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。Thanks to the advantages of lower harmful emissions and noise, swirl-chamber indirect injection diesel engine has been widely used in small type non-road machinery. With the implementation of harmful emission regulations on non-road machinery diesel engines, swirl-chamber diesel engine regains attention from domestic and abroad internal combustion engine industry. In order to improve the fuel economy, the authors modified a swirl-chamber diesel engine, applying conical spray in swirl-chamber to improve fuel-air mixture formation and combustion processes. A 3-D CFD software package was employed to investigate the match of the conical spray and swirlchamber and analyze the performance of the modified engine. The simulation results indicate that with the application of the conical spray on the prototype engine, the fuel economy is improved due to finer atomization of conical spray in Swirl-chamber.

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。 Internal combustion development and value proposition within Wärtsilä is increasingly geared towards offering end customers solutions featuring flexibility, agility, and the highest efficiency in both on-shore and offshore applications for power plants and marine installations. The ’must haves’ for both the customers and also for Wärtsilä remain as being reliability, emissions compliance, and cost effective solutions. This paper will describe the main technology enablers for delivering these benefits, and will also give an overview of the products available and recently developed that incorporate them. The four-stroke product portfolio overview is divided into two papers: one reviewing diesel and the other reviewing gas technologies / products in more detail. It should be noted, however, that many technologies can naturally be applied for both. Primary measures, such as high pressure charge air systems, secondary measures such as exhaust gas after treatment, and multifuel operation, currently appear to be the most robust and promising technologies for compliance with existing and future legislation. They represent the boundary conditions to product development. Unplanned malfunctions are expensive. Therefore, in product development the target is to integrate simulation and self adapting systems. One of the key technologies for the future is 2-stage turbocharging. Wärtsilä presented this idea embryo for the first time at CIMAC 2004 in Kyoto. Through systematic work on this technology, the entire industry as well as customers have been able to harvest the benefits, namely fuel consumption savings, NO x emission reductions, and increased reliabil- ity. This paper will describe the products now available and those to come featuring the 2-stage turbo charging system. It will also describe the design, the measured customer benefits, and will highlight the issues observed from units that have operated for 10 000 running hours. The paper will also offer a description of the first commercial plants to operate with this technology in both marine and power plant installations. Another key technology is electronic fuel injection. Again here, Wärtsilä was a pioneer in the late 90’s when we introduced this as a means for cruise vessels to achieve low particulate and smoke emissions. The paper will describe the changes made from the cam driven pump-accu-injector system to the 2nd generation system. It will also show the improvements in reliability and customer maintenance. Finally, it will also show the improvements in fuel efficiency and flexibility compared to the 1st generation system, and the reasons behind these improvements, as exemplified in Wärtsilä’s portfolio of 2nd generation CR products.Variable valve mechanisms for optimum performance at all loads and increased flexibility under all conditions, has become the standard solution for most engines, the customer benefits being obvious. However, today’s 2013 systems are somewhat different than the in the late 90’s, when Wärtsilä first introduced them for large medium speed engines. Embedded automation is an enabler for most technologies being used on products in a reliable and repeatable way.Wärtsilä has continued the development of its UNIC system with increased functionalities, while maintaining high safety and offering a better user interface. The paper will describe the benefits of having one system.After treatment systems integrated on engines offer a means of reaching the increasingly challenging emission limits with high efficiency. The paper will include Wärtsilä’s experience and the customer benefits with such systems. The paper will finally include also an overview of the new diesel products in the Wärtsilä portfolio where the mentioned technologies are utilized. Examples include a new small bore engine / a locomotive adaption of the Wärtsilä 20 / the industrialized 2-stage turbocharged Wärtsilä 32 / field experience .

