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Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University. Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University. Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University. Thanks to Wikipedia. Surface tension force = 4 x Side x 73 milliNewton / metre at 15C
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Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University
Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University
Chia Po Lin EWTEC Lisbon 1995. PhD Thesis Edinburgh University
Thanks to Wikipedia
Surface tension force = 4 x Side x 73 milliNewton / metre at 15C Buoyancy force = Side3x 1000 kilogram /metre3 x g
1% error for a 55 mm cube. One part in 340 for a 100 mm cube
Combined Gravity Capillary
Drag coefficients as a functions of Reynolds number. Hermann Schlichting
300 300,000 Nearly 1000 :1 OK. Then a drop by a factor of 4 at ReN = 500,000
Full scale cylinder diameter 10 metres Full scale wave trough to crest 4 metres Full scale wave period 9 seconds What scale gives Reynolds number of 500,000?
Full scale cylinder diameter 10 metres Full scale wave trough to crest 4 metres Full scale wave period 9 seconds What scale gives Reynolds number of 500,000? 10 :1
Full scale cylinder diameter 10 metres Full scale wave trough to crest 4 metres Full scale wave period 9 seconds What scale gives Reynolds number of 500,000? 10 :1 But drag forces are ~ 1/30 less than inertial forces and 90°out of phase so who cares?
Not understanding ‘off-the-shelf’ components and materials. Because investors give launch date priority over reliability.
What the sea is doing to your part every ~10 seconds What fraction of your parts will fail
MTBF2 = 67.2 days Need mean stress 6.3 times std. deviation to get MTBF = 150 years
Conventional work vessel Pull only. Very slow direction change.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client. Independent operation.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client. Independent operation. Potentially fatal heel induced by work forces.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client. Independent operation. Potentially fatal heel induced by work forces. Winches, cranes and own electrical generation .
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client. Independent operation. Potentially fatal heel induced by work forces. Winches, cranes and own electrical generation . Too heavy to be lifted by container crane.
Conventional work vessel Pull only. Very slow direction change. Needs intelligent heavy lift capability at both ends. Hard fragile skin punctured in tens of millimeters. Fixed wave response not matched to client. Independent operation. Potentially fatal heel induced by work forces. Winches, cranes and own electrical generation . Too heavy to be lifted by container crane. Conventional GPS with precision of tens of metres.
Ideal Installation vessel Push, pull, twist and shear 280 kN in any direction in seconds.
Ideal Installation vessel Push, pull, twist and shear 280 kN in any direction in seconds. Fast connection and disconnection.