ANALYSES, DEVELOPMENT AND CONSTRUCTION OF ENGINES

Keywords: medium speed marine diesel engines, performance, comparative analysis, dimensional ranges.

Based on preliminary analysis, the need for the development of marine engine dimensional ranges is substantiated. Dimensional ranges are demonstrated as a solid basis of industrial sector development. They play important role in progress of domestic engine building. Core principles of dimensional range calculation are formulated, and appropriate design procedure is offered.

Keywords: internal combustion engine, valve springs, spring coil vibration, mathematical model, experimental study, high-speed filming.

A method of valve spring strength analysis is presented, as applied to VAZ car engine. A mathematical model of valve gear dynamics is developed. The results are presented of spring coil tests for vibration with high-speed filming.

Keywords: locomotive engines, boost, thermal stresses in piston, thermal insulating coatings.

The work in question was targeted at reduction of thermal stress in engine piston. This was achieved through application of corundum thermal insulating coating to combustion chamber surfaces, and intensification of heat removal from piston crown. The above measures enabled to enhance engine output by up to 25%, which required no changes in core construction materials.

Keywords: gas engine, combustion, pre-chamber flame ignition, optimization of pre-chamber geometry.

The article presents the results of investigation targeted at enhancement of fuel economy and reliability of RUMO gas engine type 8GCHN22/28 featuring pre-chamber flame ignition. Flame energy characteristics and combustion curves are shown as functions of pre-chamber geometry and settings. Recommendations are offered on organization of efficient low-emission combustion in gas engine.

ENGINE SYSTEMS AND UNITS

Keywords: reciprocating internal combustion engine, suction, turbocharging, flow fluctuation, suction system improvement.

Instantaneous values of air velocity, static pressure and local heat-transfer factor in suction channel a single-cylinder experimental electric speed were analyzed as functions of engine speed. A method is offered to mitigate flow pulsation in engine suction system through relief of excessive air pressure downstream of a turbocharger. Stabilization of air flow in suction channel contributes into smoother operation of multi-cylinder engine, lower noise level, longer service life and higher compressor efficiency.

AUTOMATION AND DIAGNISTICS

Keywords: heavy duty rock haulers, fuel injection system, ultrasonic monitoring, intelligent control system.

The article discusses some issues concerning fuel injection system ultrasonic monitoring in engines powering heavy duty rock haulers. Output data of the monitoring system are being used in design of intelligent control system, which enables optimization of engine operation modes in terms of fuel saving.

ENVIRONMENTAL ISSUES

Keywords: UNECE Rules Nr. 49-05, ESC ˜ European Stationary Test Cycle, ˜˜˜ ˜ European Transitional Test Cycle, lowering the emissions from diesel engines.

The results are presented of a research completed by JSC KamAZ targeted at the development of competitive on-road cars meeting international safety standards. The research was carried out in the framework of ˜Strategy of Russian Federation Automotive Industry Development for the Period up to Year 2020˜. Better environmental performance of KamAZ engines was achieved due to improvement in combustion arrangement and use of SCR technology. Engines in question passed certification stand tests using test cycles ESC and ETC according to UNECE Rules Nr. 49-05.

MAINTENANCE AND REPAIR ISSUES

Keywords: marine propulsion engine, low-load operation, switching off cylinders/cycles, fuel economy, displacement control.

Expected improvement in fuel economy of marine engine type 12DN23/30 (40DM) was evaluated using ˜specific work vs. speed˜ curves. Engine fuel economy under low loads may be improved through switching off part of cylinders. Fuel consumption under low loads may thus be reduced by up to 18%.

ENGINE BUILDING NEWS

Keywords: dual fuel engines, knock, techniques for detection and control.

The paper presents knock detection algorithms based on signals from cylinder pressure and vibration sensors. In both cases knock cycles are identified based on comparison of the individual cycle knock indicator level with a constant threshold or on a statistical approach. In this work two different categories of knock- detection methods, based both on frequency domain manipulations of the cylinder pressure signal and on cylinder head vibration analysis, were extensively compared through an experimental investigation carried out on a Wartsila W50DF engine.