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。 Over capacities in the ship transport sector lead, after the crisis of 2008/09 in shipping, to a drop of charter rates income and especially in the container carriers business to super slow steaming, now updated to 10% maximum continuous rating (MCR).Flexible turbo charger cut out with it’s further fuel saving and operation improvements becomes more and more standard and can optimize the new operation range of big bore main engines. The coming new buildings are planned already for a service speed of 21 down to 14 kn with much smaller main engines in contradiction to the unsolved problems in high risk areas.Adaptation of cylinder lubrication to super slow steaming follow these needs. HFO sulphur content with a max. 3.5% S since 1.1.2012 and new universal cylinder oils take note of changes on the world fuel markets and emission control areas (ECA). On the other hand a few companies are developing wet- or dry-scrubber technologies to use soon, with high sulphur fuels, even higher than 4,5% S back again on board which will also be challenging for the engine environment of the future. The enlarged and changing different emission controlled areas (ECA and CARP) will need more attention to be paid in the coming future regarding safe engine operation and sensitive equipment especially with change-over in between different type of fuels. On the other hand the more complexity in technique and paperwork like, TIER I retrofit and more competition on the well educated human resources lead to faster educated crews with less practical experience being under high psychological pressure. A permanent drop of component quality and cost-down-design pressure in the market interfere with the higher demanding technique and less experience of crew which may lead to a higher potential risk or give a wide range of challenges for the ship operators to deal with. Additionally, coming systems and administration work like: ballast water treatment systems and regulation, piracy prevention, EEDI and SEEMP will give more challenges in very near future for the shipping industry. Furthermore, the coming LNG conversion for Baltic Sea operation before 2015, TIER III legislation, will lead to drastic increases of complexity in engine plants. and installa- tion of SCR catalysts, exhaust gas recirculation, water emulsion use and double stage turbo charging will raise the installation and operation cost and may overwhelm the limited resources of engineers.

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。Controlling structural vibration of marine engines continues to be a challenge as specific power increases and versatility is a demand. Modern diesel and gas engines should be capable of running both as propulsion engines with variable speed and generator set engines with fixed speed. For both applications,load response is of paramount importance. The same engine platform is normally used for applications using diesel-, gas-, propulsion- and genset-engines in several cylindernumbers. Finding a design solution for the rotating shaft system and the structural block system which works well for all combinations is a task which need consideration of many influencing factors. As vibration level is influencing engine reliability and life, it is important to chose a design solution with low vibration levels. However for obvious production and service reasons, the number of shaft and block variants should be kept to a minimum, often requiring that the same solution should be capable of sustaining all engine applications. The paper discusses how modern Multi Body Simulation tools may be used to evaluate different solutions for both shaft system and structural system, and take into consideration the influence of the participating systems. In particular it is discussed how various firing orders will give different possibilities for torsional tuning of the shaft system. For marine variable speed applications it is important that the engine can be tuned to run comfortably over the whole speed range both with regard to shaft torsional vibrations and engine structural vibrations. It is shown that different firing orders cause large influences to the X and H-moment of the engine block structure. Measures to avoid resonance at critical eigenfrequencies are also discussed.

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 pioneering Bergen SI lean burn marine gas engine portfolio has been established and launched to the market through the previous 8 years.The marine gas engine portfolio builds on the strong pedigree of the Rolls-Royce Bergen lean burn SI gas engines for land based power applications. The first steps towards the marine gas engine applications were taken by the initial adaptation of the classic KV-Gas series for gas electric propulsion in a series of Norwegian car passenger ferries in 2006. The first 16 engines have now accumulated more than 500,000 running hours with individual engines at 41,000 hours+. The next move was the introduction of the B35:40V marine gas series in 2008, and the newly designed C26:33 L-series in 2010. Both of which have been put to use in mechanical drive variable speed applications. In 2012 the range was completed by the introduction of the B35:40-L-series. The development of the marine gas engines aims at mechanical drive propulsion application as well as marine genset applications, both incorporating the ’Inherently Safe Gas Concept’ with double walled gas supply systems with ’block and bleed systems’ installed. Strong aspects of the marine lean burn gas engines are low specific fuel consumption, good transient load performance combined with very low NO x , SO x , CO 2 and UHC emissions. This paper will concentrate on: a) The development of the B35:40-series with emphasis on the L-version. b) Reviewing experience and practical aspects of lean burn gas engines in general and marine mechanical drive variable speed applications in particular. a) Engine Design The B35:40L Marine Gas Series is a relatively compact design comprising a 350 mm bore on a 520 mm cylinder distance. The stroke remains at 400 mm as for the V-version. Also, the engine series is equipped with the latest version of the fuel gas piping system where the engine is fed with a single pressure regulated gas supply which is split on the engine between pre-chamber and main chamber supply. This design allows a simplified piping arrangements on the engine and between the gas regulating ramp and engine without any sacrifices in performance. b) Practical aspects of using SI lean burn marine gas engines Applications so far employed and to be covered in this paper are: ferries for passenger and cars, cargo ships, RoPax ferries and tug boats with both gas-electric and mechanical drive of controllable pitch propeller, variable speed and variable load, also twin input- single output gearbox applications, including individual requirements for different applications.Included is also a review of the engine operation limits, as employed in the Bergen lean burn marine applications, showing how transient loading limits and load increase rates affect the applications of Bergen lean burn gas engines.

