雅思小作文流程圖解析及范文:蒸汽的生產(chǎn)

　　Task：The production of steam using a gas cooled nuclear reactor.

 

　　思路解析：

　　1. 看懂基本過(guò)程和原理，定位流程的起點(diǎn)和終點(diǎn)。

　　2. 按照箭頭依次進(jìn)行描述，不能出現(xiàn)順序顛倒，或是過(guò)程缺失。

　　3. 圖中的文字提示應(yīng)加入到描述之中。

　　4. 分段原則：流程圖基本不分段，一個(gè)主體段包含所有過(guò)程，但請(qǐng)注意過(guò)程之間的連接詞，eg,首先，然后，接下來(lái)，最后。

　　參考范文：

　　The process of how a gas-cooled nuclear reactor works consists of the reactor itself and a heat exchanger.

　　The reactor contains uranium fuel elements which are surrounded by graphite moderators and topped by charge tubes for loading fuel elements, and boron control rods. The whole reactor is contained in a pressure vessel surrounded by a concrete shield.

　　From the reactor the hot gas flows through a duct into the heat exchanger which is outside the concrete radiation shielding. In the heat exchanger, steam is generated in a secondary loop. There a pipe brings in water which is heated to steam, and this then flows out to the turbo-alternator. Meanwhile the hot gas sinks to the bottom of the heat exchanger and passes through a gas blower which pushes it into a cool gas duct and back to the reactor.

　　As can be seen, this is a continuous cycle that keeps the reactor from overheating, while carrying away the heat and steam, which will power the turbines.

　　(166 words)