Divergence average theorem

Averaging Eq. (8) over the domain Q and use of divergence theorem gives... 

Space averages of e also may be defined by integrating over a fixed volume V of the chamber. Use of the divergence theorem in equation (12) shows that... 

A special case of (3.128) is the theorem for the volume average of a divergence ... 

The divergence theorem finds use in the derivation of the virial. Consider the motion of a collection of particles. To the ith particle a force F is exerted at some position r . The sum over each particle of the scalar product is the virial J2i r, F [19, p. 129]. The time-averaged virial is equal to the average kinetic energy... 

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