Вестник Научно-исследовательского института железнодорожного транспорта (Apr 2023)
Improvement of the air supply system for diesel locomotives
Abstract
Introduction. The diesel air supply system is designed to increase the air supply to the piston part of the engine, which increases its power. The system includes a supercharging unit (turbocharger) and an aftercooler. As their connection with the piston part is gas-air, this limits the range of feasible operation of the diesel engine. In recent years, the development of the air supply system, which is contributed to the improvement of the fuel efficiency of the diesel engine, is aimed at increasing the turbocharger efficiency and expanding its feasible operation range. The article proposes a new way of improving the fuel efficiency of diesel locomotives: control of two supercharging units (registered supercharging) by successively switching on each for diesel operation in each of the two power modes — below and above average power.Materials and methods. A diagram of the diesel engine air supply with a registered supercharging system is given, and a method for graph-analytical computation of the combined operation of supercharging units with the piston part of the engine is given.Results. The authors substantiated and selected ways of increasing the fuel efficiency of diesel locomotives in operation by improving the characteristics of the air supply system at modes below average power. The calculation and experimental method gave an estimate of the increase in the fuel efficiency of a 2TE25K diesel locomotive equipped with a diesel engine with a registered supercharging system, compared with a standard 21-26DG diesel generator.Discussion and conclusion. The practice of creating, researching and implementing registered supercharging systems at JSC Kolomensky Zavod and abroad shows that, despite the complexity of the design, such systems give a significant increase in the efficiency of the propulsion system in operation. It is recommended to check the characteristics of a diesel locomotive with the proposed registered air supply system on a bench diesel generator, followed by an operational check on a diesel locomotive.
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