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Asas Maneuvering Modeling Group (MMG)

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source:   MMG 3D philosophy of theory behind MMG : THESIS   ( from p. 39 to 46) This note will explain in brief, simple but sufficient to understand the story behind MMG and how to understand it. Starts with: 1.  Coordinate systems 2.  Motion equations 3.  Hydrodynamic forces - acting on hull, force by propulsion and forces by steering. 4.  Tests for obtaining the coefficients: RFT - in straight moving with B = 0 (  hull drift angle equal 0). OTT - the ship is towed in oblique. (  B is not 0. ).   This OTT is performed with r' = 0  where there is no yawing involved. CMT -  the ship model is kept captive and towed at certain  r'  yawing  rate.  The rate is covered normally from 0.2, 0.6 and 0.8. RFT - in oblique towing and steady turning. This test is to obtain flow straightening coefficient test. ----------------- In calculating hydrodynamic derivatives, LSM is applied. ...
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resistance

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source document :   source : SNAME vol ii components: 1. Frictional resistance: due to motion of hull through a fluid that is its character is viscous 2. wave-making resistance: due to the energy that additionally must be supplied continuously by the ship to the wave system. The so called "wave system" was created on the water surface. 3. eddy resistance: energy that carried away. That energy due to eddies shed from the hull + appendages. 4.  Air resistance. Note :  normally there is another name, which is called as "residuary resistance". It is the combination of wave-making and eddy resistance. 
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how propeller works - impulse theory

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source: file.pdf impulse theory is the most basic to propel a ship in the impulse theory, the pressure is changing. Low pressure is before, and high pressure after blades. And the pressure become stabilized at certain time. ( basic: bernoulli law - pressure velocity stuffs) 
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