Measurement of engine vibrations using fuel blends of recycled vegetable oil and diesel – a mathematical and computational analysis

Abstract

Vibrations of the internal combustion engine are an indicator of its stability and mechanical condition. The vibrations of the engine resulting from reciprocating and rotating movement of its parts also depend on quality of combustion process and properties of the fuel. The present research focuses on the effect of the properties and concentration of the fuel blend of diesel and recycled vegetable oil on the vibration level of the engine due to the combustion process. The vibrations of the engine were collected with accelerometers of a mobile communication device, to then determine the resulting vibration level of the engine and its frequency spectrum by means of fast Fourier transforms. In this procedure carried out with each of the tested fuels, the properties such as the cetane number and the flash point were found as those that have influence on the vibration level of the engine. The purpose of the present investigation is to quantify the level of vibration produced by different concentrations of the fuel blend of diesel and recycled vegetable oil, depending on their properties and compared to pure diesel. From this, it is concluded that the stability of the engine in regard to its level of vibration due to the combustion process, can be controlled according to the properties of the fuel.