论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 The IMO Tier ll NOx regulations will come into force in 2016. This means that NO, emissions from large two-stroke diesel engines must not exceed a cycle value of 3.4 g/kWh, and NOx emissions must not exceed 5.1 g/kWh on the individual load points of the load cycle. To comply with the Tier Ill requirements, MAN Diesel & Turbo(MDT) is involved in a targeted and continuous development of exhaust gas recirculation(EGR) for NOx reduction on low speed two-stroke diesel engines. The latest investigations on MAN Diesel and Turbo's research engine in Copenhagen regarding the next generation of EGR system, scrubber performance, high speed and high efficiency EGR blower and water treatment system will be covered. The following topics will be described: confirmation test of integrated EGR system design, sulphur and particle reduction ratios in the EGR scrubber, blower performance and water treatment system functionality and requirements. The first MAN B&W Tier ll EGR diesel engine has been successfully delivered for a 4,500 teu container vessel. The following topics regarding the first Tier IIl EGR two-stroke diesel engine will be covered: engine integrated design with multiple turbochargers, EGR auxiliary equipment, installation aspects and shop test performance results. The development process of the 6S80ME-C9.2 EGR engine has resulted in a finalised EGR engine design, and implementation on other engine sizes is in progress.

论文已在中国上海举行的2013年CIMAC大会上发表，论文的版权归CIMAC所有。The rising concern for particulate matter (PM) emissions from maritime transport together with the adverse health effects associated with PM emissions have lead to several studies reporting PM emissions from marine diesel engines (MDE) running on marine heavy fuel oils. One metric among other that is being presented is the particle size distribution(PSD). Measurement of PSDs is associated with challenges related to controlling formation of nucleation mode particles by the use of dilution systems. These challenges are even greater when measuring on MDEs running on HFO due to the high sulfur content normally found in HFO. Sulfur is associated with enhanced formation of nucleation mode particles and the high sulfur con-centration in HFO requires an adapted dilution system to enable control over the nucleation process. In this study the authors is investigating the effect of dilution parameters on the formation of nucleation mode particles as well as adopting the dilution system for measurement of only solid PSDs. Measurement of solid PSDs gives higher repeatability as solid particles are regarded not to be affected by the dilution setting. During our experiments large variations in PSDs were observed when the effect of dilution parameters was investigated. Both changes to the particle size and in the particle concentration were found. Adapting the dilution system for measurement of only solid particles was successful. The system was able to measure only solid particles with very good repeatability for almost the entire size range measured. Compared to measurements on low sulfur fuels higher dilution ratios and significantly higher dilution air temperatures are needed. In this study dilution air temperature of 400 ℃ was applied while results indicate that 300℃ would be sufficient with as long as the primary dilution ratio is above 5. The high effect of dilution parameters on the PSDs highlights a need for defining and stating the dilution parameters when presenting PSD results to enable comparison and interpretation of the results.

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 The SCS method was applied to synthesize a series of TiMO2-δ(Mn, V, Ce, Fe, Zr, La, Co, Cr, Cu) nanocomposites catalysts. The catalysts with the active component of Mn, V, Ce, and Fe have high activity. According to the principle of complementary advantages, we prepare the binary compound metal oxide catalysts Ti0.9M0.05N0.05O2-δby the doping method, and find that the Mn doped catalysts of Ti0.9Mn0.05V0.05O2-δand Ti0.9Mn0.05Fe0.05O2-δ are highly active at low temperatures (<150-).

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 The development in almost every industry is currently being steered by environment, cli-mate and energy related issues. This is especially true for the automotive industry, wherein the advances in the combustion engines, independent of their operational principle and application, are strongly affected by them. While on the one hand it is mandatory to comply with the laws governing emission and environmental concerns, the modifications brought about should also cater to the demands of the customer in terms of higher efficiency and reliability. The current work, carried out in cooperation with GE Jenbacher GmbH & Co OG, deals with large-volume stationary gas engines used for power generation. Here, an at-tempt has been made to assess the tribological system comprising of piston ring and cylinder liner, which bears the highest loss in a combustion engine in terms of energy. The aim here is to optimize mechanical, thermal and tribological load bearing capacity of the system. The study also focuses on reducing the probability of spontaneous failure of this system to affect in a greater reliability. This in turn would ensure continuous power generation and safeguard the costs and resources. While modern engine test benches are more than capable of testing the aforementioned system of interest here, they are time consuming and highly cost intensive. Also, post-test damage analysis in such bench tests does not offer much of an insight into the happenings that had occurred during the test. Therefore, a model scale, damage-equivalent test methodology, was designed here for a comprehensive as-assessment of the system in a quite economical and time efficient manner. The tests were carried out on a TE 77 test rig from Phoenix Tribology with an analogous' Ring-on-Liner' configuration. The specimens were cut out from real components. To verify conformity between the two specimens, a light-gap-method is applied. The component-based test configuration facilitates damage-equivalent investigation of the piston ring-cylinder liner system. Post-test characterization was also carried out to elucidate and substantiate the findings from the tribological tests. The results obtained for a generic tribosystem consisting of a low alloyed and tempered spheroidal cast iron piston ring with a chrome ceramic layer, and an untreated lamellar cast iron (EN-GJL-250) cylinder liner, were considered as a reference. Numerous base materials with varying surface treatments have been investigated through a series of experiments to find an optimized solution which would offer an increased tribological loading capacity, with improved efficiency and reliability. The corresponding results facilitated in identifying an optimized system w.r.t base material, thermal treatment, topography, and lubricant. Finally, the results would be validated on a test engine in order to verify whether the chosen system would be suitable for a real life engine.

