Optimization of automatic control of the speed of rotation of a marine diesel engine

Annotation – The well-established method of tuning the speed governors (SG) of diesel engines during their operation under conditions of step disturbances, which are characteristic of diesel-generators, cannot be used for the main marine engines, the dynamic modes of which are associated, first of all, with heavy seas, because disturbances cannot change stepwise both along the channel for setting the rotational speed and along the load channel. In this regard, the practical need for the development of a method for tuning the SG of the main engines, which takes into account the peculiarities of their operation in heavy seas, has been determined. The study simulates the automatic speed control system (ASC) of the main marine engine HYUNDAI – MAN B&W 6G70ME-C9.2 of the large crude carrier "GOLDWAY" with the AutoChief 600 electronic SG. The minimum of instability of the controlled parameter was used as an optimality criterion, i.e. the amplitude of the oscillations of the rotational speed of the diesel engine shaft, with the most probable values of the amplitude and period of oscillations (rolling) of the disturbing effect. The study has established that changing the tuning parameters of the governor may lead to local extrema of the optimality criterion when using an electronic governor in the ACS in the factor space of disturbances on a diesel engine, which are typical for heavy seas. It means that the task, requiring finding local extrema using specialized methods, can be set when using an electronic governor in the ACS. However, a significant decrease in the instability of the rotational speed was achieved by carrying out a simple enumeration of the tuning parameters of the SG. It was also found that with a "heavy" propeller, the rotational speed stability can be increased by decreasing the proportional gain, as well as increasing the integrator time.

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Method for assessing the technical condition of marine diesel engine driving the synchronous generator

Combustion Engines ◽

10.19206/ce-2019-225 ◽

2019 ◽

Vol 177 (2) ◽

pp. 139-144

Author(s):

Tomasz KNIAZIEWICZ ◽

Marcin ZACHAREWICZ

Keyword(s):

Diesel Engine ◽

Rotational Speed ◽

Synchronous Generator ◽

Technical Condition ◽

Marine Diesel Engine ◽

Phase Voltage ◽

Working Process ◽

Working Cycle ◽

Marine Diesel ◽

Speed Fluctuation

The paper presents an innovative method for assessing technical condition of a marine diesel engine that drives synchronous generator. It is based on the measurement and analysis of generators phase-to-phase voltage. Additionally, it requires the measurement of a pseudoperiodic signal [3] with a period equal to duration of engines working cycle. The basis for developing method was the assumption that rotational speed fluctuations of an engines crankshaft (and also the generator) depend on a course of a working process carried out in it. The generators phase-to-phase voltage is directly dependent on a rotational speed fluctuation of its rotor. It must therefore be possible to assess a course of a working process of an engine based on a voltage waveform of a synchronous generator that cooperates ogether.

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Model tests of a marine diesel engine powered by a fuel-alcohol mixture

Combustion Engines ◽

10.19206/ce-143486 ◽

2021 ◽

Author(s):

Marcin Zacharewicz ◽

Tomasz Kniaziewicz

Keyword(s):

Mathematical Model ◽

Diesel Engine ◽

Alternative Fuels ◽

Fossil Fuels ◽

Diesel Oil ◽

Marine Diesel Engine ◽

Engine Model ◽

Marine Engines ◽

Marine Diesel ◽

The Mathematical Model

The paper presents the results of model and empirical tests conducted for a marine diesel engine fueled by a blend of n-butanol and diesel oil. The research were aimed at assessing the usefulness of the proprietary diesel engine model in conducting research on marine engines powered by alternative fuels to fossil fuels. The authors defined the measures of adequacy. On their basis, they assessed the adequacy of the mathematical model used. The analysis of the results of the conducted research showed that the developed mathematical model is sufficiently adequate. Therefore, both the mathematical model and the computer program based on it will be used in further work on supplying marine engines with mixtures of diesel oil and biocomponents.

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A Study on Reasonable Ratios of Vegetable Oils and Diesel Oil in Mixed Fuel Used as an Alternative Fuel for Marine Diesel Engines in Vietnam

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.889.244 ◽

2019 ◽

Vol 889 ◽

pp. 244-253

Author(s):

The Nam Tran ◽

Van Uy Dang ◽

Dai An Nguyen

Keyword(s):

Diesel Engine ◽

Vegetable Oil ◽

Fuel Mixture ◽

High Viscosity ◽

Diesel Oil ◽

Negative Effects ◽

Injection Process ◽

Straight Vegetable Oil ◽

Marine Engines ◽

Marine Diesel

Vegetable oil is used directly as a fuel, in either modified or unmodified equipment, it is referred to as straight vegetable oil (SVO). SVOs have some advantages in comparison with fossil fuel oils such as: renewability, local availability, lower sulfur content, etc. avoiding the environmental effects caused by sulfuric acid, lower aromatic content and high biodegradability. However, SVOs are also attached to several disadvantages such as: high viscosity, low heating value, high fatty contents, influencing on injection process and causing engine coking if misused. In order to prevent such negative effects of diesel engine fuelled by SVO, one of potential solutions is using blends of SVO with diesel oil (DO). In such case, the reasonable ratio of SVO and diesel oil plays a very important role for normal running condition, but also seems to be challenge to identify. The article shows results of a study on defining the ratio for marine diesel application. It is firstly based on the assessment on the heat release processes inside the diesel engine cylinder upon a specific simulation with different blends of SVO and diesel oil. In comparison with the particular requirements for fuel of marine engines, the preferable percentage of vegetable oil in the fuel mixture is pointed out. And finally, the experiments with fuel system of a typical marine diesel engine, HANSHIN 6LU32, installed at the lab of Vietnam Maritime University in terms of checking real engine’s operation and reducing harmful emissions.

