Examination of the intact stability and the seakeeping behaviour

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6 Detailed examination Table 6.7: Vessel No. 11: Chicago Express alike oating condition Main Value Unit dimensions △ 66649 [t] T AP 9.07 [m] T F P 7.08 [m] T rim -1.99 [m] KM 24.30 [m] KG variable [m] GM solid variable [m] The results listed in table 6.8 show, that Vessel No. 11 at rst does not experience excessive transversal accelerations . However for GM solid = 9.28 m a slightly maximum for the transversal acceleration of 5.5 m /s 2 is already considered to be noticeable. So for this specic sea condition within accident situation 1, a GM solid value of about 9 m leads to the highest, but insignicant accelerations. Table 6.8: Vessel No. 11: Transversal accelerations for CE alike loading conditions Loading GM solid [m/s a t max conditions [m] 2 ] CE Accident 8.54 10.0 no. 11 V1 6.28 3.5 no. 11 V2 8.02 4.5 no. 11 V3 9.28 5.5 no. 11 V4 10.01 5.0 no. 11 V5 10.95 5.0 no. 11 V6 11.89 5.0 Following from this result, another compilation of displacement, trim and GM should be determined, where the constant excitation of the seaway results in high accelerations. For this reason the vessel is immersed slightly deeper. The new oating condition shown in table 6.9 is set. A new compilation of loading conditions is then created by varying GM in the same scope as before. Table 6.9: Vessel No. 11: New oating condition Main dimensions Value Unit △ 80,000 [t] T AP 10.68 [m] T F P 8.69 [m] T rim -1.99 [m] KM 23.53 [m] KG variable [m] GM solid variable [m] The results listed in table 6.10 show, that Vessel No. 11 in accident situation 1 now expe- 54
6.2 Rolling behavior of the large vessels riences signicant higher transversal accelerations on the bridge up to 10 m /s 2 , than within the loading condition summarized in table 6.7. As in the CE alike loading condition, the maximum value occurs for a GM solid of about 9 m. The associated curves for both loading conditions are shown in gure 6.6. For comparison, the situation of the Chicago Express in its accident loading condition is also shown. The results prove the given presumption for Vessel No. 11 to be correct, too. A rather slight variation of the oating condition leads the vessel to the risk of experiencing very high transversal accelerations on its bridge. Therefore all vessels, including the large vessels have an increased risk of accident in the examined seaways. Table 6.10: Vessel No. 11: Transversal accelerations for new loading conditions GM Loading condition solid [m/s a t max [m] 2 ] CE Accident 8.54 10.0 no. 11 V7 6.23 3.5 no. 11 V8 7.97 5.5 no. 11 V9 9.24 10.0 no. 11 V10 9.96 8.0 no. 11 V11 10.90 7.0 no. 11 V12 11.84 6.0 12 Maximum transverse acceleration on the bridge [m/s2] 10 8 6 4 2 0 5 6 7 8 9 10 11 12 GM solid [m] Vessel No.11 in CE accident condition Vessel No.11 in new condition CE in accident Figure 6.6: Vessel No. 11: Variation of GM solid in dierent loading conditions In addition, the curves in gure 6.6 conrm the statement, already given in chapter 5.2. This examination clearly shows, that the problem of high accelerations on the bridge is denitely not a pure stability problem. Here the dierences between the two loading condition sets, listed 55
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Dezember 2010 SCHRIFTENREIHE SCHIFF
Page 5:
1st Examiner: Prof. Dr.-Ing. Stefan
Page 9 and 10:
Contents List of Figures List of Ta
Page 11 and 12:
Contents A.14 Vessel No. 14 . . . .
Page 13 and 14:
List of Figures 2.1 Calculation mod
Page 15 and 16:
List of Tables 3.1 Accident situati
Page 17 and 18:
Nomenclature Symbol Unit Meaning A
Page 19 and 20:
1 Introduction In the years 2008/20
Page 21 and 22: 1.2 Following objectives for the di
Page 23 and 24: 2 Theory 2.1 Description of the uti
Page 25 and 26: 2.1 Description of the utilised sea
Page 27 and 28: 2.1 Description of the utilised sea
Page 29 and 30: 2.2 Environmental conditions period
Page 31 and 32: 3 Data input The thesis is written
Page 33 and 34: 3.6 Free surface correction 3.6 Fre
Page 35 and 36: 3.10 Bridge height 3.10 Bridge heig
Page 37 and 38: 4 Examination For each vessel the s
Page 39 and 40: 4.2 Vessel No. 02 4.2 Vessel No. 02
Page 41 and 42: 4.3 Vessel No. 03 ˆ The documented
Page 43 and 44: 4.5 Vessel No. 05 accident situatio
Page 45 and 46: 4.6 Vessel No. 06 4.6 Vessel No. 06
Page 47 and 48: 4.7 Vessel No. 07 ˆ The stability
Page 49 and 50: 4.9 Vessel No. 09 Figure 4.16: Tran
Page 51 and 52: 4.10 Vessel No. 10 4.10 Vessel No.
Page 53 and 54: 4.11 Vessel No. 11 ˆ The limiting
Page 55 and 56: 4.13 Vessel No. 13 Figure 4.24: Tra
Page 61 and 62: 5 Evaluation Based on the determina
Page 63 and 64: 5.3 Recommendations accelerations s
Page 65 and 66: 6 Detailed examination The evaluati
Page 67 and 68: 6.1 Variation of the GM values acce
Page 69 and 70: 6.2 Rolling behavior of the large v
Page 71: 6.2 Rolling behavior of the large v
Page 75 and 76: 7 Conclusions Summing up the result
Page 77 and 78: A Vessel data A.1 Vessel No. 01 Tab
Page 79 and 80: A.3 Vessel No. 03 A.3 Vessel No. 03
Page 87 and 88: A.11 Vessel No. 11 A.11 Vessel No.
Page 93 and 94: B Variation of the bilge keel area
Page 95 and 96: C Variation of the ship's speed 16
Page 97: Bibliography [1] BSU; Federal Burea
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Examination of the intact stability and the seakeeping behaviour

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