdraft的音标：downdraft的英式发音音标为：['daʊndrɑ:ft]downdraft的美式发音音标为：['daʊnˌdrɑft]...

倒焰...

downdraf的音标：downdraf的英式发音音标为：['daʊndrɑ:f]downdraf的美式发音音标为：['daʊndrɑf]...

Ventilation: positive downdraft exhaust ventilation should be provided to maintain vapor concentration below TLV.通风: 为了使气体聚集程度维持在阀极限值之下,应提供通畅的向下棋流排气通风设施.Beijing Cherokee engine uses Cart YFA carburetor which is single ba...