该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 Oxides of nitrogen (NOx) emissions from marine diesel engine by fuel combustion source lead to serious environmental problems. A lot of researches on the NOx reduction technology development have been conducted. One of NOx reduction technologies, Selective Catalytic Reduction (SCR) is a technology proven in many industrial fields. IMO (International Maritime Organization) Tier 3 regulation is scheduled to take effect in emission control areas (ECAs) from Jan 1st 2016, in accordance with the mandatory requirement. In order to develop technology which is able to meet the regulation, Doosan Engine has developed SCR from 2010. DelNOx is Doosan Engine’s brand name applied to Low Pressure SCR system. DelNOx also is mounted at the exhaust gas funnel downstream of the after turbocharger. The DelNOx catalyst is the low temperature catalyst enhancing NOx reduction efficiency at lower and wide temperatures range over 220°C and improving resistance to sulfur. The reactor is provided with an automatically operating soot blowing system. By using soot blowing on the surface of the catalyst, dust deposits can be prevented and the catalyst life-time can be increased. The hybrid dosing system is composed of four main units such as blower, oil burner, urea supply unit and decomposition unit. The components in the hybrid dosing system are mounted on a skid frame and are easy to install and maintain. Functions of hybrid dosing system are urea decomposition, catalyst regeneration and pre-heating before SCR operation. NWACS, control system of DelNOx is an effective system to interface with engine and operate easily. DelNOx has been verified by the Classification society, DNV-GL in 2013, according to Scheme-A. This statement of compliance concerns the first-ever Low Pressure SCR on a low speed diesel engine. Also, DelNOx has been verified by both MDT and Win-GD, 2-stroke diesel engine designers, in 2014. Doosan Engine received the first order of Tier 3 compliance 2-stroke diesel engine with SCR in the world from Samsung Heavy Industries, its ship owner is Reliance. DelNOx has been designed and manufactured by Doosan Engine’s technologies. DelNOx together with 2-stroke diesel engine will be tested and confirmed on test bed by 2015 and installed on 87k ethane carrier and delivered to ship-owner in 2016.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 The micro ignition dual fuel engine is one of the most effective means to achieve energy conservation and emissions reduction. It not only improves the engine emissions, but also retains the high efficiency. The mixture of natural gas and air is ignited by a bit of diesel near the end of the compression stroke. Therefore, the investigation of the diesel injection law has an important effect on the combustion and emission performance optimizing of micro ignition dual fuel engine. In this paper, a three-dimensional CAD software CATIA was used to simulate the geometric modeling of 2135G combustion chamber structure. Meshing and numerical calculations were accomplished in the software AVLFIRE. Using methane chemical kinetic mechanism as a combustion model, the chemical kinetic mechanism and CFD model coupling calculating was adopted. The coupling calculation results was compared with 2135G dual fuel engine experimental data, comparative results showed that they are in good agreement. It is proved that numerical model can effectively predict the influence of diesel injection law to the actual work process in a dual fuel engine. The influence of fuel injection law to micro ignition dual fuel engine combustion process was investigated in this paper. The influential factors are divided into diesel injection timing and quality of ignition diesel. The results showed that when the quality of ignite diesel is fixed, advanced the injection timing appropriately was conducive to atomization of diesel. This could provide more ignition energy and ignition source, and it was in favor of diesel igniting natural gas. These measures could lead to a fast and complete combustion, CO emission reduced, power performance improved, but nitrogen oxide emissions would be slightly increased. The research results in this paper can provide important theoretical guidance for micro ignition dual fuel engine and it can be used to optimize fuel injection parameters.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 The Bergen B-series 32cm bore engine was conceptuated back in 1983 and first went into commercial service in 1985. By 2010, the B-series had gone through several development stages, including introduction of gas variants for powergen as well as marine mechanical drive applications. Considering its, then, 25 years technical life span and future challenges in the different markets and applications, an innovation process was started for further upgrades and improvements. The innovation process spawned a concept leading to the first clean sheet engine platform from Bergen Engines in a decade. Increasing the power output per cylinder as well as the power flexibility whilst reducing fuel consumption, emissions and life-cycle costs were obvious targets. A significant amount of time was spent initially, but also throughout the project, to incorporate technical solutions based on feedback and recommendations from owners, operators, service technicians and mechanics. This includes enhanced equipment health monitoring and surveillance systems enabling not only condition-based maintenance and spare part sourcing, but also a minimization of failures and downtime by continuous data acquisition and evaluation. The main focus, however, was given to the engine architecture - the block, cylinder heads, liner and the connecting rod as the engine’s performance is heavily dependent on the successful integration of the power