Keywords: diesel engines, mechanical losses, mechanical losses pressure, lube oil temperature, regression analysis, empirical dependence.

According to our analysis, calculated trends for mechanical losses in diesel engines need certain refinement. This may be achieved through the use of regression equation taking account of friction pressure as a function of lube oil temperature. Calculated values vs. test results for various engine types are presented.

Keywords: reciprocating engine, fuel injection, boil-off, flame shape, fuel superheat degree, spray valve.

The research in question concerns atomization of boiling liquid jet discharged from a short nozzle. The authors offer a fuel injection method for diesel engines based on boil-off effect, when fuel flame shape may be tuned up through varying fuel superheat degree and length of injector axial channel.

Keywords: diesel engines, heavy fuel, noxious emissions, cavitation fracture of a drop, gasification of sprayed fuel.

A new technology of enhancement of heavy fuel combustion is offered, that draws on cavitation phenomenon. Experiments demonstrated that sprayed heavy fuel may be gasified through the use of cavitation phenomenon, which involves evolution of ethylene that acts as a combustion promoter. The effect in question is supported by the results of tests carried out on a high-speed diesel engine.

Keywords: turbocharger, switchable turbochargers, fuel efficiency, partial loads.

The article describes layouts and historical development of MTU, «Mitsubishi», MAN and «Honeywell» supercharge systems featuring switchable turbochargers. The sources reviewed demonstrate the potential of supercharge parameters improvement due to the use of switchable turbochargers at partial loads, which results in higher overall fuel efficiency.

Keywords: reciprocating engine, turbocharger, gas, magnetic and combined gas/magnetic rotor bearings.

The authors overviewed a number of patented noncontact (low-friction) supports for engine turbocharger rotors, such as gas, magnetic and combined gas/magnetic rotor bearings. The test result are presented for various turbocharger designs featuring noncontact supports.

Keywords: thrust bearing, friction surface, laser texturing, measurements, friction coefficient.

Experiments have been carried out to evaluate the effects of friction surface laser texturing on friction coefficient and lubricant layer thickness in hydrodynamic thrust bearing. The test results were compared to those on bearings with conventionally-treated surfaces. The authors came to the conclusion that there is an urgent need for the development of mathematical models, algorithms and simulation codes to identify hydromechanical characteristics of bearings with laser-treated surfaces.

Keywords: structural steel, design strength, elastic properties, gas-impulsive treatment.

Impact resistance of high-strength structural steel may be enhanced through the treatment with low-frequency gas stream, added with percussive action of hollow steel balls. The technology is shown as contributing into hardened steel better tempering and higher reliability of steel parts thus treated. Gas-impulsive treatment of steel wound springs results in increase in their relaxation resistance: compression spring — by 20 %, tension spring — by 50 %, torsion spring — by 2,6 times.

Keywords: reciprocating engine, no-dismantle repair, serpentine trybo-compounds, repair coating, service life extension.

The author analyses evolution and structure of antifriction coating of engine parts remanufactured with serpentine trybo-compounds (PBC-process). Higher water content in engine exhaust gas is mentioned as one of consequences involved in PBC-process.

Keywords: motorcar engines, water/oil cooler, lower crankcase, cooling/heating, oil temperature optimization.

An water/oil cooler located in engine lower crankcase is proposed as a means of oil temperature optimization. Cooler effectiveness and optimization of oil temperature in a lower crankcase are confirmed with laboratory and field tests, including cold start in winter season.

Keywords: diesel engines, NOx emission, smoke, fuel injection systems.

One paper in question considers integrated solutions for fuel injection systems targeted at the improvement of engine environmental performance. A physical simulation technology was developed to evaluate the effect of ultrahigh fuel injection pressure on emission performance, including optimization of number of holes and nozzle hole diameter for higher injection pressure. Another paper presents a new fuel injection system developed by «Yanmar CO., LTD.», Japan in cooperation with «Woodward GmbH», Germany. Their «electronically-controlled fuel injection device», however, differs from widely-known common rail systems. A new system features conventional type injector and high-pressure injection pump with electronically-controlled solenoid valve. Such a solution involves no high-pressure accumulator, which contributes into higher reliability and safety level.