The heavy rain this morning was caused by an unstable and moist airstream . more than 100 millimetres of rainfall were recorded over the northern part of hong kong island , kowloon , tseung kwan o and sai kung . the rain was heaviest in kwun tong and clear water bay where more than 200 millimetres of rainfall were registered 今天早上的暴雨源于一股不稳定潮湿气流，主要集中在港岛北部、九龙、将军澳及西贡一带，为该区带来超过100毫米雨量，其中官塘及清水湾雨势最大，雨量超过200毫米。
While the speed is very large , the fuel - air mixing behind the airstream is decreased and the span that the fuel flow in the second combustor is reduced , so the combustion efficiency is decreased , h ) if the fuel streams impinge with the airstreams directly at the air - inlet exit , it make against increasing the combustion efficiency , i ) increasing air - to - fuel ratio within proper range can increase the combustion efficiency 增加燃气喷射速度有利于增强回流区强度，头部燃烧温度上升，但速度太大则会减弱燃气同空气在进气道下游的掺混燃烧，减少燃气在室内停留时间，燃烧效率降低； 8燃气射流与空气流在进气道出口直接撞击不利于燃烧效率的提高； 9在适当范围内增大空燃比能显著提高燃烧效率。
