Technical solution for evaluation of contact stiffness and strength of the joint surfaces of injector

Abstract

The quality of the engine work, service-life time, compliance with the environmental standards and requirements depends on workability of the injector. The normal operation of mentioned structure as a whole depends on the contact strength, stiffness and workability of its joint surfaces (different connections which can be related to conditionally fixed). A technical solution was proposed for evaluation the contact stiffness and strength of the joint surfaces of the engine injector based on the existing technology of injector fabrication and physical-mathematical model of elastoplastic contacts developed by the authors. The authors found that the work of the engine as a whole depends on the characteristics of the contacting surfaces of the injector, especially the microgeometry parameters of the rough layer, real contact area, ductility, physical-mechanical properties of the materials of the contact pair and loading conditions. A technical solution has been developed allowing to increase the contact stiffness of the contact joints of injector for fuel uniform distribution in the diesel combustion chamber by 1.2–1.5 times. This solution is based on the author’s study and complex analysis for given geometric dimensions of the injector and operation conditions of internal combustion engine. Thus, the solution proposed by the authors has shown its efficiency and can be recommended for application in the internal combustion engines including ship engines.