ABSTRACTThere is an increasing demand of studying abrasive wear of internal combustion engines caused by sand particles to meet the severe working conditions in Arab countries represented in the high ambient dust concentrations. Sand covers more than 95 % of the land and the warm desert regions are characterized by sudden fluctuations in wind speed and temperature seasonally. Airborne contaminant levels are particularly high and the maximum concentration measured was approximately 1.0 milligram per cubic meter. During severe storm conditions dust concentrations of the order of 100 to 500 times higher may be encountered. In the present work, wear particles, retained by oil filter of an internal combustion engine working in El-Minia Governorate, were examined by optical microscope to reveal details of size, shape and quantity of particles. It was detected the generation of large severe wear particles that signal the imminent failure of wearing surface. Particles in the form of loops, spirals, and bent wires were generated, where increase in the number and size of these particles showed that an abrasive wear mechanism is progressing rapidly. Sand particles of different size in relatively high concentration were detected. Based on this observation, it can be concluded that the prevailing mode of wear was abrasion. Based on the results of the present work, it is necessary to develop the oil, air and fuel filters. Besides, proper selection of oil additives will improve the performance of the engine through decreasing both friction and wear. The recommended type of oil additives is that of polar molecules that can adhere to the sand particles and sliding surfaces to decrease abrasion action of sand particles.
Ali et al. (Fri,) studied this question.