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。 Rising fuel prices and more stringent requirements in the field of exhaust emissions, such as nitrogen oxides, particulate matter and carbon dioxide are significantly increasing the pressure on the manufacturers of internal combustion engines of all categories to find, evaluate and apply technologies that contribute to a reduction in these emissions. As a result, interest in cylinder inner diameter surface coatings has risen considerably in the last three to four years, and particularly in the SUMEBore® coating solution from Sulzer Metco. Such coatings are applied by a powder-based atmospheric plasma spray (APS) process. The APS coating process is extremely flexible and can also process materials to which wire-based coating processes do not have access. Particular advantages become obvious when coatings are necessary made from high chromium containing steels,metal matrix composites (MMCs) or pure ceramics.The compositions of the coatings can be tailored to the specific challenges in an engine, e.g. preventing excessive abrasive wear, scuffing issues or corrosion attack caused by bad quality fuels and/or high exhaust gas recirculation rates (EGR). Cylinder liner surfaces from trucks, diesel locomotives and marine propulsion,gas engines for power generation and gas compression have been coated with such materials over the past four to five years in small and large series production. These engines have been tested successfully.Most of the tested engines achieved significant reductions of lubrication oil consumption (LOC), one of them in excess of 75%, reduced fuel consumption, very low wear rates and corrosion resistance on the liner surfaces, when compared to the currently uncoated cylinder surface (baseline). The paper will introduce the APS coating technology for ID cylinder surfaces and as an example will highlight the coating of cylinder surfaces in a 4,000 hp EMD 16-710G3 locomotive 2-stroke diesel engine. Details of the application of a corrosion resistant MMC coating will be shown, together with results obtained with the Da Vinci DALOC measurement technique in an engine test where the lubricant oil consumption was accurately quantified at 4 steady-state operating conditions typical of North American freight locomotive and which clearly showed the significant contribution of the liner ID coating to reduction of lubricant oil consumption (LOC). In addition the paper will give an example of an industrialized, fully automated SUMEBore coating equipment installed at a European truck OEM, for the APS cylinder surface coating of up to 250000 cylinder liners for a truck engine.

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。 Increasingly stringent exhaust emission legislation combined with economic pressure to realise the best achievable fuel efficiency, which recently also is expressed as CO 2 emission, make natural gas a promising alternative fuel for power generation plants and marine propulsion. This is due to the combined effect of high knock resistance of lean natural gas fuel/air mixtures, which enables high efficiency combustion systems and the lower carbon content in the molecules of natural gas which reduces CO 2 emission relative to liquid fuels. Setting the target for a new or updated product was driven by market requirements and availability of new technologies. The targets had to be validated by high level considerations in order to generate a robust project plan and achieve the best possible matching between objectives, resources and timing. As a result a preliminary selection of individual solutions is generated, which is expected to enable the realisation of the specification. In order to assess the consequences of each and every decision made right through to the final product a perfect balance between concise formulation and flexibility had to be found. This paper will present the methodology and highlights (based on simulation, test results and new components design) towards a complex engine power and efficiency upgrade development project based on an already existing engine platform.

