Evaluation of vibration and noise characteristics of a compression-ignition engine fuelled with natural gas-biodiesel dual fuel

Abstract

As environmental requirements become more stringent and the planet becomes more polluted, the replacement of conventional diesel is attracting more interest. In order to use alternative fuels, such as biodiesel and natural gas, their effects must be examined not only in terms of the engine's environmental indicators but also in terms of engine vibrations and sound pressure. This study examined influence of dual fuel – biodiesel and natural gas on the vibrations and sound pressure of a compression ignition engine. Conventional diesel (D) or Hydrotreated vegetable oil biodiesel (HVO) was used as a pilot fuel for gas ignition. Gaseous fuel was natural gas (NG), which was injected into the intake manifold changing energy share of the gaseous fuel (40%, 60% and 80%). Tests performed at a constant engine crankshaft speed and fixed start of pilot fuel injection 6° BTDC, while fuel composition and engine load was changed. This experiment revealed correlations between gas energy share in liquid fuel and ecological and energy indicators of the compression-ignition engine.