Keywords: diesel locomotive, diesel-generator unit, diesel engine, locomotive load curve, fuel economy, dynamic characteristic, transient.

As far as locomotive applications are concerned, fuel economy and dynamic behavior are the most important propulsive engine performance characteristics. These strongly depend on locomotive load curve and typical speed/load map. The authors offered and tested a method of load curve optimization in terms of fuel consumption. Feasibility is shown of engine performance improvement by means of locomotive load curve optimization.

Keywords: locomotive engine type 8DM-21, import replacement, turbocharger type TCR14, optimization of air-gas channel geometry, diffuser, nozzle block, stand tests, development of combustion process.

In order to enhance a list of alternative turbocharger suppliers for locomotive engines, UDMZ examined possible adaptation of type TCR14 turbocharger from PBS Turbo (Czech Republic) to locomotive engine type 8DM-21EL2M. Optimization included tests of the engine featuring TCR14 turbocharger consequently equipped with several alternative versions of diffuser and nozzle block. Based on calculations and test results, optimum speed/load characteristic of engine equipped with modified turbocharger was achieved.

Keywords: reciprocating engine, two-stage supercharge system, Miller cycle, reduction in noxious emissions, controllable wastegate and air bypass systems, exhaust gas recirculation.

Review and analysis of modern trends in the development of two-stage supercharge systems (TSSS) has been carried out based on the last available publications of world-leading engine builders. Actually, very few companies today are able to afford research, design and manufacture TSSS. Such system with total pressure rate up to 12 and efficiency up to 80 % are essential to attain needed power efficiency while keeping emission performance to IMO Tier-III & EU Stage IIIB specifications without use of exhaust gas cleaning means.

Keywords: turbocharger, modelling, rotor system, plain bearings, vibration, fixed and rotating coordinate systems.

Considered are methods and applied aspects of rotor dynamics modelling for turbochargers featuring plain bearings. Included are the results of numerical analysis and optimization of a commercially available turbocharger rotor system that feature bearings capable of damping rotor vibrations at high rotational frequencies. Recommendations are offered concerning formulation and solution of rotor dynamics problems based on reduced description of rotor behavior in a fixed coordinate system. Rotating coordinate systems are shown as only advisable for modal analysis of rotor systems.

Keywords: gasoline, oxygen-containing additives, oxygenates, motor stand tests, noxious emissions, engine performance characteristics.

Presented are results of laboratory and motor stand tests of commercial gasolines with varying percentage of oxygen-containing additives. The article discusses influence of hydrocarbonic and oxygenic petrol components on techno-economic and environmental performance of direct-injection engine. Optimum oxygen contents in gasoline is defined from viewpoint of power, fuel economy and noxious emissions.

Keywords: metallic construction materials, corrosion resistance, thermal treatment, non-steady gas flow.

The article discusses treatment of metallic construction materials used for parts to be exposed to hostile environment with subsonic gas flow as a means to enhance their corrosion resistance. Specimens treated with HCl water solution demonstrate lower rate of mass loss compared with reference ones. Effect of corrosion resistance enhancement is shown to be a result of correction of material crystal structure defects under the action of mechanical waves. The longer is exposure of parts in question to hostile environment, the more pronounced is effect of gas-impulsive treatment on their corrosion resistance.

Keywords: boiler unit, automatic start system, solid fuel combustion, high-temperature fluidized bed.

Type KVP-1,74 VTKS boiler unit featuring high-temperature fluidized bed was modernized so as to secure efficient solid fuel combustion in automatic mode. Described are theoretical basis and tests of starting a boiler unit with automated ignition.

Keywords: Marine diesel engines, sulfur content in fuel, black carbon emissions, test methods, comparative analysis of results.

Stricter IMO specifications for noxious emissions are anticipated. Also, more exhaust compounds are likely to be regulated in near future for ships navigating in Arctic emission control areas (ECAs). This means that work should be launched to establish definition and methodology for black carbon (BC), which accounts for a considerable part of particulate matter (РМ) found in exhaust gas. The paper presented by the consortium of Finnish experts contains the results of BC measurements carried out on Wartsila 4R32 marine engine firing various fuels with sulfur content 0.1% to 3.5%. Comparative evaluation of the results allowed to define pros and cons of each of used measurement technologies, and assess their respective applicability to BC emissions from marine diesel engines.