An overview of Natural Gas Use in Ships: Necessity and Engine Supply

The article consists of analysis of existing and planned air pollution from ships control and prevention tools such Marpol 73/78 Annex VI, Energy Efficiency Design Index, Energy efficiency operational indicator, Ship energy efficiency management plan, Regulation on the Monitoring Reporting and Verification of shipping emissions, Carbon tax, Maritime emission trading scheme. Norms of these control and prevention tools are difficult to ensue using traditional marine fuels. Pollution rates getting tighter and alternatives have to be used, and some of them have long been known and are not widely used due to objective reasons. Such alternative is natural gas, and its use in ship power plants could reduce concentrations of nitrogen, sulphur, carbon compounds and other pollutants in engine exhaust gas up to acceptable level. The part of maritime sector choosing gas or dual-fuel engines due to tighter pollution rates, and the supply of these engines analyzed in last part of article

Research on the Energy Efficiency Indicators of Transport Diesel Engines under Transient Operation Conditions

In this study, we have investigated the efficiency of transport diesel engines CAT3512B-HD in transient braking and acceleration modes in 2M62M locomotives. A comparative analysis of the diesel engine performance has been performed at speeds of power increase and braking ranging from 4–5 kW/s to 17–18 kW/s. A decrease in the fuel economy occurred, and the main reason for it (compared with the steady-state operating condition at qcycl = idem) has been found to be the deterioration of the mechanical efficiency coefficient due to the loss of the additional equipment kinetic energy of the engine. The efficiency decreased by 3–3.5% under power increase operations and by 10–14% in the braking modes. The original methodology for the evaluation of the diesel engine parameters registered by the engine control units (ECU) in the engine operating conditions, mathematical modelling application AVL BOOST, and analytical summaries in artificial neural networks (ANNs) have been used. The errors in the obtained results have been 5–8% at a determination coefficient of 0.97–0.99

Mathematical Modelling of Diesel Engine Operational Performance Parameters in Transient Modes

This study presents innovative methods for solving practical challenges that occur during the operation of heavy diesel engines (DEs). The novelty of the method arises from the combined use of an artificial neural network, a single-zone DE combustion mathematical model, and data from real operation conditions. Using the proposed method, DE transient mode energy efficiency has been analysed, and the primary influencing factors have been identified: qcycl and dqcycl/dt. The adequacy of the method has been tested for CAT3512B-HD series engines installed on freight locomotives. The difference between the model results and experimental data has been 3–4%. CAT3512B-HD series DE transient operation studies have shown that at the low-load range of qcycl (up to 36% of nominal), the fuel consumption during transient operation increases by 10% compared to steady state operation. Transient operation efficiency is not influenced by the operation rate (dqcycl/dt) in the analysed -0.016 to 0.016 g/s range. Near the nominal power (qcycl increases up to 0.5 g/cycle), it is necessary to limit the dqcycl/dt range to 0.006 g/s to avoid overexploitation of the fuel by more than 100%. The proposed method has been recommended for practical use in optimizing vehicle operation load cycle structure by adapting the engine control to the concrete operation conditions, as well as for overall efficiency improvement

Research of energy efficiency and reduction of environmental pollution in freight rail transportation

The publication presents the results arising from the experimental and mathematical modelling studies, which mainly aimed to investigate the selection and optimization of the rational operation modes particular to diesel engines of freight locomotives in the possession of the JSC ‘Lithuanian Railways’ (AB ‘Lietuvos geležinkeliai’). The goal of the optimization is to increase the energy efficiency, reduce fuel consumption and emissions of harmful air pollutants to the environment from diesel engines of locomotives during freight transportation via the main lines of the Lithuanian railway network. A complex energy efficiency and environmental pollution assessment criterion KE–E adjusted for diesel engines of freight locomotives has been suggested. The use of KE–E on the basis of the conducted complex experimental mathematical computer modelling studies has determined that the reserves reducing fuel consumption, harmful emissions and greenhouse gas (CO2) emissions constitute 6÷15% on an average, and in the case of individual railway network lines they go up to 30%. The comparative emission of harmful components per fuel mass (NOx, CO, CH, PM) e´NOx, e´CO, e´CH, e´PM when carrying freight via the main lines of the railway network by trains weighing 3000÷7500 t has been singled out. The results constitute sufficient grounds to organise control of harmful emissions and provide an opportunity to solve practical tasks with a slight tolerance (3÷7%) taking account of diesel engines of locomotives used for transportation. It has been proposed to measure the freight transportation efficiency according to the complex criterion KE–E, indicates the energy efficiency and the assessment of environmental pollution originating from diesel engine of locomotives. The reserves for increasing the efficiency of energy usage have been studied according to the variational mathematical computer modelling data. A methodology for measuring the freight transportation rationality and estimating the optimal indicators has been proposed, using the values of the KE–E criterion for the railways freight transportation, as well as the technology for controlling the traction characteristics as well as energy and ecology indicators of diesel engines of locomotives in operational conditions. First published online: 20 Oct 201

VANDENS – DUJŲ ŠILUMOS MAINAI GAZ-LIFTO TIPO SKRUBERYJE

In order to reduce sulphur oxide emissions from ships the SOX emission regulations in emission control areas shall be strengthenedand allow only 0,1% of sulphur in marine fuels since 2015. High price of this type of fuel forces ship owners to search for alternativemeans of reducing SOx emissions. Most rational measure is to use scrubber technology. Main type of scrubber that has been widelyanalysed is “shower „ type scrubber. How ever even with widely performed research of these scrubbers they still have somedrawbacks that are of most concern for the owners of small ships. Solution – gaz-lift type scrubbers. In order to improve and adaptgaz-lift type scrubber technology for cleaning of exhaust gases a thorough research has to be performed. Important part of this researchis heat exchange between gas and water in gaz-lift type scrubber. This is done with CFD software – Flow3D. The Simulationresults showed that the temperature of exhaust gases passing the scrubber dropped to around 300-350 k. this results matches theexperimental data, confirms the adequacy of calculation and provides basis for the further use of these models in gaz-lift scrubberresearch.KEY WORDS: GAZ-LIFT, SCRUBBER, SOX, EXHAUST GAS CLEANIN

