November 22, 2024
Ahmad Reza Kohansal

Ahmad Reza Kohansal

Academic Rank: Assistant professor
Address:
Degree: Ph.D in Marine Engineering
Phone: 07731222181
Faculty: Faculty of Engineering

Research

Title
Investigation of the effect of water depth on the hydrodynamic characteristics of fast floating
Type Thesis
Keywords
آب كم عمق ، شناور پروازي ، تريم ، سطح خيس ، مقاومت
Researchers mohsen hamasi (Student) , Ahmad Reza Kohansal (Primary advisor) ,

Abstract

When the vessel enters shallow water, its dynamic components change fundamentally. The most important of these effects is the occurrence of squats, which are a combination of dents and trims. This phenomenon, which occurs due to the reduction of pressure under the body, especially in the heel area, can have important effects, including a sharp increase in resistance and even floating mud. Since shallow water operations in ports, waterways, lakes and rivers are mandatory for many vessels, it is necessary to predict the hydrodynamic behavior of the vessel in these conditions. In several studies, the effects of shallow water non the behavior of displacement vessels have been investigated both experimentally and numerically. The increasing use of flying vessels as well as the complexity of their hydrodynamic behavior relative to moving vessels provide a good incentive to study this issue. Performing a physical model tensile test in shallow water conditions is one of the ideas of the study, which is possible for several reasons such as complete dynamic dissimilarity between the model and the original sample, high cost and time of execution and difficulty of accurate flow study during the test. Lack in the early stages of design will create problems for designers. On the other hand, there are no reliable experimental relationships to predict the behavior of floating in shallow water, especially for fast vessels. In this dissertation, we have tried to determine the values of resistance, trim and wet surface of the flying hull in open water modes, unlimited shallow water and in the last step in limited shallow water mode (shallow channel) at speeds of 0. 5, 4.75 and 9 meters per second to be examined and calculated. Flying float simulation in the above situations has been done with the help of Star ccm software. In the final stage, using the experimental design method, the results obtained from the simulation with the help of Design Expert program in the form of a separate