Zenkin E. Methods for system design-analytical and bench diagnosis of automobiles

The object of investigation is the process of diagnosing of the automobile diesel engine with common rail. The aim of the thesis investigation is the development of an urgent method of common rail automobile engines diagnosing. The following methods of investigation have been applied in the given work: mathematical, physical and simulation modeling, applied at urgent diagnosing method grounding of automobile diesel engines with common rail. The method of material balance of fuel is used at grounding and choice of parameters that serve as an information basis for diagnosing. The methods of stand tests are used at failures modeling in the common rail. The digital methods of output logging and processing are applied at experimental investigations. There has been developed a common computer-integrated informational environment that includes the following items: a mathematical model, L Card L 783 or UsbOScilloscope 2 data collection modules, a Powergraph applied programs package, KTS 520 system scanner, Esitronic structured database. The practical value of the results obtained consists in the following - the mathematical model developed allows calculating the normative values of fuel pressure and determine the fuel pressure at simulation of system's elements' technical condition change. There has been developed a computer-integrated toolbox, on computer basis, of the mathematical model developed, and soft hardware that create a common information environment. The results of the investigation obtained by means of calculations, physical modeling of processes in the hydro accumulator on the stand and diesel engines testing on vehicles compose a structured database. The theoretical and practical value of the given work consists in the following-there has been obtained a formula representing the dependence of tractive effort on vehicle's wheels from diesel engine common rail elements' technical condition; there has been obtained a result that reveals the fact that at failures occurrence the rate of pressure increase in the common rail system grows slower and the reaction of the control system in the form of pulse ratio changes. The scientific novelty of the given work consists in the following fact-the tractive effort on vehicle's wheels for the first time is expressed by means of common rail hydraulic parameters. the dependence of particular signal sections of the standard pressure meter and actuating pulse duty factor on the fuel pressure adjuster from the technical condition of the common rail elements is determined for the first time.The results obtained are implemented at the state-run enterprise "Kharkiv Propulsion Engineering Design Office" as well as in the studying process of KhNAHU at students training on specialty 7.0922058 "Automobiles and Automotive Fleet", the method and the equipment developed for urgent diagnosing of automobile diesel engines are implemented and applied at "Dizelservis" service station ( " Tais " LTD) Kharkiv.