Abstract In spark ignition (SI) engines, knock suppression is essential to improve fuel economy. Integrating new technologies into already complex downsized turbocharged engines increases the number of design and control variables substantially and requires extensive engine testing. Utilizing simulation-based study in an engine development process is crucial to reduce expensive and time-consuming engine tests. A quasi-dimensional (quasi-D) two-zone SI engine model is typically used in SI engine simulations. However, the usefulness of quasi-D-based simulation tools is often limited by the predictive capability of knock models. In this study, a novel knock model intended to be implemented in quasi-D SI engine simulation was developed. The model comprises a two-stage ignition delay model, a knock combustion model, and a knock index model. The knock model simulates the heat release spike during a knock combustion, which can be observed from the apparent heat release rate generated with the low-pass filtered cylinder pressure data. The model was calibrated and validated against engine experimental data. Its capability of knock detection and knock-limited spark timing estimation was demonstrated under various conditions of octane numbers, air–fuel equivalence ratios, and coolant temperatures with toluene primary reference fuel (TRPF). The knock model was also able to capture different knock characteristics between TPRF and primary reference fuel (PRF) in modern downsized turbocharged SI engines. The proposed methodology represents a useful tool to be employed during the development phase of an engine to reduce the experimental efforts while improving the engine performance at knock borderline.

中文翻译：

---

使用点火延迟和爆震燃烧建模的准维 SI 燃烧模拟中的爆震检测

摘要 在火花点火 (SI) 发动机中，爆震抑制对于提高燃油经济性至关重要。将新技术集成到已经很复杂的小型涡轮增压发动机中会显着增加设计和控制变量的数量，并且需要进行大量的发动机测试。在发动机开发过程中利用基于仿真的研究对于减少昂贵且耗时的发动机测试至关重要。SI 发动机模拟通常使用准维（准 D）两区 SI 发动机模型。然而，基于准 D 的仿真工具的实用性通常受到爆震模型预测能力的限制。在这项研究中，开发了一种旨在在准 D SI 发动机仿真中实施的新型爆震模型。该模型包括两阶段点火延迟模型、爆震燃烧模型和爆震指数模型。爆震模型模拟爆震燃烧期间的放热峰值，这可以从低通滤波气缸压力数据产生的表观放热率中观察到。该模型根据发动机实验数据进行了校准和验证。在辛烷值、空燃当量比和使用甲苯主要参考燃料 (TRPF) 的冷却剂温度的各种条件下，证明了其爆震检测和爆震限制点火正时估计的能力。爆震模型还能够捕捉现代小型涡轮增压 SI 发动机中 TPRF 和主要参考燃料 (PRF) 之间的不同爆震特性。