Purpose

The purpose of this paper is to find the pressure and the knocking phenomena. To get the pressure values, the butterworth bandpass filter was used and the potential of knocking was found by using peak-to-peak pressure values and also the species concentration. Cooled exhaust gas recirculation was the method used to minimize the knocking occurrence in the engine. Moreover, the effect of premixed methanol and start of engine (SOI) on knocking were also determined.

Design/methodology/approach

This paper deals with the compression ignition engine to investigate the unfavorable knocking behavior. The tests were carried out with the 3D model of engine fueled with waste cooking oil blended with TiO2. A number of tests were taken to find the pressure variation and the species concentration at eight different locations in the computational model.

Findings

In doing the tests, the positive intended outcome was achieved. From results, it is clear that the SOI and premixed methanol mitigated the knocking process.

Originality/value

The species concentration and pressure in the form of filtered signal were proved to be the ideal methods for evaluating the knocking event in the engine.

中文翻译：

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以替代燃料混合物为燃料的活塞发动机的实验和数值模拟：CFD 方法

目的

本文的目的是找出压力和爆震现象。为了获得压力值，使用了巴特沃斯带通滤波器，并通过使用峰间压力值和物质浓度来发现爆震的可能性。冷却废气再循环是用于最大限度减少发动机爆震发生的方法。此外，还确定了预混甲醇和发动机启动 (SOI) 对爆震的影响。

设计/方法/方法

本文处理压燃式发动机以研究不利的爆震行为。使用混合了 TiO2 的废弃食用油作为燃料的发动机 3D 模型进行了测试。进行了许多测试以找到计算模型中八个不同位置的压力变化和物质浓度。

发现

在进行测试时，达到了积极的预期结果。从结果来看，很明显 SOI 和预混甲醇减轻了爆震过程。

原创性/价值

过滤信号形式的物质浓度和压力被证明是评估发动机爆震事件的理想方法。