pack elements. In doing so, a sustainable power output of 600 kW per cylinder could be achieved for both in-line and V-, diesel and gas engines at 750 and 720rpm. Moreover, the active use of modern engineering tools and front loading methods allowed for global optimization of the whole engine structure providing improved material utilization in the block and crank shaft as well as add on modules and appendices. The block stiffness was significantly increased resulting in reduction of the vibration and noise levels. At the same time, the original footprint was practically maintained. Another important feature incorporated is the common basic structure shared between all fuel types so that a rebuild from diesel to natural gas or dual fuel can be carried out by switching power packs and adapting the fuel system. This paper focus on the key aspects of this development programme and process and presents an overview of technical and performance data of the first B33:45 in-line diesel engines.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 It is important to give the adequate boundaries at the turbine inlet when numerically modelling the one-dimensional simulation task (1D CFD) for unsteady flow in the exhaust system of a TC piston engines. The mostly wide used way is when the turbine characteristics are taken for the turbine reflected exhaust pulses calculation, and these characteristics are obtained on the test bench at stationary conditions. In such cases, the boundaries ratios for numerical calculation are taken only at the one centered section of the turbine inlet. This method may not provide a satisfactory results for the pulse systems calculation in case of the turbines of some particular geometry with or without blades snail nozzle outlet with an extended nozzle cut, which length is equal to the length of the median circle diameter at the entrance to impeller. Since the length of this circle may have a size comparable to the length of an exhaust manifold itself. In this case, it is necessary to consider the distribution of pulses interaction with the impeller over the median circumference diameter. Experience shows that instead of the complicated gradual distribution along the length of the interaction one can use the model when the input to impeller conventionally concentrated in two sections – at the entrance to the cut-off nozzle and at its outlet, with this the inlet to the nozzle cut-off is represented as a tree branch. The numerical calculation of unsteady flow before the first and second cross-sections performed as a continuation of the 1D modelling of exhaust manifold, but considering its constrictor geometry and its losses in the nozzle. The flow calculation in relatively short ports of impeller is performed in a quasi-stationary formulation with the usage of a shock of discontinuity methods. We developed the special method for accounting of the separated flow losses at the high values of the attack angle at the inlet to impeller. Verification of the developed calculation method for interacting pulses was carried out on a special experimental test bench consisting of solitary pulses generator, manifold and the turbine. Relevant calculations performed numerically with the usage of a shock of discontinuity methods (Godunova methods) showed a good agreement with experiments.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 GE Transportation has launched an updated EVO diesel engine to meet the requirements of EPA Tier 4. The base engine with the largest production volumes continues to be the locomotive version of the 12 cylinder EVO rated at 3375 kW. Additionally, the L/V250 engine series has been developed to serve the marine market in variants from 6 to 16 cylinders. The EVO engine has been one of GE Transportation’s most successful products. Over 7500 engines have been built to date. The product line has been expanded from its original offering to serve higher power applications and the marine market via the L/V250 engine series. The new engines use cooled exhaust gas recirculation (EGR), 2-stage turbocharging, Miller valve timing, and highpressure common-rail fuel injection, along with sophisticated control strategies to achieve an "in-cylinder" solution. This approach meets the exhaust emission requirements while maintaining excellent fuel efficiency and provides a compact package with cost, installation and space advantages, since no exhaust after-treatment system is necessary. However, the "in-cylinder" approach imposes significant challenges for the engine designer. This paper will describe the combustion system configuration, performance parameters, along with some of the more challenging aspects of the mechanical design/development and field test experience.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 During the recent years, considerable efforts have been made to improve the fuel efficiency of ocean-going ships. The main focus of the design improvements has been an efficient hull form and main engine choice and tuning. Furthermore, the new global and local rules for energy efficiency or emission limits in shipping are creating opportunities for introducing new alternatives to the machinery and fuel choice in even the simplest cargo ships. In current ships, with diesel engines as main source of power, approximately half of the fuel energy is utilized as propulsion power or electricity to ship processes. The other half is lost and delivered to sea as waste heat. The four main sources of waste heat in a marine internal combustion engine are the flue gases, scavenge air, jacket water and lubrication oil cooling. These waste heat streams can be divided into different temperature categories. Furthermore, depending on the temperature level a portion of this waste heat could be utilized as electricity or heating energy purposes in