本文件概述了EGR冷却器的使用方式和原因，定义了常用术语，讨论了设计问题和权衡，并确定了常见故障模式。将选择性冷却的废气重新引入燃烧室只是内燃（IC）发动机（包括柴油和汽油）排放控制策略的一个组成部分，有助于减少氮氧化物（NOx）的排气口排放。简要介绍了减少NOx排气口排放的其他方法，但超出了本文件的范围。

This document provides an overview on how and why EGR coolers are utilized, defines commonly used nomenclature, discusses design issues and trade-offs, and identifies common failure modes. The reintroduction of selectively cooled exhaust gas into the combustion chamber is just one component of the emission control strategy for internal combustion (IC) engines, both diesel and gasoline, and is useful in reducing exhaust port emission of nitrogen oxides (NOx). Other means of reducing NOx exhaust port emissions are briefly mentioned, but beyond the scope of this document.