论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。Development and application of ad-nition. Pulsed laser illumination was used for visualiza-vanced engineering tools-for description, prediction of fuel jets, from which information on fuel jet pen-and optimization of the 2-stroke Diesel engine process penetration, jet velocity, and spray angles could be gathered essential for development of the marine engines. For this purpose a high-power laser and a custom of the future. Here, recent developments of optical tom designed imaging system was mounted directly and laser based imaging tools will be presented. Such onto the optical cover. The fuel jet data is qualitatively tools can lead to both increased understanding and compared to results from KIVA simulations, in order to predictive capabilities of for example the scavenging tune spray parameters in the numerical model. The process, fuel spray structure, flame ignition, and ther-same laser system was also used for measurements mal loads. For optical studies access to the combus-of in-cylinder flow velocities, in order to characterize tion chamber has been achieved using sapphire win-swirl and scavenging. Particle image velocimetry(PIV)was used for those velocity measurements. Finally, in-frared imaging was employed for two purposes, firstly for capturing the evolution of piston temperature distributions during single engine cycles and secondly for visualization of scavenging of hot product gases.

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。For diesel engines, which are commonly used as the main engines of domestic vessels the electronic control technology is recently considred as effective to environmental issues. In order to meet environmental regulations and to satisty customer needs, Yanmar has developed the EUP(Electronic controlled Unit Pump) system for medium speed four-stroke diesel engines. EUP system consists of jerk type fuel injection pump, solenoid valve, ECU and sensors. In this system, fuel injection pressure is depending on cam speed. However, solenoid valve can control fuel injection timing and fuel injection quantity depending on engine operating condition. Then, this system can improve fuel consumption, NOx emission improvement of trade-off relation), smoke generation and ship handling As to improving fuel consumption combustion was improved and fuel injection timing map was optimized. Smoke generated at the engine start and acceleration has been reduced to less than 50% in comparison with conventional engine by con trolling injection timing and fuel limiter. ECU has the function to improve ship handling like clutch engaging and crash astern maneuver. At a moment of engaging the clutch, high load is put on the engine and engine peed goes down. Increasing engine speed just be fore engaging the clutch and controlling fuel injection quantity reduce the drop of engine speed. As result of this, ship handling during docking and undocking is improved. For the marine propulsion engine, high reliability is required especially for the ship with one shaft and one engine. In this case EUP system has 2 ECU and 2 important sensors. When main ECU or important sensors fail, system is switched immediately from the main to the backup. Basic structure of fuel injection pump is same as conventional mechanical engine and conventional fuel injection nozzle is available to us therefore EUP system is easy to retrofit. First delivery of this system to the market was in October 2009 as a propulsion engine. As of November 2012, this engine has been operated more than 4,000 hours. As the next step, Yanmar is developing EUP for the marine auxiliary engines which heavy fuel is used for. Auxiliary en-ne is main product of Yanmar and it is used in world wide marine transportation. In 2013, CO2 regulation by IMo will go into effect and EEDI (Energy Efficiency Design Index)is applied to indicate the energy efficiency of the ship, which is calculated in design stage From the point of view of the ship builder, the technol ogy like solar power, wind power, air lubrication sys-tem and re-designing the shape of the ship are considered. On the other hand, the engine manufacturers improve EEDI by developing gas engine, heat recovering system and improving fuel consumption. Of these fuel consumption is a biggest concern. Therefore, they make great effort to improve it. In latest test result of Yanmar, 2-3% of fuel consumption was reduced at the partial load of auxiliary engine. Yanmar believes EUP system is one of the solutions to improve EEDL