ships. In this article, several interesting technologies for enhancing ship energy efficiency were reviewed. The selected energy saving technologies included natural circulated boilers, thermal storage, Organic Rankine cycle, compression heat pump, absorption chilling process, efficient ship auxiliary cooling circuit and onboard direct current distribution. The waste heat recovery technologies require individual power inputs and they also absorb and reject heat at individual temperatures. The target of the study was to apply these technologies to simple cargo ships that represent the most common type of ship machinery set up. The technologies should be integrated in such a way that total fuel consumption of the vessel is minimized. The ship-specific fuel saving potential depends always on the actual operation profile that can be to some extend always evaluated at the early phases of ship design project. A multi-domain ship energy flow model in Simscape simulation environment was utilized for the study. The ship model included all main components in the ship machinery, including the most relevant auxiliaries. The model and its components included the necessary functionalities and the system requirements and limits that are relevant for concept level design. Once the system components were defined, the expected yearly operation profile was included in the model, including estimation of the electricity consumption, propulsion power consumption and heating- and cooling requirements. After this, the true saving potential in the system was evaluated by modelling the ship fuel consumption. Also, exergy analysis was performed for the ship main components. Based on the analysis, the characteristics of improved, energy efficient machinery for a cargo ship could be recognized. As a result of the study, various types of waste heat recovery technologies available onboard ships were studied from the perspective of technical principle and application feasibility. Furthermore, an optimal solution for improved, energy efficient cargo ship machinery was defined, considering the pre-defined system limits. With the studied technologies the excess engine heat could be utilized to meet the cooling, heating and power demand onboard that otherwise would require additional fuel. The developed solution included a new system analysis method for supporting the ship concept development. The whole method aims for holistic optimization of ship energy efficiency.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 Under the guidance of the International Maritime Organization (IMO) the emission levels for marine applications are regulated by MARPOL Annex VI. NOx, SOx and EEDI limits are in a steady process of tightening during time. The next stage of NOx emission reduction, the IMO Tier III emission limits, will be implemented from the 1st of January 2016 and will enforce significantly more stringent NOx emission targets for ECA areas. Apart from the lowered emission limits, the major driver for the engine development of marine applications is to maintain and possibly increase the engine efficiency. To reach both the emission and efficiency targets, the complexity of engine concepts has and will continue to increase. Depending on the engine size, application and region of operation, several solutions, including internal and external engine measures, are under investigation to comply with current and upcoming legislative regulations. While material and development costs for new technologies play a decisive role for manufacturers, for end users the consumables are an important cost factor. Conventionally, these are determined by the fuel costs and thus by engine efficiency. Meanwhile, however, the costs for emission reduction in terms of operating fluids take on an important role. In this study, operating cost optimized and reliable engine system concepts from the perspective of the end user shall be determined. This study is based on a medium speed Diesel engine application, operated completely in the ECA. The technical implications, financial aspects and advantages or disadvantages of the individual emission control concepts and technology packages are discussed. These include both engine internal and after treatment measures. The bore/stroke ratio and the piston speed are figures, which have to be defined carefully in the layout phase of the engine. Peak cylinder pressure, BMEP and displacement for a required power output are also important figures which have to be optimized. For the thermodynamic side the combustion process (fuel system), the gas exchange phase (air system) and the mechanical losses (friction) have to be considered. This investigation will start with state of the art engines as base line and will check several CO2 reduction regimes. The optimal combination of technologies from a point of view of investment cost, total cost of ownership, as well as operating costs is discussed. This presentation will give guidelines for OEM’s and customers as well to understand critical issues in the definition phase for future projects.