Piston Design For A Highly-intensified Diesel Engine

As the important part of the diesel’s energy transforming from chemical tomechanical, piston plays as the force transferring, heat transferring, sealing and guidingroles. Piston is working under cyclic varied thermal load and mechanical load. Withthe development and application of new technology and new materials, high speed, highpressure and high speed diesels have been becoming the development trend. Diesel’sconsolidation have become higher and higher, and the piston’s challenge is that the loadexceeds the limit of structure capacity and working temperature. High temperatureperformance materials and reasonable structure is the key to meet the dieselrequirement.A domestic diesel design institute is now executing a new generation dieselresearch of highly intensified diesel technology, and Hunan Jiangbin Piston Corpundertake its piston research task of this engine. In this paper,based on the background of a research project, design and manufacture of strengtheneddiesel engine piston, according to highly-intensified requirements about the dieselengine. The following is the main contents of the paper.(1) According to the given engine parameters and parts of the piston dimensions,based on the technical of Jiangbin, we determined to use the company’s new M03Al-Sipiston material, and treat piston top surface with anodic oxidation, cast withwear-resistant ring in the first ring groove, and with inner cooling gallery.(2) first design piston structure such as piston head structure, wear-resistant ring,cavity, fire bank, groove etc. This paper designs the cooling gallery, determines thegallery shape and position, then designs piston outline, determine the cross-section atdifferent heights and its diameter, designs piston conical outline shape, designs pistonpin boss and pin hole, determines the pin hole section line shape.(3) Through FEA analysis of thermal load, mechanical load and coupling analysis,optimizate the internal cooling gallery structure by comparing the structure scheme ofdifferent cooling gallery analysis. Pin hole profile was determined by analysis of threekinds of pin hole structure contrast; Determined the piston outline scheme analyzingabout the thermal and mechanical load coupling and kinematics. (4) Through piston thermal fatigue test, the rationality of the anodic oxidation ontop surface is determined. Through the piston pin hole fatigue test, the best outlineshape of the pin hole is selected. Through the piston skirt pressure test, capability tosatisfy the skirt structure requirement of the two piston materials M02and M03isevaluated.(5) Pistons are manufactured as the optimal design. After engine running test, nocrack phenomenon had been found on the piston surface of the combustion chamber,piston pin hole, and outer circle. The wear traces on piston pin hole and outer circle isbasically normal, and piston have met the design target requirements.