Wave Drag: Is it the Same as Fluid Resistance?

AI Thread Summary
Wave drag and fluid resistance are distinct concepts in fluid dynamics. Wave drag refers specifically to the energy lost in creating waves when an object moves through a fluid, while fluid resistance, or skin friction, is the result of the fluid's interaction with the surface of the object. A fully submerged object experiences less wave drag compared to a partially submerged one, but skin friction remains constant regardless of submersion. Understanding the differences between these forces is crucial for accurate calculations in naval architecture and fluid mechanics. The discussion highlights the complexities of drag forces in different scenarios.
Raparicio
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Dear friends,

I'd like to know if the meaning of "wave drag" is the same that the resistance of a fluid.

best reggards.

r. aparicio.
 
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I haven't heard of that specific term. They may be referring to the effects of a wave and it's interactions with the surfaces of two fluids, i.e. Froude Number and boat hull drag calculations.
 
FredGarvin said:
I haven't heard of that specific term. They may be referring to the effects of a wave and it's interactions with the surfaces of two fluids, i.e. Froude Number and boat hull drag calculations.


Dear FredGarvin,

I've read it referent to a boat in surface. My question is that if this could happen, i.e. a submarine, or not (one force due to friction and another due to wave drag) or if two are the same.

best reggards.
 
This is out of my area, but I believe that a fully submerged body does not produce as much wave drag as a partially submerged one. However, the form drag of the body does come into play more.

Skin friction and wave drag are not the same thing. You will always have skin friction no matter what you do. That is due to the interaction of the fluid with the surface of the hull. Wave drag is due to the energy lost to make a wave.
 
FredGarvin said:
Skin friction and wave drag are not the same thing. You will always have skin friction no matter what you do. That is due to the interaction of the fluid with the surface of the hull. Wave drag is due to the energy lost to make a wave.

... One is about Stoke's equation, and the other is much complicated, but I don't know if, for an object into fluid, there are this two or only Stokes's one.

Best reggards (interesting picture, your avatar!)
 
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