Solid State Phenomena Vol. 236

Abstract: Engine operating conditions of the main propulsion, static in principle with steady-state rotation speed of the crankshaft and engine load, also work under dynamic load conditions. These conditions cause additional distortion of the crankshaft and changes in the operating conditions of the shaft bearings. However, the greatest impact on the long and trouble-free operation has proper engine maintenance. Variable operating conditions and engine operating errors, unfortunately, often cause damage to the main bearings of the crankshaft. Repair of the damaged main bearing spindles of the shaft involves performing the machining of the spindle surface then its re-hardening and selecting new bearing bushings with the appropriate bearing clearance. Trusting the engine manufacturer, there is no check of the influence of the machining of bearing spindles on the structural properties of the shaft. Therefore, the paper presents the model tests of the structure of medium-rev marine engine crankshaft aimed at determining the changes in the mechanical properties of the structure resulting from carrying out the regeneration of the main shaft spindles.

Abstract: Corrosion is an everyday occurrence. It provokes the materials destruction, what directly translates into the durability, survivability and reliability of the equipment, specially of working in the aggressive environments one – e.g. afloat ships or boats. Corrosion is a cause of growth of the requirements of the raw materials needed for production of more and more new products and increase amount of waste come from this production.In the paper authors show the results of the experimental tests and they describe the meaning of the selection of laser bean parameters oriented for surface of chosen steel exposed to even corrosion.

Abstract: This paper defines factors determining the values of electrical energy fluxes required by chosen bulk carriers and specialized ships. Relations between these factors and unique specifics of offshore type vessels have been pointed out. Basing on the compiled lists of similar vessels, using regression and determination coefficient, the strength of Pearson’s linear correlation between the total power of the main power system of particular types of ships and the required installed electrical energy was determined. The obtained relations were graphically correlated with each other revealing special qualities significant for the operation of offshore vessels, different than for other types of ships.

Abstract: The most commonly used starter batteries for ship engine rooms are lead acid systems. Lead acid batters have the lowest electrochemical parameters from all other modern electrochemical systems. On the other hand their biggest advantage is the price of the cell which is much lower comparing to other electrochemical systems. Due to fact that the lithium – ion batteries are very widely used and constantly developed this technology is starting to be promising as an alternative for lead acid batteries for starter applications. Because of this there is a need to verify if the lithium - ion technology can be used for start-up and power backup systems and how will it affect the construction of the engine room and those systems. In order to determine the potential energetic requirements during the design of starter systems in an backup engine room with the use of lithium – ion batteries, in the article the analytic of their performance was conducted with comparison of other electrochemical systems.

Abstract: The paper presents a model of dynamics of six-cylinder inline diesel engine executed in the Matlab software. The basic equations necessary to describe the forces acting during the engine operation was presented. Application of some simplifications allowed to present proposal of a mathematical model of the engine, which allows analysis of changes of forces in the crank-piston system, depending on the technical condition of the fuel system elements. Operational experience indicate that one of the most common cause of failure of the fuel system is reduced fuel charge supplied by a defective fuel injection pump. Calculations of gas forces had been replaced by the implementation into the model indication charts recorded from tests on a engine test stand. Simulation results were presented as a result of FFT spectra of modeled tangential forces.

Abstract: In the paper, the problem of modeling motion of Biomimetic Underwater Vehicle BUV has been taken into consideration. The model of the BUV motion has been designed for initial tuning and verification of the vehicle’s autonomy system. The BUV is built within development project funded by Polish National Centre of Research and Development. At the end of the project, it is expected to achieve technology demonstrator at the 7th level of technology readiness.In the first part of the paper, a control-oriented mathematical model of the BUV designed for implementation of the simulator is described. Then, selected results of the BUV operation in the form of courses of the vehicle motion parameters are presented. Finally, general information about the implementation of the BUV model has been inserted.

Abstract: In this paper, game and optimization theory is applied to the marine navigation in congested waters. The process of game ship control is mentioned first, and then the base model and the approximated models are described with the simulation results. For each approximated model of the dynamic game, an appropriate method of safe control to support the navigator decision in a collision situations has been assigned. The considerations have been illustrated an examples of a computer simulation of several algorithms to determine the safe ship's trajectory in situations of passing many of the ships encountered, recorded on the radar screen in real navigational situation at sea.

Abstract: The aim of this study was to design an moving object detection, localization and tracking algorithm able to detect, localize and track especially humans and vehicles. We focused on triangulation techniques to calculate the position of the detected objects in a stereo vision rig coordinates frame. For objects detection and tracking the novel algorithm, based on statistical image processing methods, was proposed. Verification of a proper operation of the elaborated method was made by conducting series of experiments. Our results indicate that the algorithm localizes, detects and tracks objects accurately for the most tested conditions.

Abstract: The article presents an example of research results of the mechanical vibrations of the internal combustion engine with a viscous torsional vibration damper of the crankshaft for different values of the viscosity of silicone oil. A comparison of the crankshaft torsional vibration and the transverse vibration motor body was made. There was proposed the use of the information contained in the transverse vibration signals in order to determine the changes in the technical condition of the viscous damper (changes in viscosity of silicone oil fillingthe damper). Accepting the argument which assumes that there exists the coupling vibration and torsional shaft bent in transverse vibration signals, there should appear symptoms associated with changes in the torsional vibrations. In order to prove this thesis there was conducted active research experiment. Measurements of transients during engine acceleration were made. There was presented the example of the results of measurements of the crankshaft torsional vibrationand the transverse vibration of the motor body.

Abstract: Combustion engines are the components of means of transport which during service are exposed to the occurrence of excessive clearances. The diagnosing of the condition of the engine requires developing methods which could be useful during both continuous and single checks of the engine. Application of measurements and acoustic signal processing may facilitate a quick diagnosis of the engine without any additional disassembly work. As part of the study, research was conducted to develop a non-invasive method of diagnosing excessive clearance of the combustion engine. Based on the recorded acoustic signals of the combustion engine and reference signals of the momentary crankshaft position, a method was developed to diagnose an increased valve clearance in the combustion engine. In this method, processing of the recorded acoustic signals by means of the continuous wavelet transform was applied together with a comparison of their instantaneous energy, depending on the crankshaft rotation angle and timing angles, as well as the scale parameters of time and frequency distributions.