A valve that was supposed to be open, to allow the heat and steam to escape, was closed.
一个本应打开的阀门被关上了，这个阀门控制着热量和蒸汽的泻出。
2
He continues a long-standing artistic tradition of imagining the end of civilization, a form of emotional and spiritual escapevalve operated since man found a means to express himself.
他长期以来保持着对文明终结的艺术性想象，这是一种情感和精神的宣泄形式，并以此表达自我。
3
Since cordite burns at a greater rate at a higher pressure a relief valve must be used to allow generated gas to escape to atmosphere at times when the demand is low.