采用同时双平面OH-LIF和立体PIV的PDKEEPAAA发动机内详细火焰传输的试验研究
An experimental study of the detailed flame transport in a SI engine using simultaneous dual-plane OH-LIF and stereoscopic PIV
摘要：
了解内燃机内火焰的详细传输过程对于预测点火、放热速率和评估发动机性能具有重要意义。这对于RANS和LES发动机模拟尤其重要，因为它们通常很难在不首先调整模型参数的情况下准确预测火焰传播和热释放。火焰传输的详细测量需要指导模型的开发。这项工作介绍了一个实验数据集，旨在研究详细的火焰传输和火焰/流动动力学SI发动机。同时双平面OH-LIF和立体PIV被用来获得未燃尽气体的速度，火焰位移速度和火焰的整体速度在火焰发展的早期三维测量。实验是在一个光学引擎中进行的，在800和1500 RPM与预混合的C8 H18-空气混合物。分析揭示了几种不同的火焰/流动配置，产生一个积极的或消极的火焰位移，火焰的反应物或产品的进展，分别。对于所使用的操作条件，Sd表现出与火焰曲率成反比的关系;观察到负Sd和凸火焰轮廓之间的强相关性。趋势是一致的热扩散火焰，但还没有量化的内燃机。在较高的RPM下，火焰扰动更严重，这使Sd分布向更高的正速度和负速度扩展。Ugas和Sd的空间分辨分布描述了缸内位置，其中对流或热扩散是促成火焰传输的主要机制。研究结果进行了讨论，在有关常见的发动机流的功能，包括固体表面附近的火焰传输。调查结果的目的是支持发动机模拟验证。
英文摘要：
Understanding the detailed flame transport in IC engines is important to predict ignition, rate of heat release and assess engine performance. This is particularly important for RANS and LES engine simulations, which often struggle to accurately predict flame propagation and heat release without first adjusting model parameters. Detailed measurements of flame transport are required to guide model development. This work introduces an experimental dataset designed to study the detailed flame transport and flame/flow dynamics for SI engines. Simultaneous dual-plane OH-LIF and stereoscopic PIV is used to acquire 3D measurements of unburnt gas velocity, flame displacement speed and overall flame velocity during the early flame development. Experiments are performed in an optical engine operating at 800 and 1500 RPM with premixed C8H18-air mixtures. Analysis reveals several distinctive flame/flow configurations that yield a positive or negative flame displacement for which the flame progresses towards the reactants or products, respectively. For the operating conditions utilized, Sd exhibits and inverse relationship with flame curvature; a strong correlation between negative Sd and convex flame contours is observed. Trends are consistent with thermo-diffusive flames, but have not been quantified in IC engines. Flame wrinkling is more severe at the higher RPM, which broadens Sd distribution towards higher positive and negative velocities. Spatially-resolved distributions of Ugas and Sd describe in-cylinder locations where convection or thermal diffusion is the dominating mechanism contributing to flame transport. Findings are discussed in relation to common engine flow features, including flame transport near solid surfaces. Findings are designed to support engine simulation validations.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