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。A novel' Self-tuning engine' control con-combustion efficiency, emission levels and overall sta-cept has been developed by Wartsila which ensures bility. To provide the best control performance for an optimal control of the engine throughout its lifetime, arbitrary process, it is essential that the control param- without the need for manual adjustment of the control eters are closely matched with the dynamics of the parameters. For large low-and medium-speed inter-process. For large low-and medium-speed engines, nal combustion engines, the process dynamics is sub-the dynamics are affected by several factors, such as ject to significant variances due to nonlinearities and the operating point of the engine, external conditions a wide range of operating conditions. To ensure the and mechanical wear of components. It follows that control quality at all times, the behaviour of the closed-to guarantee a good control performance throughout loop controllers need consequently to be continuously the lifetime of the engine, it is necessary to adjust matched with respect to the state of the process, sub-the behaviour of the regulators in accordance with the ject to control. Failure to do so typically results in in-dynamic changes. Typically, gain scheduling control creased fuel consumption and emissions, and exci-schemes are used to cope with the dynamic influence tation of oscillations in dynamically linked processes, from the operating points. This approach, however, which otherwise would be stable. For example, if needs periodic manual re-tuning in order to meet the the wastegate valve is slowly oscillating due to poor long-term expectations. To deal with these variances, control parameters, it will directly affect the efficiency Wartsila has developed a self-tuning control concept, of the fuel combustions and the fuel-injection control. which automatically adjusts the behaviour of closed-With the increased price of fuel oil and stricter emis-loop controllers of the engine so that optimal control sion legislations,a large number of various advanced performance is achieved at all times. Diagnostic fea-technologies have been developed, such as electron-tures have been, in addition, included in order to de-icaly controlled fuel injection, high pressure fuel sys-tect faults within the closed-loop circuit in order to detems,2-stage turbo-charging, exhaust-gas treatment tect malfunctions despite the adaptivity of the control systems, variable valve timings, etc. That is, modern loop. In this paper, the self-tuning engine control con-marine and power plant engines comprise of an in-cept is presented with examples from full-scale engine creasing number of complex sub-systems which are tests, proving the robustness and performance of the dynamically interlinked. The question of how well control strategy and the performance of the self-tuning these sub-systems are controlled will consequently engine.

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。4190 series diesel engine, which is a type of 4-stroke medium-speed turbocharged marine diesel engine, is widely used in ocean-going ships.The simulation model of 4190ZLC 4-stroke diesel engine is established by using AVL_BOOST software, the propulsion characteristics and load characteris-tics of working conditions are calculated using thismodel, and the laboratory platform experiment is completed under rated operating conditions. The accuracy of the model is verified by comparing the simulation and experimental results. The matching operation rules between 4190ZLC-2 medium-speed marine diesel engine and existing turbocharger is discussed by BOOST model established, the matching characteristics are obtained. The results show that4190ZLC-2 diesel engine and compressor operating performance is very good to meet the matching requirements of the turbocharger. These results will decrease the dependence degree for a marine engineer, then make it possible to scientific manage modern automatic engine room and improve the reliability of marine trust power plant.

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。Large-bore marine diesel engines quipped as main propulsion on ocean voyaging large vessels like container ships and crude oil tankers are supposed to possess very high reliability. One of the main factors that affects to the reliability of the main engines is the stable sliding of piston rings and cylin-der liners. IHI Corporation and Diesel United have conducted jointly numerous basic experiments and tests on wear monitoring between piston rings and cylinder liners, and measurements of oil film thickness between piston rings and cylinder liners of main en gines on vessels in commercial operation. The re-normal sliding mechanism between piston rings and cylinder liners that is hereafter referred as scuffing, and in developing effective cylinder lubrication meth ds that may be effective in preventing the scuffing These activities have lasted almost ten years. The findings obtained clarified the following phenomenon Namely, the scuffing is closely related to hard particles contained in the fuel oil (FCC), and to changes of en-gine operating conditions typically the engine speed Poor lubrication of piston rings and cylinder liners to be caused by the above mentioned effect is clarified to duce the scuffing Research results obtained during the period have clarified that the development of cylinder lubrication systems is quite effective in avoiding the poor cylinder lubrication. Furthermore, it is also important to develop the piston ring coating that may prevent the rapid growth of the scuffing phenomenon even when the poor cylinder lubrication being initiated, and that make the piston rings strong enough as to be immune to the presence of FCC on the sliding surfaces. Meanwhile, ship owners prefer to have longer overhauling intervals matching with dry dock interval due to economic reasons. The scuffng resistance of piston rings and cylinder liners be come extremely lowered when the piston ring coating is worn out in recently developed advanced engines which have higher output. Therefore, the life of the piston ring coating is required to be longer than the dry-dock intervals. Chromium ceramic coating is used is the piston ring coating that has relatively high reliability However, further improvements with respect to the piston ring coating lifetime and scuffing resistance are required to be realized for satisfying the market demands. The present paper reports the new generation oating for piston rings which will be able to fills a demand of a market thus developed. The first step taken at the development is to clarify the sliding characteris cs and the sliding mechanism between conventional plasma sprayed Mo coatings and chromium ceramic coatings. Plasma sprayed Mo coatings have high scuffing resistance with inferior coating life. Chromium ceramic coating films possess longer coating life than the plasma sprayed Mo coatings with lower scuffing re sistance than the Mo coatings. Numerous basic stud-es and various measurement results obtained on operating ships in the present investigation have yielde a concept for new coatings that should have superior scuffing resistance as the Mo coatings possess, and longer coating life than that of chromium ceramic coat s possess as targets of the new coatings to be deloped. The developed coatings are subjected to lab- lent properties. Namely, the developed coatings possess the scuffing resistance of about 1.8 times than lat of conventional chromium ceramic coatings, and the coating life as longer as more than 4.3 times than that of the conventional chromium ceramic coatings Furthermore, the developed coatings are confirmed to possess the same order of attacking property against the cy linder liners. Test conducted on operating ships have confirmed the same order of the coating life and superior sliding property as obtained at the laboratory tests. Thus, the actual applicability of the de veloped coating for main engines of operating vessels

