Download Naval Architecture Homework #3: Calculating Waterplane Area and Coefficients and more Study notes Aerospace Engineering in PDF only on Docsity! Homework #3 LTJG Zachary B. Robertson, USCG Mechanical Engineering M.S. Student DUINS, USCG Marine Engineering, Virginia Tech Naval Architecture, AOE 3204 Professor P. Kumar, Virginia Tech LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH HOMEWORK #3 #1 DEFINE GIVEN: FIND: a) Using the trapezoidal rule, calculate the waterplane area of the vessel. b) Using Simpson’s First Rule, calculate the waterplane area of the vessel. c) Discuss which calculation, either that of part a or part b, you believe is more accurate. d) Calculate the waterplane coefficient using your most accurate estimate of waterplane area. CRITICAL FORMULAS: Trapezoidal Rule: ! ! !" = !! ! !! !!(!!) ! !! !"!′′(!) ! ! Simpson’s Rule: ! ! !" = !! ! !! !!!(!!)!!(!!) ! !! !"! !(!)!!!! CW = AW L*B REFERENCES: [1] Zubaly. “Applied Naval Architecture”. Cornell Maritime. Centreville, 1996. [2] Burden, R. L., and Faires, J. D., 2005, “Numerical Analysis: 8th Edition,” Thomson Brooks/Cole, Belmont, pp. 188-‐192. LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH VERIFY Units are accurate and reasonable. Significant digits taken to 2, due to accuracy of the values at Station 10. Answer is appropriate – and both parts a and b were found to be similar. ENCLOSURES None. LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH HOMEWORK #3 #2 DEFINE GIVEN: Figure 2: Design waterline for simplified hull form. Figure 3: Immersed midship section for simplified hull form. LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH FIND: a) AW b) M∞ c) LCF (Relative to miships) d) I∞ e) IL f) IT g) AS h) CM i) CIT j) CIL CRITICAL FORMULAS: AW = ydx!L 2 L 2" M# = 2 x* y( )dx!L 2 L 2" LCF = x = M# AW I# = 2 x 2y( )dx!L 2 L 2" IL = I# ! AW (LCF) 2 IT = 2 3 y3 dx !L 2 L 2" AS = 2 ydz0 T " CM = AM B*T CIT = 12* IT B3 *L CIL = 12* IL B*L3 REFERENCES: [1] Zubaly. “Applied Naval Architecture”. Cornell Maritime. Centreville, 1996. [2] AOE 3204: Naval Architecture: Class Slides – 20JAN11. [3] AOE 3204: Naval Architecture: Class Slides – 25JAN11. [4] AOE 3204: Naval Architecture: Class Slides – 27JAN11. LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH f) Calculate the transverse moment of inertia. IT = 2 3 y3 dx !L 2 L 2" IT = 2 3 5x ! x 2 50 ! x3 625 # $ % & ' ( 3 dx !L 2 L 2" IT = 2 3 5x ! x 2 50 ! x3 625 # $ % & ' ( 3 dx !50 50 " IT = 2 3 46520 7 ) *+ , -. IT = 93040 21 IT = 4430m 4 g) Calculate the immersed station area at midships. AS = 2 ydz0 T ! AS = 40" 2 4 625 z4 dz 0 5 ! AS = 40"8 AS = 32m 2 h) Calculate the midship section coefficient. CM = AM B*T CM = 12m4( ) 10m( )* 4m( ) CM = 12m4( ) 40m4( ) CM = 12 40 CM = 3 10 CM = 0.333 LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH i) Calculate the waterplane inertia coefficient CIT. CIT = 12* IT B3 *L CIT = 12* 4430m4( ) 10m( )3 * 100m( ) CIT = 53165.7m4( ) 100000m4( ) CIT = 0.532 j) Calculate the waterplane inertia coefficient CIL. CIL = 12* IL B*L3 CIL = 12* 418184m4( ) 10m( )* 100m( )3 CIL = 5,018, 214m4( ) 10,000, 000m4( ) CIL = 0.502 VERIFY Units are accurate and reasonable. Significant digits taken to 2 and 3, dependent on accuracy of given data for each specific problem. Answer is appropriate and of proportion of those found in the 25JAN11 and 27JAN11 class note examples. ENCLOSURES N/A. LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH HOMEWORK #3 #3 DEFINE GIVEN: DD-‐692 Class Length: 383 ft TF = 12’9” TA = 13’3” KG = 16’ FIND: a) TM b) ΔSW c) CB @ Level Trim d) CM e) CW f) LCF (Relative to Midship) g) GM h) KML i) TPI * 1” CRITICAL FORMULAS: TM = TF +TA 2 CB = Displacement _Volume L*B*T Displacement _Volume = ! !g CM = AM B*T CW = AW L*B GM = KM "KG KML = KB+BML REFERENCES: [1] Zubaly. “Applied Naval Architecture”. Cornell Maritime. Centreville, 1996. [2] AOE 3204: Naval Architecture: Class Slides – 27JAN11 – Slides 6-‐16 LTJG ZACHARY B. ROBERTSON, USCG NAVAL ARCHITECTURE (3204) PROFESSOR P. KUMAR, VIRGINIA TECH BML = 478* 200 100 = 956 ft KB = 783* 1 100 = 7.83 ft KML = KB+BML KML = (7.83 ft)+ (956 ft) KML = 963.83 ft KML ~ 963 ft i) After a period of time, the mean draft decreases by 1 inch with the same trim. How many tons of fuel and stores have been consumed? TPI =1402* 2 100 = 28.04 tons in !! =1inx28.04 tons in !! = 28.04tons VERIFY Units are accurate and reasonable. Significant digits taken to 3 and 4, dependent on accuracy of given data for each specific problem. Answer is appropriate and of proportion of those found in 25JAN11 class note examples. ENCLOSURES • USS Gearing DD 710 (692 Class) Curves of Form -‐ Annotated °
°°
c
So
z
Oo
=
c
ce
F
i
i
§
i i ‘i
my
j | a