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Mechanical equilibrium of fluids
This equation places a restriction on the body forces. Mechanical equilibrium can exist only if…
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The balance of entropy
The entropy is a thermodynamic variable of state; an extensive quantity. It cannot be experienced…
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The principle of conservation of energy
Any material system is characterized by its energy content. Energy occupies a position of distinction…
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The balance of kinetic energy
Let Ek denote the kinetic energy of a material volume: Although the kinetic energy is an extensive…
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The balance of angular momentum
The principle of conservation of angular momentum belongs to the axioms of mechanics. In spite…
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The balance of momentum
Newton’s second law of motion is perhaps the most important statement in the field of…
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The transport theorem
The material derivative of a volume integral over a volume of flowing fluid
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Relationships between the acceleration- and the vorticity fields
Important relationships can be obtained for the fluid flow by examining some of the obvious…
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Rotational motion, vorticity field
In order to illustrate this concept, we consider a typical fluid element of certain volume…