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Q: Why does the ST_EXFORCE command report drift forces which do not look correct? REV 5.08 A: What you are getting with ST_EXFORCE is not wave drift, but first order wave excitation. You can look at wave drift raos in the Hydrodynamics Menu with V_MDRIFT…

Q: Why do my "Wave Drift" forces look strange? REV 7.05 A: You do not have a good panel model for diffraction. Remember, the drift force depends on the gradient of the velocity potential while the first order forces depend only on the potential. Thus…

Q: When using #TANKER why do I sometimes get current and wind forces in a direction opposite of what I expect? REV 5.03 A: This is a function of the OCIMF data. #TANKER uses the curves proposed by the Oil Companies International Marine Forum (OCIMF…

Q: Can MOSES compute wave induced shear force and wave induced bending moment on a ship in the frequency domain? REV 5.07 A: Yes, but perhaps not in the way you think. Other programs that deal with only monohull ship structures may provide this in their…

Q: What is the meaning of the "wave force" I get when I issue the &STATUS FORCE command? REV 7.00 A: The result of all &STATUS command are applicable to the current, static, condition. As a result, the "wave force" is the mean drift force and the "drag…

Q: Can I get MOSES to give me a correct wave force on a tank setting on the sea bottom? REV 6.01 A: Actually, you need to do nothing. MOSES automatically eliminates all panels below the mud line. Just make sure that the tank extends below that bottom…

Q: Why does the force I computed on some cargo using the motions and the accelerations not agree with the MOSES force. REV 7.00 A: The answer to your question is a word, phasing . MOSES computes the forces correctly accounting for phasing: i.e. fx…

Q: I have cargo placed symmetrically about the barge centerline. Why do I get very different vertical forces for the port and starboard cargo when I look at the results for a 90 degree heading? REV 7.00 A: This is due to the heave/roll phase relationship…

Q: I am looking at MOSES results from the output report "CARGO G FORCE STATISTICS". Do these G forces include the g*sin(theta) effect? If so, how can the Longitudinal G force be reported as less than half of g times the maximum pitch angle? REV 7.00 …

Q: Is the static angle due to wind included in the "Cargo Force Statistics"? REV 7.01 A: No, it is not. Neither is the static component of gravity. (Notice that the heave force is around .1 to .3 instead of being greater than 1) The manual clearly states…

Q: How can I compute the Cargo Forces on many points and how can I find the maxima for different periods and headings? REV 7.01 A: The quickest way to do this is with loops. This file shows how to report forces for a set of points and how to report…

Q: How are the allowable force AF(1), AF(2) used for the GSPR and LMU connector classes? REV 7.00 A: The same way they are for any connector - they are only used to convert a force into a utilization - the force divided by the allowable.