Research of characteristics of working cycle of high-speed diesel engine operating on biofuels RME–E and D–RME–E. Part 2. Indicators and characteristics of heat release in diesel cylinder

This paper presents material about using two-component RME–E and three-component D–RME–E biodiesels in high-speed diesel engines. The results of the analysis of fuel injection parameters described in Part I of this scientific paper – Research of characteristics of working cycle of high-speed diesel engine operating on biofuels RME–E and D–RME–E. Part 1. Indicators of fuel injection system and indicative process – allow conducting a coherent research of heat release in the cylinder of diesel engines transferred from operation on mineral diesel D to mixed biodiesels containing E. Effects of increased ethanol E in the biodiesel of 1A41 diesel engine have been analysed in a wide range of loads, ranging from 0.25 to 1.0 Penom. It was found that the result of the transfer from two-phase heat release to one-phase heat release is an increase in the fuel's economy of the engine for every 10% increase of E in the fuel (increase of indicative process efficiency makes up 0.4÷0.5%). Dependency of heat release and nitrogen oxide emissions in the exhaust gases remains the same for mineral diesel, RME–E and D–RME–E. Indicators of cyclic stability of the diesel engine, operating on biodiesels containing E ≤ 30%, did not exceed those that are common for diesel engines operating on mineral diesel

Comparative studies of the biodiesel fuel jet development dynamics in common rail and conventional design fuel systems

The results of comparative diesel and biodiesel (Rapeseed oil Methyl Ester (RME) and Rapeseed Oil (RO)) fuel jet structure studies by optical scanning method are presented. There is an interrelation between the dynamics of fuel jet development by the Common Rail (CR) with single-phase injection and Conventional Design System (CDS) and the parameters of mixture formation, which are typical for transferring the operation of the Diesel Engine (DE) from mineral diesel to RME and RO. The structure of the Diesel Fuel (DF) jet is significantly more heterogeneous by the size and number of droplets in CDS in comparison with CR. From the moment of the injection the presence of zones less saturated with fuel contributes to a relatively short induction period – 5° ca. compared to 11…12° ca. in the CR system. Using RME in the CR system in comparison with DF, increases the heterogeneity of the fuel jet, thereby causing a shorter (by 1…2° ca.) induction period in the whole investigated range of injection pressures of 60…160 MPa. The injection of a non-heated RO is accompanied by the shape and structure fluctuations of the fuel jet. RO heating to 65 °C stabilizes the structure of the jet and increases the share of less saturated zones. Promising way of use for the optical scanning method in the mathematical modelling of the DE working process is proposed

Geochemistry of the Dust Collected by Passive Samplers as a Tool for Search of Pollution Sources: The Case of Klaipėda Port, Lithuania

Geochemical investigations of total suspended particulates (TSP) help detect hotspots and emission sources in port cities with stevedoring operations. The aim was to reveal these sources via geochemical indices (gI). TSP were collected in Klaipėda using original passive samplers in ten sites during four periods, during one of them, in ten additional sites near iron ore stevedoring (IOS). The contents of 22 elements (PHEs, crustal, Br, Cl) were determined by EDXRF in TSP and characteristic dust (CD) of stevedored iron ore, apatite, phosphorite, potassium fertilizers, and in waste incineration ash. Median Fe content in TSP near IOS was ~29%. The significant anthropogenic origin of clusters Fe–Cr, Sr–P, V–Ni–Zn–Cu, Pb–As, and Mg–Ca, Br–S–Cl was confirmed by gI mapping and analysis of CD. Significant temporal variability of Cl, S, Sr, Ni, Br, V, and Zn due to weather changes was revealed. Near IOS, significantly higher values of gI were found for Fe and Cr, while far from IOS, for K, Sr, Ti, Rb, Cu, Al, Si, Zr, Ca, Mg. Significantly higher values of normalized enrichment factor near IOS were not only for Fe and Cr, but also for As, Pb, S, Mn, Br, and Cl

Diesel engine transient operational performance research to improve efficiency

The dissertation deals with the heavy diesel engines performance problems during transient operation. The main object of research is a diesel engine operating energy indicators and dynamic parameters of transient operating modes. These parameters significantly influence the energy efficiency of the engine in real operation conditions. Detailed analysis of these parameters allows to evaluate the cost-effectiveness of engine real operating conditions. However specialized research facilities and test bed experiments are needed to perform diesel engine transient operation studies. Therefore, methods are needed that allow to determine the dynamic parameters without special equipment, during real operating conditions. The main aim of the work – to carry out the heavy vehicle diesel engine operating conditions and operating parameters by experimental and mathematical modeling studies to establish and adapt methodology for diesel engine energy performance improvements in transient operation modes. The main tasks: to form a rational methodology for determination of diesel engines operating parameters and on that basis, develop and adapt technological measures to experimental data and transient operating modes. To investigate the heavy-duty diesel engines operating load cycle structure, determining the energy efficiency reserves and ways of improving the rational use of energy indicators. And develop and adapt mathematical modeling tools to the experimental data of diesel engine operating parameters