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。The objective of this paper is to show the results gained from a medium-speed research engine using multiple injection in order to improve the engine performance and especially reduce exhaust emissions. The study is in fact carried out with a single-cylinder large-bore diesel engine(EvE), which is used only for research purposes. Its main feature is that the gas exchange valve timing is completely adjustable with an electro-hydraulic system that uses the engine lubrication oil to open the gas exchange valves. Moreover, the engine does not have a turbocharger, but a separate air compressor supply system that permits to change freely the intake charge air conditions; after the engine, a throttle valve tunes the exhaust back pressure. Many EVE components have been recently upgraded and the engine can withstand high indicated power and peak pressure values. This study includes the comparison between single- and multi-injection timing and the intluence on the engine performance. The different injection strategy is also combined with different valve timing: the Miller technique is used in order to reduce NOx, whose regulation is becoming more and more stringent. The research is carried out at high engine load. The in-cylinder compression pressure and the injection quantity per stroke are the parameters that are unchanged in every tested point. The combustion process is analyzed and the different setups are compared to understand the influence of the chosen strategy. The results show that it is possible to achieve high NOx reduction but the injection strategy must be chosen carefully with the valve timing

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。 For future gas and dual-fuel engines CFD-simulation methods. The easiest way to validate mixture formation is one of the most important devel-mixture formation simulation results is an indirect vali-opment areas to fulfill upcoming emission legislations dation with engine measurements. The validation is a and to improve combustion efficiency. Therefore MAN comparison of the simulated mixture formation quality Diesel & Turbo SE is optimizing the mixture forma-at start of ignition with engine measurements consid-tion of gas and dual-fuel engines with support of ad-ering emissions, knocking behavior and gas consump-vanced CFD-optimization techniques and single cylin-tion. For bigger variations this validation shows sur-der engine measurements. Today's CFD-optimization prisingly good agreement. Still investigating flow of an intake port with gas admission pipe is an it-tails and a direct validation of the mixture formation is erative process starting with an educated first guess not possible. Up to now no optical investigations con-design which has to be evaluated with simulation re-sidering mixture formation in the intake port for large sults and engine measurements. This evaluation is engines are known. To close this gap MAN Diesel base of the first optimization loop. The experience of & Turbo SE in cooperation with the Institut fuer Kol-the CFD-engineer is the optimization tool in that pro-benmaschinen of the Karlsruhe Institute of Technology cess. In general 4 to 5 iterations are necessary to im-have done PIV and Mie-scattering measurements on prove the mixture formation and flow behavior in the a modified flow bench for gas and dual-fuel engines.With this state of the art method it takes The measurements aimed on flow behavior and mix-about two weeks to reach the design target for mix-ture formation for different gas admission pipes and ture formation. With advanced CFD-simulation and intake valve seat rings for varying the flow behavior in optimization tools it is possible to get the best possi-the combustion chamber. The optical measurements ble design under consideration of the available design helped to rise the quality of CFD-simulation methods parameters within days. Nevertheless, the quality of and to improve the mixture formation of gas and dual-the CFD-optimization is directly linked to the quality of fuel engines to fulfill future emission legislation limits.

