A bulldozer, like many building, road, agricultural and other machines and mechanisms has a working unit supporting wheels, tracks or skis. All of them have a late feedback in kinematics scheme. In contrast other the bulldozer in kinematics chart has a late feedback with amplification factor of k >1. Thus insignificant change of position of supporting units or shovel, cause a considerable change in the depth of treatment. Number of research works revealed that this transitions period described by an arc, and a circumference.
Machines. Technologies. Materials.
Vol. 8 (2014), Issue 7
Table of Contents
Transportation of oil and oil products through the pipeline, due to their high viscosity and the paraffin content is technically and technologically complex process. At present, for the purpose of improving rheological parameters of oil, one of the most effective methods consists in its heating in heat-exchange installations to a certain temperature. The degree of improvement of rheological parameters of oil depends on its heating temperature and conditions of subsequent cooling. Heat treatment improves the inlet capabilities of pumps and allows improving the oil transportation process through the main pipes and pipelines.
The given paper dwells on the design procedure of the heat-exchange installation “the pipe in pipe”. Such type of heat-exchanger is characterized by a simple design and low hydraulic resistance, in which the hot heat transmitter is ecologically clean water.
The process of oil heating in heat-exchanger is the process of convective heat exchange, the intensity of which depends on a number of parameters, including the oil density and viscosity, which in turn are the values depending on temperature. On that basis, the paper dwells on the design procedure of the heat-exchange installation (“the pipe in pipe”) that should enable us to ensure the optimal heating temperature and calculation of geometrical sizes of heat-exchanger through mathematical way.
ONE AND THREE-DIMENSIONAL MODELLING FOR PROCES OF CHARGE EXCHANGE IN RECIPROCATING COMBSUTION ENGINEpg(s) 9-16
This paper presents modeling and simulations of an engine. The proper geometry of a bellmouth is examined by using one and three-dimensional modelling and flow simulations.
MODELLING OF REMOTE CONTROL WORKING PROCESS OF CONSTRUCTION AND ROAD MACHINES OPERATED IN AGGRESIVE ENVIROMENTpg(s) 17-19
It is evident from the experience of operating the construction machinery (excavators, bulldozers, loaders etc.) that quite often the machinery and its operators are working under severe conditions. When the operators are at risk, it is advisable to deploy remote process control technologies on the work sites. This is what brings research and development of modern remote control systems to the top of the chart in order to improve the productivity of machinery, enhance the safety and quality of the jobs carried out.
The oil products remain the main contaminant of the Black Sea, as well as of the entire world’s oceans. A main amount of oil is transported by tankers and reloaded in port terminals. 12 per cent of overall marine pollution is the share of transportation, oil congestion and accidents losses. At the Caspian-Black Sea-Mediterranean area there are actively used the Black Sea ports of Batumi, Poti and Kulevi.
A huge damage to the nature is doing by oil spills on the surface of the oceans and seas owing to transportation oil by tankers. These spills are associated with loading and unloading operations as well as with tankers accidents. In this case, the oil spreads as a spot on the surface of the sea.
Problems associated with environmental pollution from the oil spill in the sea, made necessity to develop mathematical models that describe the transportation and transformation processes of oil spills. The proposed mathematical model can be used for prediction of the spread of an oil spill during the process of spreading of oil products on the water surface, and it also enables to take into account the reduction of the area of spill due to the action of sea-surface winds and turbulence of the water surface.
Today global shipping transports over 90% of the world’s commodities in intercontinental traffic. Within the EU,waterborne traffic accounts for more than 90% of foreign and approximately 40% of domestic trade, transfers around 12 billion tons of ballast water across the planet each year. While ballast water is essential for safe and efficient modern shipping operations, it may pose serious ecological, economic and health threats. Trends anticipate an increasing role for global and local shipping in the future Apart from harmful effects such as consequences of shipping disasters, shipping activity exerts other negative influences on the environment; e.g. sea pollution through the discharges of oily water and sewage water from vessels, air pollution from exhaust gases emitted from the vessel’s machinery, pollution of water and marine organisms from toxic protective underwater hull coatings(antifouling paints), and one of the most recent water born concerns – the translocation of harmful organisms and pathogens via ballast water and sediments inside ballast water tanks.
Ballast water is absolutely essential to the safe and efficient operation of modern shipping, providing balance and stability to unla-den ships. However, it may also pose a serious ecological, economic and health threat for sea nature life.The introduction of invasive marine species into new environments by ships ballast water is an issue that does not always receive the public exposure that it merits.
Despite the serious degradation that has already occurred in the Black Sea, studies have indicated that concerted action can both restore and protect the environment. But the problem clearly requires a multi-lateral approach .The introduction of invasive marine species into new environments by ships’ ballast water attached to ships’ hulls and via other vectors has been identified as one of the four greatest threats to the world’s oceans. The other three are land-based sources of marine pollution, over exploitation of living marine resources and physical alteration/destruction of marine habitat. Quantity of ballast water is change depend of ship’s type. The release of ballast water may introduce non-native organisms into the port of discharge.
Black Sea geography contributes to the manifestation of additional environmental risks: these sea or do not have access or have a very limited relationship with the oceans. Pollution from land-based sources is one of the main causes of environmental degradation of rivers and, as a consequence, seas and coastal areas. Pollution from ships and other activities in the seas are another factor contributing to the deterioration of the environmental status of marine waters and coasts.Much of Georgia’s coastal zone is subject to significant anthropogenic pressures, that could be reason of causing the pollution of marine environment.
Torque and speed measurement has always been a great challenge for many industries such as aviation, shipbuilding and automotive industry. These forces are of substantial importance for the research of the deformation processes developing in the modern marine diesel engines. The values of these forces provide the input data for calculating the overall strength of ship power plants. Continuous monitoring of these parameters while the ship is in service ensures safe operation of all machinery, reduces the risk of unplanned repair works and improves the engine performance in view of low fuel consumption and reduction of CO2 and NOx emissions.
In this article has been considered the influence of various pressures in pneumatic tires of passenger cars with anti-lock braking system and without it on chosen parameter of braking process – braking deceleration. The experiments under snow road conditions are carried out. Used tires for the experiments are for winter conditions.
Simulation on single cylinder diesel engine and estimation of engine performance using AVL Boost softwarepg(s) 33-35
The simulation and computational development of modelling for the research is use the commercial Computational Fluid Dynamics (CFD) of AVL Boost software. In this research, the one dimensional (1D) CFD modelling of four-stroke direct injection diesel engine is developed. The analysis of the model is fluid flow and combustion performance process in the engine cylinder. In this model it can to know the diesel engine performance effect with simulation and modelling in any speed (rpm) parameters before to do the physically development, so it can do the new engine design components with the economic material and time. The model simulation covers the full engine cycle consisting of intake, compression, power and exhaust. The simulation result highlighted energetically and economic performance of the engine.
The vibrations caused by road-building machinery affect drivers equally harmful to the three axes of the coordinate system.
Assessment of exposure to vibration hand-arm system is based on the calculation of daily exposure value for the 8-hour A (8).
THE NEW METHOD OF DETERMINATION OF VESSEL WEIGHT AND APPLICATE OF ITS CENTRE OF GRAVITY BY USING OF ELASTIC INFLATABLE TANKSpg(s) 39-40
The new and modified method of experimental determination of the vessel weight and the coordinates of its center of gravity without launching using inflatable elastic containers are shown in this article.