course name: The Principles of Naval Architecture
JEE 504 – Principles of Naval Architecture – Assignment __________________________________________________________________________________ 1 JEE 504 PRINCIPLES OF NAVAL ARCHITECTURE Final Project Date range: 18th May to 08th June 2020 This project forms 50% of the subject’s total marks. This project is in two part (A) and (B). Student’s report is to be submitted on-line (PDF files) __________________________________________________________________________________ Part (A): Hydrostatic Analysis (50%) The offset table of 88.2m bulk carrier is provided, and the main particulars of the ship are as follows: LWL (St.0-15) 84 m BWL (Max) 15.27 m Displacement 4206 t KB 2.055m KG 5.88 m LCG 45.2 m T 3.91 m 1. Using the offset table and associated data, determine the best estimates for the following hull form data at the ship’s design draft (3.91m): BMT, KMT, BML, KML, LCF, TPC and MCTC 2. Draw a GZ curve using the cross-curve given in the 2nd page of the excel offset table, where formulas and GZ table is provided. Investigate if the ship stability complies with the “Criteria regarding righting lever curve properties”, sub-section 2.2 of International Code on Intact Stability, 2008 (IS Code). The IS Code is accessible through IMO Codes from Regs4ships website: (http://dmr.regs4ships.com/australia/) (continue next page) __________________________________________________________________________________ http://dmr.regs4ships.com/australia/ JEE 504 – Principles of Naval Architecture – Assignment __________________________________________________________________________________ 2 Interpretations Required of Students: Provide a concise assessment of the vessel’s probable sensitivities to GZ curve if additional loads are either loaded to or discharged from the vessel during port operation, based on any of the values you have determined above. Guidance for Students: An approach recommended to this part of the project is as follows: 1. Set up a spreadsheet to determine the values required similar to Assignment-1 2. Refer to page two of the excel sheet and read out the GZ values for the given displacement. 3. Correct the extracted GZ value for the given KG since the default value for the GZ table is 6m and complete the GZ table using two formulas give. 4. Draw the GZ curve and check if it complies with the Righting-Lever criteria given in IS-Code. You may need to measure the area under the curve using Simpson’s rules. ________________________________________ Part (B): Structural Analysis (50%) For the midship-frame of the ship given in Part(A), calculate the thickness of plates and section modulus of the stiffeners, webframes and girders. For these calculations, you can refer to “Steel vessels under 90m in length” rules accessible from ABC website: https://ww2.eagle.org/en.html ABS>Rules & Resources>Rules & Guides. 1. Draw a midship frame to include plates, stiffeners, webframes and girders for the bottom shell, double bottom, side and deck plating. 2. Determine the followings, when the ship is subject to a sagging moment of 80 MNn: a) the bending stress at the upper deck edge and lower chine when the vessel heels 15°; b) the angle of heel for which the bending stress is maximum; c) the maximum bending stress occurring in part (b); d) the inclination of the neutral axis at the angle of maximum bending stress. (continue next page) __________________________________________________________________________________ https://ww2.eagle.org/en.html JEE 504 – Principles of Naval Architecture – Assignment __________________________________________________________________________________ 3 Guidance to Students: 1. Set up a spreadsheet to perform scantling (structural calculation) for the midship frame. 2. Prepare a report for the scantling with reference to the sections and equations from the rules, which have been extracted. 3. Perfome the scantling for bottom, double bottom (inner bottom), side and deck. 4. Specify the thickness and section modulus of the plates, frames (stiffeners), webframes and girders. 5. Provide a midship frame drawing with sufficient texts and dimensions. You may draw a half of the midship frame since it would be symmetrical. 6. The following assumptions should be considered: a) The position of double bottom should be determined by ABS rule. b) Use Longitudinal frame spacing for the bottom, double bottom, side and deck. c) The Frame spacing in bottom, side and deck is 600 mm. d) The Webframe spacing in bottom, side and deck is 2400 mm. e) The distance of midship frame from the next and previous bulkheads is 4800 mm. f) Maximum five girders could be set for bottom and deck. Interpretation Required of Students: Given that the midship-frame being designed is subject to maximum bending stress, what limitations would you have suggested for the maximum permanent deflection or any other aspect of the structural design and reasons why? Guidance for Students: Keep your response(s) to this last part (suggestions on limitations) concise. No more than half an A4 page is expected, but if students do want to provide more than that, it would be perfectly acceptable. ________________________________________ __________________________________________________________________________________