Experimental Investigation and Regression Analysis on the Vibration and Noise Characteristics of an Unaltered Single-Cylinder Constant Speed CI Engine Using Various Biodiesels

The noise and vibrations stemming from combustion in a Compression Ignition (CI) engine directly affect end users. As a renewable energy source, there is potential for it to substitute diesel in CI engines. The present study seeks to explore the sound pressure level (SPL) and vibration characteristics of constant-rpm unaltered CI engines fueled with Nahar, Jatropha and Karanja biodiesel blends. The SPL and vibrations were recorded using, the B&K Photon+ portable measuring system with RTPro software, FFT Analyzer at varying loads and fuelled with diesel D100 and biodiesel blends BDN10, BDN20, BDN30, BDN40, BDN50, BDJ10, BDJ20, BDJ30, BDJ40, BDJ50, BDK10, BDK20, BDK30, BDK40 and BDK50 respectively. Regression analysis models, both linear and non-linear, were established to forecast the association among fuel characteristics and noise-vibration of engine, demonstrating excellent agreement. The findings indicate that, in general, the engine noise and vibration reduced with an increase in biodiesel blends up to 30%. Also, it is observed that for reducing the vibration and SPL of an engine, among all the considered parameters, the engine load is a significant parameter as compared to other parameters such as blending percentage. Furthermore, among the three biodiesels, Nahar is a more impactful biodiesel for reducing the engine’s vibration and noise.