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。 Diesel and gas engines are considerably excited to structural vibrations by enormous forces caused primarily of fuel combustion and moved crank drive masses. Customers and classification societies demand low vibration engines. At MAN Diesel& Turbo(MDT), the engine vibration is limited to an acceptable level by purposive measures regarding the engine design already during concept and detail design phase-long before the first engine test and measurements are possible. Front loading by virtual engineering plays an essential role in the development process of diesel and gas engines. By combining engineering tools for analysis, simulation and optimization, virtual engineering facilitates a multidisciplinary and result-oriented product development. It supports classical design approaches as well as traditional experimental testing and validation. Virtual engineering assists the development process from the very first design idea to the final validation of the product. MDT demonstrates successful front-loading by means of the exemplary resiliently mounted 20V 35/44G engine, its latest four-stroke medium speed gas engine for power plant applications. MD T designs a low vibration engine, even though facing new, challenging boundary conditions such as high mechanical efficiency, higher firing pressures, light-weight design. In addition to topology optimization of the crankcase and an investigation of different firing sequences, an essential element in vibration optimization is a highly advancedvibration analysis and simulation process delivering accurate, reliable and predictive results. The vibrations of entire engines are investigated by means of Finite Element simulations and appropriate shell models. Because of its comparably small size and their parametric properties an evaluation of a high number of design variants within an admissibly short time is feasible. The simplification of the complex solid geometries to a mid face design of a shell model inevitably implicates deviations. However an optimum quality of the simulation model is indispensible. There-fore an updating procedure on numerical basis is introduced, which is already performed by standard long before any engine part is available in hardware for an experimental modal analysis. Moreover the numerical method offers equivalent results, that a late and ex-pensive test of core assemblies is not required. Each derived model of a core part e.g. the crankcase, base frame and turbo charger attachment is updated with respect to its original structural properties. The updating is carried out once firstly by correlating modal results like eigenfrequencies and mode shapes of reference solid FE models and their corresponding shell models and finally by adjusting parameters such asmaterial properties, element thickness or mesh density. More detailed information about the model updating procedure will be given by the paper. Due to cer-tain tolerances of boundary conditions, such as damping, non-linearity and fabrication tolerances, local inaccuracies will always exist. Local systems can react not exactly as predicted. Nevertheless MDT is conscious of these remaining, local inaccuracies and taking them into account already during the concept and detail design phase. Local design alternatives are de-termined by help of the vibration simulation and hold available for testing. If necessary, the appropriate solution is chosen and verified by measurement. High costs and long testing periods for the product validation are avoided. Finally the comparison of simulation and measurement results received later from the test bed illustrates, that the simulation has an excellent quality and accuracy. Having established the presented simulation process, MDT possesses the proper methods and tools respectively know-how, in order to cope with the ambitious engine design demands.This ends up in a low vibration design of new medium speed engines taking car

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。 Simulation is an important approach for the design of internal combustion engines. Zonal cylinder models are able to depict the essential physical and chemical processes of internal combustion. In this contribution, such a zonal cylinder model for calculating the rate of heat release of a methane gas IC engine is developed and implemented with a graphical programming language. This model divides the combustion chamber into zones described by properties of state like pressure, temperature, mass, and volume.At the beginning of each iterative simulation step, the model distinguishes the zone of unburnt gas from the zone of burnt gas. The combustion solely takes place in a third region called reaction zone which separates the zone of burnt gas from the unburnt gas, while the combustion process is modelled with an intermediate third balance zone. The volume of this reaction zone is assumed to be proportional to the current flame surface area and the turbulent flame speed. Theturbulent flame speed is approximated from the lami-nar flame speed and with the help of a pressure-and temperature-dependent approach proposed by Muppala et al. Furthermore, the flame surface gets deformed by the piston movement. This geometry is described as an ellipsoid of revolution, taking into account, that some areas of this ellipsoid might hit the walls of the combustion chamber. Here local flame extinction appears.A model by Boust et al. is implemented to calculate the quenching distance between flame and wall surface. This quench model bases on the balance of the heat release rate and wall heat flux.The amount of quenched methane gas is derived from the quenched volume. The achievement is a simple model requiring little computing time of just few seconds. The simulated rate of heat release meets the demand of sufficient precision on the one hand and of fewest equations on the other hand. The model approach allows analyzing a major source of the unburnt methane pollutant from such gas engines.

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。The oil film pressure is one of the key parameters in journal bearings influencing the performance of the bearings.A fibre optic sensor was developed for online determination of oil film pressure in journal bearings. The sensor head is integrated in the sliding surface of the bearing providing the possibility to measure the actual oil film pressure under load without disturbing the actual tribological contact.The sensor consists of two optical fibres, one to illuminate the measurement membrane consisting of bearing material and the other to collect the reflected light. The intensity of the reflected light is detected and converted to pressure data by using the calibration data. Functionality of the sensor can be confirmed after the mounting and between the tests by measuring the spectrum of the light reflected back to the input fibre. This way the distance between membrane and sensor head can be accurately calculated. Four optical sensors were integrated in a hydrodynamic journal bearing of a Wartsila Vasa 4R32 LN E medium speed diesel engine with four cylinders, maximum power of 1640 kW and rotating speed on 750 rpm. Online engine tests were carried out with different loads to study the sensor operation in real operating conditions. Test drives were repeated after several hundred hours of the engine use. The results showed differences in bearing pressure depending on the position of the sensor and on the operating cycle of the cylinders. The pressure peaks of all four cylinder work cycles couldbe identified in the measured pressure curves and the pressure variations within the pressure curves fit well to the diesel engine's work cycle and mass forces.The optical sensor was capable to measure the oil film pressure in journal bearing with a good sensitivity and repeatability during the tests which could be obsurements and by studying the noise of the results.The distance measurements showed that the sensor heads were integrated with robust riveting joint, anymovements were not observed during the long test period.