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In the present paper presented are the results of prediction of total resistance of inland waterway vessels based on model test data. In scaling the resistance from model to full scale the extrapolation with two-dimensional frictional resistance formulation (without form factor) was applied, combined with different methods of determination of frictional (viscous) resistance coefficient. There were used the equations that include the effect of water depth, with and without account for pressure gradient. It was shown that limited depth of water substantially affects the frictional resistance. The results of example calculations are compared to resistance prediction made using the ITTC 1957 model-ship correlation line. Example calculations take into account the limited depth of water. Depending on the applied method of determination of frictional resistance coefficient the resultant total resistance of inland waterway vessel is higher or lower than the resistance based on the ITTC 1957 correlation line. The effect of water depth depends on the ratio of water depth to ship draught (h/T), on ship speed, and on the composition of a convoy. The extrapolation of resistance was made without including the form factor. Computations are made based on model test data for an inland waterway cargo vessel, for a kombi-type convoy of an inland waterway cargo vessel and a dumb barge, and for a convoy of two dumb barges without a pushboat
In this work was presented an influence of bow form of inland waterways ship and waterway limitations on values of backward current velocity. The analysis was performed on the basis of results of calculations with the use of numerical modeling the flow around ship hull. The applied HPSDK computation system (a computer software developed by these authors) is based on using surface distribution of vorticity to analyze the velocity field and pressure distribution around ship hull. It was proved that the generated backward current velocity exceeded its permissible non-scouring values
By using fully theoretical method the heeling moment due to centrifugal forces has been determined for a small river cruiser in turning manoeuvre. The authors applied CFD software for determination of hull hydrodynamic forces, and open water characteristics of ducted propeller for estimation of thrust of rudder-propellers. Numerical integration of equations of 3DOF motion was used for prediction of ship trajectory and time histories of velocities, forces and heeling moment
In June 2004 took place an inspection trip aimed at assessing current state of the east-west waterway connecting the Odra and Wisła Rivers; during the trip a photographic documentation of the region was made as well. The below presented text contains also some conclusions resulting from the trip
Model tests of propeller performance in bollard conditions, in deep and shallow water, were carried out atShip Design and Research Centre in Gdańsk. Corresponding calculations of propeller performance with ac-count for finite dimensions of canal cross-section were carried out at Wrocław University of Technology byusing their own theoretical model of propeller – hull interaction. The calculations were carried out in modelscale, at the same water depth as in model tests. For given hull form, propeller geometry and canal cross--section the HPSDK computer code was used to calculate wake fraction, as well as propeller thrust, torqueand efficiency. The distribution of pressure on waterway bottom and ship sinkage were also determined
Results are presented of calculations of ship – generated waves during its motion in canal. For the calculations FLUENT software was used. It was demonstrated that ship generates waves which, when approaching canal slopes, may constitute an important factor in deteriorating the banks, and that ship’s wave resistance can be used as an assessment measure of influence of ship motion on waterway. The methods which are based on approximate formulae, are not reliable. The FLUENT software may be applied as a numerical towing tank
These authors performed a set of numerical calculations of water flow around pushed barges differing to each other by bow forms. The calculations were executed by means of FLUENT computer software. Turbulent free-surface flow of viscous liquid was considered. In this paper the calculated values of barge hull resistance split into bow, cylindrical and stern part components, have been compared and presented
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