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Jojoba bio-diesel is one of the most promising bio-fuels to replace gas oil in diesel engines. Therefore, the main object of the present work was to measure and correlate the pressure rise ignition delay of jojoba bio-diesel and its blends with gas oil behind incident shock waves in a shock tube. For this purpose, a shock tube test set up was designed and manufactured. It was fully instrumented for delay measurement with two piezo-electric pressure transducers, dual mode charge amplifier, data acquisition card and a computer with suitable LabVIEW software. The test variables included the type of fuel (percentage of Jojoba bio-diesel in the blend with gas oil), equivalence ratio, ignition temperature and ignition pressure. It was found that jojoba bio-diesel exhibited a lower ignition delay in comparison with that of gas oil. Rich or lean mixtures produce long delays, whilst the minimum delay occurred near the stoichiometric mixture.

The main aim of this work was to study knock, pre-ignition, performance and emissions of an alternative novel jojoba bio-gasoline fuel using a Ricardo E6/MS variable compression ratio spark ignition engine. It was fuelled by different blends of jojoba bio-gasoline and gasoline with an octane of 90. The results gave the effect of equivalence ratio, speed, ignition timing, compression ratio, inlet air pressure and temperature using different blends on detonation, pre-ignition, performance and emissions. The results were correlated to give the designer an access to the tool needed for developing an existing engine or in the design of a new engine.

A study on the effect of induction manifold angles in tumble induced turbulence on detonation and pre-ignition in spark-ignition engines was conducted on a Ricardo E6 variable compression engine. A new cylinder head was designed and manufactured with four induction manifold inserts with angles of 30°, 40°, 50° and 60° in addition to the original angle of 90°. The onset of pre-ignition and detonation were defined by a piezo-electric pressure transducer. Knock was characterized by the “knock-limited compression ratio” concept. However pre-ignition was characterized by the input electrical power consumed by a pre-igniter acting as an artificial hot spot. A set of experiments were carried out on each induction manifold to cover the effect of the design and operating parameters of the engine on detonation and pre-ignition.