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Numerical and Experimental Research on Thermal Insulation Performance of Marine Diesel Engine Piston Based on YSZ Thermal Barrier Coating

Coatings ◽

10.3390/coatings11070765 ◽

2021 ◽

Vol 11 (7) ◽

pp. 765

Author(s):

Chun-Guang Fei ◽

Zuo-Qin Qian ◽

Jie Ren ◽

Xiang-Jun Zhou ◽

Si-Wei Zhu

Keyword(s):

Diesel Engine ◽

Ceramic Coatings ◽

Atmospheric Plasma ◽

Marine Diesel Engine ◽

Barrier Coating ◽

Marine Engines ◽

Marine Diesel ◽

Long Time ◽

High Temperature Erosion ◽

Insulation Performance

Although YSZ ceramic coating has been used in the field of aeroengines for a long time to protect blades from high temperature erosion, its application on marine engines is still very rare. In this study, YSZ powder was sprayed onto the upper surface of the Al-Si alloy piston by atmospheric plasma spraying. The piston with or without ceramic coatings was applied to the diesel engine bench, and the ship propulsion characteristics test was carried out to study the effect of the coating on the performance of the diesel engine when the ship was sailing. The temperature field results show that under 25% load, the temperature of the top surface of the coated piston is about 30.91 °C higher than that of the conventional piston. The increase in the temperature of the combustion chamber is conducive to better combustion of the fuel in the cylinder of the diesel engine. Therefore, when the marine diesel engine is tested for propulsion characteristics, the thermal efficiency is increased by 5% under the condition of 25% load.

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Modeling Of The Dependence Of The Produced Amount Of Hydrogen Gas (Y) On The Amperage Of Cell (X) Of A Marine Diesel Engine Skl 3Nvd24

Pedagogika-Pedagogy ◽

10.53656/ped21-6s.24mod ◽

2021 ◽

Vol 93 (6s) ◽

pp. 273-278

Author(s):

Hristo Hristov ◽

◽

Ivaylo Bakalov ◽

Bogdan Shopov ◽

Dobromir Yovkov ◽

...

Keyword(s):

Experimental Data ◽

Diesel Engine ◽

Hydrogen Gas ◽

Sufficient Information ◽

Maritime Transport ◽

Marine Diesel Engine ◽

Marine Engines ◽

Marine Diesel ◽

Marine System ◽

Overall Efficiency

The introduction of new fuels in the field of maritime transport is considered a serious challenge due to the harsh environmental conditions in which the motor ship must operate. Modern marine engines are designed to improve the overall efficiency of the marine system so any attempt to exploit a new fuel must be accompanied by scientific research and experimental data to provide engineers and ship operators with sufficient information on its efficiency and safety.

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Instantaneous Rotational Speed Algorithm for Locating Malfunctions in Marine Diesel Engines

Energies ◽

10.3390/en13061396 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1396 ◽

Cited By ~ 2

Author(s):

Damian Kazienko ◽

Leszek Chybowski

Keyword(s):

Diesel Engines ◽

Rotational Speed ◽

Combustion Process ◽

Diagnostic System ◽

Diagnostic Algorithm ◽

Technical Condition ◽

Practical Implementation ◽

Correct Operation ◽

Marine Engines ◽

Marine Diesel

This article suggested broadening the standard methods for diagnosing the technical condition of diesel engines to include an analysis of the instantaneous rotational speed of compression combustion engines with the use of a novel algorithm. The authors revised the subject concerning the use of the analysis of instantaneous changes in the rotational speed of an engine when assessing its technical condition and the location of the malfunction. An algorithm and its practical implementation in a prototype diagnostic system called SpeedMA were presented. This article reported the test results of the prototype in the context of indicating the engine cylinder in which ignition failed to occur. Tests were carried out for two marine engines: a low-speed trunk engine directly driving the fixed-pitch propeller and a medium-speed trunk engine driving the alternator. For each case, an analysis was carried out for different engine loads and at individual cylinders in which combustion failed to occur. The experimental results showed an unambiguous relation between the combustion process of the examined engines and changes in the instantaneous rotational speed. The results also confirmed the usefulness of the proposed method and showed the correct operation of the presented diagnostic algorithm. The proposed diagnostic system could be used during the operation of engines running in real ship engine rooms.

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Assessment of the technical condition of a marine diesel engine based on the analysis of the exhaust gases chemical composition

Combustion Engines ◽

10.19206/ce-2019-221 ◽

2019 ◽

Vol 177 (2) ◽

pp. 122-126

Author(s):

Rafał KRAKOWSKI

Keyword(s):

Diesel Engine ◽

Technical Condition ◽

Test Methods ◽

Technical Diagnostics ◽

Marine Diesel Engine ◽

Exhaust Gas ◽

Exhaust Gases ◽

Injection Pump ◽

Marine Engines ◽

Marine Diesel

In the article, the concept of technical diagnostics in relation to marine engines was characterized. The compression ignition piston engine was presented as a diagnostic object. The next part of the article discusses the composition of exhaust gases with particular emphasis on compounds harmful to the environment. The available test methods for exhaust composition are also briefly described by means indication of the engine and exhaust gas analyzer. The reduction of emission of harmful compounds in the exhaust gases is also described in the article. The main part of the article presents the research object, i.e. the marine diesel engine piston and the exhaust gases analyzer, as well as tests carried out. The tests were performed for the engine in working order and inefficient condition in order to compare them with the simulated damages of injection pump and turbocharger. The article was completed conclusions.

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