PERFORMANCE STUDY OF INTERNAL COMBUSTION ENGINE USING NANO MATERIALS IN THE LUBRICANT

Abstract

The lubricant is essential for the smooth working and desired performance of tribopairs. In the applications like internal combustion engine where the tribopairs have to operate in adverse tribological condition like high speed, high temperature, high range of operating temperature, long oil changing intervals etc., the use of proper lubricant becomes critical and essential. The improper lubrication in an I.C. engine may be hazardous for environment moreover it reduces the service life of the tribopairs. The lubricant used for modern-day I.C. engine cannot be plain mineral oil or synthetic oil. A lot of performance booster additives have been used to enhance the physical and chemical stability along with tribological and thermal performance the lubricant. The lubricants nowadays are blended up to 25% with such lubricant additives. The nanoparticles have proved to be very promising lubricant additives as they possess unique physical, chemical, thermal and tribological properties. Such particles can be used as a lubricant additive to enhance overall the performance of the lubricant. In the present work, attempts have been made to study the tribological performance of the 15W40 lubricating oil in the presence of various nanoparticles. The stable nanolubricant with various compositions of the nanoparticles have been prepared and investigated for stability by Zeta potential test. The zeta potential values for the nanolubricant ranges from 24 mV to 45 mV which indicate moderate to high stability The tribological analysis of the nanolubricant was conducted on the pin on disc tribometer according to ASTM G-99. The coefficient of friction and specific wear rate in presence of nanolubricant has been compared with the fresh 15W40 lubricant for both fully flooded and starved lubrication conditions. The nanolubricant decreased the C.O.F. significantly moreover the S.W.R. in case of nanolubricant was negligible as compared to fresh 15W40. The tribological and extreme pressure analysis of the nanolubricant had also been conducted on the four ball tester according to ASTM D4172 and ASTM Din 51350-02, the wear scar diameter was measured by the vision inspection system at 300 X magnification. The C.O.F. decreased upto 25% and WSD decreased upto 59% in case of nanolubricant. The weld load for the nanolubricant increased upto 29%. ` vi

The novel nanolubricants had been synthesized by combination of two nanoparticles and tested for the tribological performance on both pin on disc tribometer and four ball tester, performed better than the fresh 15W40. The novel nanolubricants were used in the internal combustion engine for the performance analysis and emission analysis. The BSFC decreased and BTE increased significantly in presence of nanolubricant. The engine emission also decreased in presence of nanolubricant.