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 Technical demands for journal bearings in combustion engines are highly varied, and often in contradiction to each other. Requirements are resistance to wear, fatigue, corrosion, cavitation; sufficient emergency run and smooth running-in behaviour. Further challenges may arise from manufacturing and operational environment. Adaptability to manufacturing tolerances as well as insensitivity to original dirt and foreign particles is required in applications as well as robustness to operation and the possibility to perform bearing changes directly in the field. Driven by IMO Tier III regulations ongoing trend towards higher fuel efficiency and increased power density in diesel, gas, and dual-fuel engines, accompanied by increasing peak oil film pressures and simultaneously a reduction of minimum oil film thickness, put ever increasing demand on materials used for bearings, approaching the performance limits of conventional products. The strengths of state-of-the-art bearings are divided – while journal bearings with standard sputtered overlays provide the highest load carrying ability they are vulnerable to dirt, whereas conventional electroplated bearings offer high tolerance to foreign particles at the cost of reduced life time and wear resistance. This paper will present the recent development of journal bearings for high and medium-speed diesel, gas and dualfuel engines combining the robustness and dirt tolerance of conventional electroplated three-layer bearings with the wear resistance, and longevity of standard sputter bearings. This is achieved by a leaded or lead free bronze lining with a tin-based sputtered overlay consisting of a conforming, ductile matrix as the main component, containing a loadcarrying structure of hard particles to provide the necessary mechanical strength required for loaded bearing shells. An overview of rig testing results for wear resistance at medium and high speeds as well as for dirt shock tolerance will be given in comparison to standard bearings, complemented by results from engine tests of prototype bearings. Additional development aspects for adaptive journal bearings will be discussed, addressing measures to further prolong the service life and field performance of journal bearings. Such are advancements of the development of electroplated overlays for bearing diameters up to 450 mm, combining high strength tin based materials with extremely soft micro-alloyed running in layer. Such materials proved to show excellent ductility while massively increasing fatigue strength. We will further present material design of tin-based overlays that allows for gradual hardening of initially soft and conforming overlays during engine operation. Such an approach can provide the required adaptability during the run-in and will subsequently gain mechanical strength further extending service life.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 Emerging from a decade’s long experience in propulsion and power generation by diesel-engines and gas turbines MTU Friedrichshafen is developing innovative E-drive systems. Besides internal combustion diesel-engines those systems comprise electrical machines for both, propulsion and on-board power supply, the according power electronics, switchboards, and optionally energy storage devices. All these components are controlled and monitored by a supervisory control and data acquisition system providing the total bridge and engine room equipment required for operating the vessel. Emphasis is laid on the total integration of all components and systems by MTU’s MELT approach, i.e. the implementation of Mechanical, Electrical, Logical, and Thermal features. The E-drive system is based on a modular concepts, which can be adapted to the specified vessel sizes and types, applications, modes of operation, etc. This paper deals with the concepts of different approaches for a production yacht and a mega yacht. While the production yacht was realised as a technology platform and demonstrator, the mega yacht features a highly innovative system based on state-controlled variable speed electric power generation combined with direct diesel engine propulsion and controlled by a patented Supervisory Systems Controller. This controller enables the adaptation of the operation of the diesel-engines for electric power generation according to their actual condition as well as the desired optimisation criteria, such as minimum fuel consumption, maximum performance, maximum redundancy, etc. Both vessels provide complementary experience to be presented.

该论文已在赫尔辛基举行的第28届CIMAC世界大会上发表，论文的版权归CIMAC所有。 In this work novel various internal purification methods were numerically analyzed on a large-bore medium speed diesel engine, under different valve close timings, geometric compression ratios, injection timings and EGR rates, to evaluate their potentialities of emissions abatement. In addition, two types of novel combustion chambers, defined as Chamber One and Chamber Two, were designed and experimentally tested for NOx reduction abilities. Numerical results show that, as the intake valve close timing is advanced up to 50°CA before BDC, NOx is reduced by as much as 27%, while the peak of premixed combustion heat release rate is increased, which can weaken Miller cycle’s ability to reduce NOx emissions. Moreover, the peak of premixed combustion heat release rate can be reduced by increasing the geometric compression ratio up to 15.4, and combining with a 6°CA delay of injection timing, NOx emissions can be reduced by 55.3% from the baseline. Furthermore, over 80% NOx and 20% soot reduction can be achieved, when the above schemes are cooperated with 15% EGR with a constant air fuel rate by raising boost pressure, which can avoid NOx increase from low oxygen concentration. Thus, the trade-off relationship between NOx and soot can be compromised. Afterwards, two novel combustion chambers were tested separately under E3 cycle to evaluate their emissions reduction abilities. Chamber One allows mixture to spread wider resulting in 6%-14% NOx and 5.7% fuel consumption reduction at medium and high load. Chamber two improves combustion process by providing injection spray with open space in the direction of spray development and reducing wall-wetting, and reduces 1.8-2.5% fuel consumption with an original level of NOx emissions at medium and high load. In conclusion, NOx and soot can be reduced simultaneously by using moderate Miller cycles combining with moderate EGR, and novel combustion chambers show great potential in NOx abatement.