Performance Of Marine Diesel Engine Research Articles

Application of artificial neural network for prediction of marine diesel engine performance

This study deals with an artificial neural network (ANN) modelling of a marine diesel engine to predict the brake power, output torque, brake specific fuel consumption, brake thermal efficiency and volumetric efficiency. The input data for network training was gathered from engine laboratory testing running at various engine speed. The prediction model was developed based on standard back-propagation Levenberg-Marquardt training algorithm. The performance of the model was validated by comparing the prediction data sets with the measured experiment data. Results showed that the ANN model provided good agreement with the experimental data with high accuracy.

Thermodynamic Analysis of Ethanol Diesel-Oil Alternative Fuel

For the purpose of providing a scientific reference for improving energy conservation and performance of marine diesel engine, the thermal balance analysis and exergy balance analysis and emission research on ethanol diesel-oil alternative fuel of the existing diesel engine are performed. All necessary data are obtained from an actual diesel engine of KTA50-M2 which is used in a boat located in Dalian. The result shows that engine performance parameters are of no big change, however, the exhaust emissions are significantly reduced.

Formation of Colloidal Shells on Acidic Droplets Undergoing Neutralization in Marine Diesel Engine Cylinder Oils

In this study, a novel colloidal shell formation phenomenon was observed when sulfuric acid droplets underwent neutralization in marine cylinder lubricant at 115 ± 5 °C using heating microcapillary videomicroscopy. Immediately upon injection, shells formed, wrapping the acidic droplets and detached slowly afterward. Shells were optically transparent, about 2 μm thick, and strongly cohesive and rigid since they could deform the contained acid droplet into a non-spherical shape. Shell surface is most likely hydrophobic since the acid droplets did not wet it. It is thought that these shells were made of hydrated calcium sulfate nanoparticles embedded within an organic matrix. This material was presumably formed when oil additives reacted with sulfuric acid right upon exposure. The discovery of this shell formation, which has not been previously reported in the literature, could be important since these shells could be precursors in the formation of well-known deposits found in diesel engine cylinder liners such as “liner lacquer” or “bore glaze,” which impact negatively the performance of marine diesel engines.

Study of Coefficient Effects of Excess Air on Combustion Performance of Marine Diesel Engine

The purpose of this study is to investigate the effect of the coefficient of excess air to the performance of engine. Through a series of the sea trials for newly built ships, the factors that have a great influence of engine’s performance are determined. In addition, methods of raising the coefficient of excess air are proposed to reduce the thermal load and accordingly enhance the performance of diesel engine. Finally, to achieve an efficient operation of the main engine, an example of trouble shooting and maintenance of the engine is given for practical applications. The scavenging pressure increased from 0.162 MPa to 0.207 MPa and the average exhaust temperature dropped from 423°C to 336°C under 90% load condition.

선박용 디젤기관의 열화성능 예측에 관한 연구

Abstract: The higher energy efficiency for ship and the lower pollution for global environment are re-quired strictly. However the performance of marine diesel engine is gradually deteriorated with time. And also the operation condition is varied with sea conditions. Hence the optimization for operating con-dition of marine engines is needed for energy saving and environment kindly. In this paper, it was attempted to investigate the influence of aging for marine diesel engine. The dete-rioration of engine performance is assessed by the calculation results of the simulation program for two-stroke marine diesel engine developed by author which was reported before. And three parameters for deterioration of engine performance were considered such as lower efficiency of turbocharger by fouling, increase of blow-by gas due to wear of cylinder liner and getting worse of combustion by poor injection. By the results, it was shown that the influence of engine performance by aging was relatively not so small - 10.4 bar low in Pmax and 3.2% decrease in Pmi.

Prediction of marine diesel engine performance under fault conditions

The diesel engine, due to its superior efficiency when compared to other thermal engines, is widely used for propulsion of marine vessels. Since in such applications the power concentration is critical, most marine diesel engines are of the turbocharged type. Turbocharging has a serious effect on engine performance due to the interaction between the turbocharger and the engine. This interaction makes the detection of engine faults extremely difficult since a specific fault affects the turbocharger and through it the engine. For this reason various methods have been proposed for the detection of engine faults. The present author has in the past presented a method for marine diesel diagnosis by processing measured engine data using a simulation model. In the present work a completely different approach is followed; an attempt is made to use a simulation model to predict marine diesel engine performance under various fault conditions. The method is applied to a newly built vessel powered by a slow speed two stroke marine diesel engine. Using the engine shop trial data obtained under propeller law the simulation model constants are determined, using an automatic method that has been developed. The comparison of results obtained with the data from the official shop trials confirms the accuracy of the model and its ability to predict almost all operating parameters of the engine. The model is then used to produce results by simulating various engine faults or faults of its subsystems. From this analysis their impact on various measurable engine parameters is determined. It is interesting to see that in the case of turbocharged engines some faults have a different effect when compared to naturally aspirated ones. Also, it is revealed that without the use of modeling in many cases it is relatively difficult to determine the actual cause for an engine malfunction, since the observed effects on engine performance are similar. The proposed method is promising and assists the engineer to understand the actual effect of various faults on engine performance. Also it can be used as a training tool since it is easy to simulate various engine faults, a procedure which is extremely difficult, if not impossible, to perform on the field.

視覚教育訓練支援システム

The IEM VENUS is designed for the trainees and engineers in shipping world to learn fundamental knowledge and basic operation know-how of machincry system in engine room visually, theoretically and practically. The system supports the engineers to achieve the skills mentioned below, without purchasing expensive actual machines. Moreover, the system can simulate variety of diesel engine operations, safely and easily by means of the diesel engine simulator, COMLEX.The basic requirements of technical skill to keep safe operation, which is expected for those who are in charge of ship's engine room are as follows;•Engineers must understand machiner'y function, structure and performance.•Engineers must understand the functional relations among the machinery.•Engineers must read a performance curve of individual machine and system.•Engineers can hold a consultation with a shore support people and manufacture about technological matters.•Engineers can evaluate a machinery's shop test performance.•Engineers can give a proper guide to the crew.•Engineers can process a report of performance data.The system offers;1) Engineers can understand machincry basic function, mechanism and structure visually. Fundamental performance curves which engineers study form to judge machinery condition and carry maintenance work properly are illustrated and explained.2) Typical system piping diagrams which are classified into three layers by functions i.e. basic, stand by, automatic and safety functions to understand step by step are illustrated and explainted as well as actual piping diagrams.3) The system allows engineers to understand tangibly marine diesel engine performance by the diesel engine simulator, “COMLEX”.