使用格子博尔兹曼方法对发动机内的热浸泡进行数值调查
Zhenhai Gao1, Yang Yang1, Xingjun Hu2
1College of Automotive Engineering, Jilin University, Chang Chun, 130000, China.
Scientific reports
|August 22, 2024
概括
发动机关后的发动机热传递是使用空气热合研究的. 对流和辐射占主导地位,对流效率随着时间的推移而变化,这对于防止热损伤至关重要.
科学领域:
- 汽车工程 汽车工程
- 热管理 热管理
- 计算流体动力学的流体动力学.
背景情况:
- 关机后发动机中的高热积累会导致热损伤和敏感部件的疲劳.
- 了解发动机浸泡条件下的短暂热传递对于组件寿命至关重要.
研究的目的:
- 用空气热合方法研究在热浸泡条件下的发动机热传递.
- 分析主导的传热模式及其在关闭浸泡过程中的效率.
主要方法:
- 使用过渡计算流体动力学 (CFD) 软件,基于格子波兹曼法 (LBM).
- 采用空气热合方法来模拟SUV发动机模型中的热传递.
- 对模拟模型与实验数据进行了验证,以确保准确性.
主要成果:
- 交流和辐射是浸泡的最初120秒内主要的传热方式.
- 随着时间的推移,辐射效率下降,而对流效率波动,增加然后减少.
- 合方法准确地预测了发动机的热状态,冷却液和组件温度的误差很低.
结论:
- 开发的空气热合方法有效地预测了关键关闭浸泡期间的发动机热行为.
- 准确的热预测为设计冷却风扇控制策略提供了关键数据.
- 减轻热风险需要了解短暂的传热动态和组件灵敏度.
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