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 In a marine diesel engine, where residual heavy fuels are used as fuel, ignition and combustion are two very important properties that will deter-mine how much of the thermal energy in the fuel is converted into useful work. Till recently, the only parameter used to determine the ignition quality of the fuel has been CCAl(Calculated Carbon Aromaticity Index). Since this was considered inadequate, and outdated, the search for an alternate method resulted in a Fuel Combustion Analyzer Instrument (FCA). The instrument gives out an Estimated Cetane Number (ECN) based on the main combustion delay (MCD), an ignition parameter obtained from the test that rep-resents the ignition and combustion properties of the fuel. Residual fuels with small quantities of lighter fractions have 2 clear phases namely ignition and combustion during the burning process in a diesel engine. After testing hundreds of samples using this instrument, certain anomalies were noted. These include very low ECN values in fuels from Santos, Brazil that did not experience any problems during actual running and fuels with higher ECN have causing machinery problems. This could be mainly because of the cur-rent ECN calculation which is totally influenced by the ignition properties and somewhat oblivious to the combustion properties of the fuel. A new computation for ECN is suggested by Viswa Lab which includes additional parameter such as MCR, and also additional data from the FCA instrument. This New Estimated Cetane Number (NECN) is currently being validated with additional data points and information from ships on the performance of the fuel in the actual marine diesel engine.

论文已在上海举行的2013年CIMAC大会上发表，论文的版权归CIMAC所有。In the future, emission regulations for large gas engines will be more stringent. According to IED the EU has set a NOx limit of 200 mg/mn3 for large stationary gas engines. In certain countries and regions, limits under 100 mg/mn3 are even required. Without exhaust gas aftertreatment, these emission limits can hardly be met using conventional lean burn concepts. Possible additional strategies are the further enleanment through substantially improved igniti

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 New, stricter emission limits and engine development are continuously increasing the requirement to boost pressure level. Turbocharger manufacturers have been trying to fulfill this requirement by increasing the maximum pressure ratio of single-stage compressors, until material limits were achieved. The situation changed when engines with Miller timing were put into operation and showed their potential for additional emission reductions. As a consequence, a pressure ratio well above 6 was required. This was the impulse to start thinking about multistage com-pression with intercooling. From the start, the requirements of potential customers were included into the design. Based on application investigations, it was decided to keep the low pressure unit inside the standard product portfolio and develop a new high pressure turbocharger according to the special requirements. In reference to market potential, a medium size unit was chosen to be designed and tested as a pilot version. Highest efficiencies at low pressure ratios and increased mass flow capacities corresponding to high engine power density, together with higher mechanical load, were a considerable challenge in developing a new turbocharger. After the initial study, which de-fined operating conditions and ranges, the new com-pressor and turbine were designed using advanced CFD and FE tools. Some well-proven concepts from NR/S and TCR turbochargers were adopted for the project. The best versions were built by rapid prototyping methods and tested separately on compressor and turbine test benches. Simultaneously with production of prototypes, a new two-stage turbocharger test bench has been prepared capable of pressure levels up to 11 bar g, for which more sophisticated controls have been installed. The measuring system was up-graded for two-stage group measurements as well. The test of the main parameters confirmed the reliability of the design and thermodynamic expectations. Based on single stage and two-stage configuration measurements, a significant increase in the efficiency of the turbocharging system compared to just one stage was recorded. Special component tests were performed as well. In recent years, the TCX 14has been developed as the basis of a new series of high pressure turbochargers for two-stage turbocharging, suitable for the upcoming generation of reciprocating engines. The turbocharger performance fully covered the planned range and confirmed the potential of two-stage turbocharging to achieve charging group efficiencies far above max. single stage figures. PBSTurbo,a member of the MAN group, is ready to provide the new technology-comprising TCX as high pressure and TCR/TCA as low pressure turbochargers. In the paper the development steps are presented, with main focus on the TCX design features including comprehensive results of the component validation as well as test data in single stage and two-stage configuration.

