• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.123-129
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• 2012

This study was carried out to improve the design of fuel injection pump for marine medium diesel engine. For this purpose, all parts of fuel injection pump were modeled and simulated using CATIA V5R19, FLUENT & MSC Nastran. Flow analysis for plunger cylinder and structural analysis for plunger, roller and spring, which were considered as essential parts of fuel injection pump, were performed to find the optimal design of fuel injection pump. As the results, flow of fluid in plunger cylinder was showed good results in case of 7.7~8.0m/s of plunger velocity. Furthermore, it was confirmed that plunger, roller and spring could be operated safely under 1,800bar pressure.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.6
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• pp.615-622
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• 2010

In this study, a 0D multizone spray-combustion model is developed for the estimation of the performance and NOx emission of medium-sized direct-injection marine diesel engine. The developed combustion model is coupled with the commercial 1D cycle-simulation model, Boost, to analyze the entire engine system, including the intake and exhaust. The combustion model code was generated using Fortran90, and the model was coupled with Boost by connecting the generated code to a user-defined high-pressure cycle (UDHPC) interface. Simulation was performed for two injectors (8 holes and 10 holes) and two engine loads (50% and 100%), and the results of simulation were in good agreement with engine performance test.

• Journal of Ocean Engineering and Technology
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• v.24 no.2
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• pp.47-52
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• 2010

The proper surface pressure on the pistons rings in the diesel engine of a ship is very important, because the pressure controls the oil that is needed to maintain friction at acceptable levels between the pistons and the cylinders. In this paper, basic and theoretical concepts to compute the ring pressure were formulated and applied to obtain the proper surface pressures on selected sample piston rings. During the calculation of the pressure on the piston rings, the computation of the accurate free shape of the piston ring was required. Earlier, Arnold and Prescott introduced theories to compute the free shapes of piston rings, and their approach used rectangular and polar coordinates. In this paper, the free shapes of piston rings using two different theories were computed and compared. The results were quite close, representing the free shape of the piston ring. Ring pressure was computed using the Arnold's free shape that was obtained. A simple GUI was made to compute the surface pressure on the piston rings.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.6
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• pp.914-921
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• 2022

The International Maritime Organization (IMO) has set a goal of reducing ship's carbon dioxide emissions by 70% and greenhouse gas emissions by 50% by 2050 compared to 2008. Shipowners and shipyards are promoting various R&D activities such as LNG propulsion, ammonia propulsion, electric propulsion, CO₂ capture, and shaft generators as a way to satisfy this problem. The dual shaft generator has the advantage that it can be directly applied to an existing ship through remodeling. In this paper, the total fuel reduction rate that can be obtained by applying the shaft generator to the existing ship was verified through simulation. For this purpose, the size of the medium-sized ship was defined, and the governor, diesel engine, propeller, torque switch, generator for shaft generator, propulsion motor for shaft generator, and ship model were modeled and simulated.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.13-14
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• 2005

Multi-dimensional combustion analysis and experiment has been carried out to investigate the effects of the injector nozzle hole diameter and number on the NOx formation and fuel consumption in HYUNDAI HiMSEN engine. The behavior of spray and combustion phenomena in diesel engine was examined by FIRE code. Wave breakup and Zeldovich models were adopted to describe the atomization characteristics and NOx formation. Wallfilm model suggested by Mundo, et al. and auto-ignition model suggested by Theobald and Cheng were adopted to investigate the spray-wall interaction characteristics and ignition delay. The information of spray angle and spray tip penetration length was extracted from fuel spray visualization experiment and the fuel injection rate profile was extracted from fuel injection system experiment as an input and verification data for the combustion analysis. Next, the nine different nozzle configurations were simulated to evaluate the effect of injector hole diameter and number on the NOx formation and fuel consumption.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.545-552
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• 2009

The marine medium-speed diesel engines are operated by two methods; one is the electric motors, and the other air starting motors. Even though air starting motor is dependent of the engine types and sizes, it has been widely used in this area due to its simplicity, convenience and reliability. However most of them are currently imported from overseas due to the lack of the cutting-edge technology in terms of design and manufacturing. Therefore, from the point of this view, the air starting motor needs to be produced by our own techniques. The purpose of this paper is to give the designing parameters in order to make a proper "Air Starting Motor" using CFD. The aerodynamic approaches were given to understand the internal flow characteristics of the air starting motor. In addition, we have carried out the effects of tip clearance. In the calculations the tip clearance of air starting motor has been varied between 0% and 5.7% of blade span.