Knock and Pre-Ignition in Spark-Ignition Engine Fuelled by Different Blends of Jojoba Bio-Gasoline with Kerosene 2019-01-5046
In the present article, the knock tendency and pre-ignition resistance (PIR) were determined experimentally for different blends of kerosene and jojoba bio-gasoline. The effects of varying equivalence ratios, rotational speed, inlet air temperature and pressure, and ignition timing on knock tendency and PIR were investigated. The influence of compression ratio on PIR was also studied. Jojoba bio-gasoline was synthesized using transesterification method through performing a chemical reaction between well-stirred jojoba raw oil and alcohol. Experiments were carried out on a Ricardo E6/MS variable compression ratio spark-ignition (SI) engine fuelled by jojoba bio-gasoline/kerosene blends of volumetric percentages of 0%, 5%, 10%, 15%, and 20% jojoba bio-gasoline. The onset of pre-ignition and knock were detected by observing the pressure oscillations using a piezoelectric pressure transducer, a synchronizing magnetic sensor, and a degree-marking probe. The results showed that increasing the percentage of bio-gasoline in the blends with kerosene leads to a significant increase in PIR and a remarkable decrease in the knock tendency. This will lead to the design of a more efficient engine by increasing its compression ratio when fuelled by jojoba bio-gasoline. Analytical correlations were developed to assess the knock tendency and PIR for different fuel blends taking into consideration the various design and operating variables.