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lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line STUDY ON THE PREDICTION OF FLOW CHARACTERISTICS AROUND A SHIP HULL 939 Fig. 8 Pressure Distribution on the Keel Line Wake (at the propeller plane) Fig. 9 and 10 show the axial velocity contours (wake) and velocity vectors on the propeller plane for 170,000 TDW bulk carrier and 4,2000 TEU container carrier. It is not easy to make a definite comparison between the measured and the computed results with these figures. Therefore, the radial distribution of mean axial velocity, that is, the circumferentially averaged radial distribution of axial velocity has been prepared, because this information is used in the actual propeller design. It has been found that there are rather big differences between the test results and the computed results which could not be accepted in the practical purpose. the authoritative version for attribution. Fig. 9 Axial Velocity Contours and Velocity Vectors on the Propeller Plane for 170,000 TDW Bulk Carrier

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lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line STUDY ON THE PREDICTION OF FLOW CHARACTERISTICS AROUND A SHIP HULL 940 Fig. 10 Axial Velocity Contours and Velocity Vectors on the Propeller Plane for 4,200 TEU Container Carrier CONCLUSIONS The flow characteristics around a ship hull were investigated through the numerical and experimental methods. For the numerical analysis, four CFD codes (STAR-CD, FLUENT, SHIPFLOW and HMRI) were used. These numerical results were compared with those of model tests. The object 5 ships were actually built in 1990's. In general, the comparison between numerical analyses and model tests showed rather large discrepancies and lack of consistency both quantitatively and qualitatively. Further improvements in the accuracy and the precision of the codes are necessary in order to be used for the practical applications in the prediction of flow characteristics and hull form design. And it is also necessary to know the flow characteristics in the full scale of a ship by the numerical and experimental methods. Among the four selected codes, only SHIPFLOW can treat the free surface effect using the potential flow theory based on the Rankine panel method. Large differences between analyses and model tests were especially shown for wave pattern around the stern of a ship. The effects of the free surface to the flow characteristics around a ship will be more clearly concluded later after further analyses using the free-surface viscous code based on RANS equations. As was mentioned in the Chapter of Introduction, the 2nd and the 3rd stage studies will be carried out based on the results of present study. REFERENCES Choi, J.E., Seo, H.W., Han, B.W., ‘Experimental Study on the Flow around a Full Slow-Speed Ship', Proc. of JAKOM'99, 4th Japan-Korea Joint Workshop on Ship & Marine Hydrodynamics, Fukuoka, 1999. Kim, W.J., Kim, D.H., Van, S.H., “Calculation of Turbulent Flows around VLCC Hull Forms with Stern Frameline Modification”, Proc. of the 7th International Conference on Numerical Ship Hydrodynamics, Nantes, 1999. Larsson, L. (editor), “SSPA-ITTC Workshop on Ship Boundary Layers”, SSPA Publication No. 90, 1980. the authoritative version for attribution. Larsson, L., Patel, V.C., and Dyne, G., “Ship Viscous Flow—Proceedings of 1990 SSPA-CTH-IIHR Workshop”, Flowtech International AB, Gothenburg, Sweden, 1991. Kodama, Y. (editor), “Proceedings of CFD Workshop Tokyo 1994”, Tokyo, Japan, 1994. Van, S.H., Kim, W.J., Kim, D.H., Lee, C.J., “Experimental Study on the Flow Characteristics around VLCC with Different Stern Shape”, Proc. of the 3rd International Conference on Hydrodynamics (ICHD), Seoul, 1998. Van, S.H., Kim, W.J., Yim, G.T., Kim, D.H., Lee, C.J., “Experimental Investigation of the Flow Characteristics around Practical Hull Forms”, Proc. of 3rd Osaka Colloquium on Advanced CFD Applications to Ship Flow and Hull Form Design, Osaka, 1998