在高温和高压下添加水对层状预混合乙醇/空气火焰的影响
Linlin Yang1, Xiaohang Fang1,2, Felix Leach1
1Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, U.K.
概括
在乙醇/空气火焰中,添加水显著降低了层层燃烧速度 (LBV),特别是在富含燃料的条件下. 对于水性乙醇LBV的新相关性提高了在高温和高压下的精度.
科学领域:
- 燃烧科学 燃烧科学
- 化学工程是化学工程的重要组成部分.
- 热力学是一种热力学.
背景情况:
- 了解乙醇燃烧对于优化发动机性能至关重要.
- 现有的层状燃烧速度 (LBV) 相对关系在特定条件下显示出差异.
研究的目的:
- 在升高的条件下,数量研究添加水对乙醇/空气火焰的影响.
- 为含水乙醇/空气混合物开发一种新的,优化的LBV相关性.
主要方法:
- 高含水量的乙醇/空气火焰的数值模拟.
- 使用恒定体积方法进行实验数据分析.
- 开发和验证一个新的LBV相关性.
主要成果:
- 结合高阶和交叉项的新LBV相关性显示性能有所改善,特别是在富含燃料的混合物中.
- 相关性准确地预测了LBV在广泛的温度和压力范围内.
- 添加水主要通过稀释来降低LBV,化学和热物理影响较小.
结论:
- 开发的LBV相关性在与发动机相关的条件下对水性乙醇/空气混合物有效.
- 对于富含燃料,含水量高的混合物,需要进一步精制化学机制.
- 添加水对火焰温度和释放热量的速度有重大影响,特别是在富含燃料的火焰中.
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