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 paper will go into particular description about a number of methods for spherical surface processing of the connecting rod .Finally, we achieved the mass production ,and selected THK6111 CNC horizontal boring machine and special fixture, wrote the fanuc macro program, used the NC pallet (B axis), X and Z axes of the simultaneous three-axis control. Ultimately, we completed the rough machining and finish machining of the connecting rod spherical surface.Meanwhile, the new machining method improved the processing quality and efficiency.

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。 EPA Tier4, IMO Tie3 and EU3b emission limits require injection systems which enable full application flexibility and excellent mixture preparation. This applies to high speed as well as medium speed engines. NOx emission limits can either be reached by high EGR rates in the combustion chamber or by SCR after treatment of the exhaust gases.EGR applications require excellent mixture preparation and distribution to prevent soot formation during the combustion. Applications with SCR after treatment have a penalty due to additional reduction agent costs during engine operation. They have to compensate the reduction agent costs by significant improvement of fuel economy. This can be achieved by full flexibility of injection timing, the capability of multiple injections and excellent mixture preparation. Both approaches lead to the need of common rail injection systems with optimized mixture preparation. The papers presents system and component designs of the Modular Common Rail System for high and medium speed Diesel and medium speed HFO engines up to 2200 bar fuel pressure. These injection systems cover the full range from 100 to 350 kW/Cyl and have full system lay out flexibility for engines from L4 to V20 engines. The production roll out for the Diesel injection systems starts in 2013 for high speed and will be completed for medium speed engines in 2015. It is covering marine, Construction & Industry (C&I), locomotive and gen set applications. Measures to improve the performance, durability and robustness of the injection system down to component level are presented, focusing on the key components high pressure pump and injector. Optimizations of the high pressure injection components for fatigue stress, wear, cavitation and fuel atomization as well as the contribution of simulation tools are shown.

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 ME-GI concept is based on a diesel-type combustion process of a gas jet that is injected into the combustion chamber with high pressure between 150 and 315 bar depending on engine load. The ignition of the gas is ensured by injection of a small amount of diesel oil prior to gas injection the so-called pilot injection. This paper describes the ME-GI concept and its implementation on a dedicated test engine as well as on a production type engine. Furthermore, it also presents performance and emission results from a subsequent optimisation effort. Successful development of the ME-GI concept required a suitable research facility platform for thorough investigations and engine tests. Therefore, it was decided to retrofit an electronically controlled two-stroke low speed marine diesel research engine, 4T50ME-X, to gas operation. Retrofitting the research engine to gas operation required development and installation of gas engine components as well as development of a new control and safety system, which is added to the standard electronic control system. Before adopting all new components and software to the research engine, preliminary tests were carried out on a one cylinder gas test rig in order to verify the functionality and reliability of the ME-GI concept. The establishment of the gas research platform also required considerable preparations in order to achieve authority approval of the gas supply installation, which was established according to EU’s ATEX regulations (e.g.Directive 94/9/EC, concerning equipment and protective systems intended for use in potentially explosive atmospheres). The ATEX regulations required for example risk analysis, zone classification plans and education of engineering staff. The engine tests performed can be divided into a two groups. Firstly, the ME-GI engine is benchmarked directly against operation on liquid diesel oil. This benchmark confirms a significant reduction in NOx emission. The NOx reduction exceeds 25% on average, which is consistent with simple theoretical estimates based on adiabatic flame temperature equilibrium NOx predictions, where the main driving force is a lower flame temperature due to a higher stoichiometric air amount for methane compared to diesel. Secondly, in order to explore the possibility of even further optimisation of the ME-GI concept a more elaborate study, applying theory from Design of Experiment (DoE) as well as Response Surface Methodology (RSM), is conducted, in which parameters related to the gas injection system are included as well. It is demonstrated that the ME-GI concept offers potential SFOC savings of 3-6 g/kWh in the part load range (below 85% engine load). The engine test data are furthermore supplemented with results from optical diagnostics.