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 The increase in fuel oil prices, tightening regulations regarding emissions no longer limited to NOx, the public discussion on global warming and requirements of the Energy Efficiency Design Index (EEDI) all clearly ask for an emission reduction. Ac-cording to the EEDI, CO2 emissions will have to be reduced by up to 30% depending on the ship type by 2025. This results in a vast range of applications for waste heat recovery systems in general and the power turbine of MAN Diesel & Turbo in specific. Using standard parts and proven technologies from our turbochargers for taylor made power turbine solutions, MAN Diesel& Turbo is capable of offering cost efficient and reliable solutions at present mainly focused on highly efficient 2-stroke engines. With the help of our power turbines, shipowners and power producers can lower their fuel oil consumption significantly. The application range of the power turbine comprises any mode where excess exhaust gas from the turbocharging system is available. This is especially the case when the 2-stroke engine is charged by highly efficient MAN turbochargers of the TCA series. Current projects show that the turbines are suitable for both stationary and marine applications. The modular arrangement of the power turbine allows for the utilization within full-scale waste heat recovery solutions such as the MARC_HRS system of MAN Diesel & Turbo, as mechanical drive for hydraulic pumps, as drive for power take in to the crankshaft or as standalone units for power generation in the form of turbo compound system with power turbine and generator(TCS-PTG).With the enhanced automation and control system, the stand-alone TCS-PTG on board the vessel is capable of operating in island mode which makes it an alternative to auxiliary gensets. With proven components from MAN TCA and TCR turbochargers, it is possible to provide power turbine solutions ranging from 500kW up to 4MW. The system consists of the turbine itself, with axial and radial type turbines capable of covering a wide flow range, gearbox, generator and an advanced safety and automation that can be adapted to the customers' specifications. Integrated gear solutions result in a compact and robust design. Matching the power turbine with engine requirements results in a superior overall performance of the complete system as regards the reduction of fuel oil consumption. The arrangement of the valves together with the drives as well as the advanced control system with redundant safety features are considered as MAN Diesel&Turbo's core competencies that guarantee a smooth and reliable operation. The convincing technical and commercial concept led to several customer orders. In the course of order processing, the performance of all components and systems has been scrutinized excessively via burner rig and factory acceptance tests. The results are used to further enhance the performance and reliability of the system. By consequently following the building block principle, we exploit internal and external synergies and make sure that our power turbine creates real value added, reasonable amortization periods and a sustainable reduction of the emissions of modern diesel engines. In the paper the design, automation and control philosophy is presented in detail as well as the product portfolio and the test results related to the current customer projects.

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 Heavy fuel oil is filtered by automatic back-flushing filters. The pressure rating of modern common rail systems is rising and the wear of abrasive impurities in the oil got an increased and no more acceptable influence on the components lifetime. Thus the engine manufacturers are developing more robust systems whilst the filtration should follow the higher requirements on filtration efficiency. The paper will summarise the experiences with new filter applications.

论文已在上海2013年CIMAC大会上发表，论文版权归CIMAC所有。 In order to improve the part load and transient performance of diesel engine, a three phase sequential turbocharging system with unequal size turbochargers was investigated by experiments in this paper. The performances of load acceptance processes under different speeds of three matching schemes (one small turbocharger, one big turbocharger and small with big turbochargers) were studied first. It is found that the response performance is better with small turbocharger, but the discrepancy of response time reduces as engine speed increased. The three phase switching boundaries of sequential turbocharging system under steady states were obtained according to the principle of optimal fuel efficiency. For speed characteristic, the small, big and small with big turbochargers are sequentially used along with the engine speed increasing from low to medium and high speed. For propeller characteristic, the two, big and two turbochargers are used along with the engine speed increasing from low to medium and high speed. Based on steady states switching strategies, the transient performance and soot emissions during acceleration processes were studied. It is found that the response performance and soot emissions of the sequential turbocharging system are better than those of one turbocharger system. But the switching process of cut in of big turbocharger and cut out of the small turbocharger has adverse effect on response performance, because it takes time for big turbocharger to speed up and for boost pressure to recovery. The switching strategies suitable for transient processes were also investigated. The allowable operation boundary of small turbocharger un-der steady states was used as small turbocharger switching boundary during transient processes, and two-phase switching strategies (shift between small and big turbocharger) was used instead. The results showed that the transient performance can be improved further by using transient switching strategies. For acceleration process with constant torque, the stagnation time of speed up during cut in and out point is reduced. For acceleration under propeller law, the stagnation phenomenon is more obvious with transient switching strategies, because at least one turbocharger is running when switching with steady state strategies.