Total momentum loss

The total friction loss in an orifice meter, after all pressure recovery has occurred, can be expressed in terms of a loss coefficient, ATr, as follows. With reference to Fig. 10-12, the total friction loss is P — P3. By taking the system to be the fluid in the region from a point just upstream of the orifice plate (Pj) to a downstream position where the stream has filled the pipe (P3), the momentum balance becomes... 

Section IV reviews our more recently developed 4D ether model [102-104], which is based on the premise of the existence of E. Rest mass is associated to a flow of primordial fluid (preons). This novel dynamic concept of mass solves at once several longstanding difficulties two of them are (1) the infinities associated with electric and gravitational fields and (2) the stability of orbits under Coulomb attraction. Indeed, there is a permanent flow of momentum across a particle (source) the momentum flux is occasionally tapped by interaction with a (test) particle. Such process does not change the total momentum flux available at the source hence, there is no loss of potential energy as in the conventional interpretation. The total momentum that crosses a source is, of course, infinite in an infinite time, but the source is always finite. 

This result demonstrates that if two molecules of the same type collide, then there is no net loss of momentum of the molecules of that type (any other result would be rather unexpected). This result is important because it indicates that the total momentum lost by the molecules of 1 depends only on collisions between molecules of 1 and other types of molecules. The rate at which this momentum transfer occurs depends on how frequently these different molecules collide. 

Equation (7.3-13) has been shown to be quite useful in correlating momentum, heat, and mass transfer data. It permits the prediction of an unknown transfer coefficient when one of the other coefficients is known. In momentum transfer the friction factor is obtained for the total drag or friction loss, which includes form drag or momentum losses due to blunt objects and also skin friction. For flow past a flat plate or in a pipe where no form drag is present, //2 = J = Jp- When form drag is present, such as in flow in packed beds or past other blunt objects,772 is greater thanJ, otJ andJ s Jg. 

For heated horizontal channels, Martinelli and Nelson (1948) assumed the total pressure loss is given by the sum of a pressure loss due to friction and a pressure loss due to increased fluid momentum as vaporization occurs. The local two-phase friction pressure gradients in boiling water were calculated using isothermal flow pressure loss data assuming turbulent-turbulent flow. 

The objective is to calculate the non-recoverable (frictional) pressure loss rather than the total pressure drop (which will also contain recoverable pressure drop due,to change in momentum)... 

For a momentum transfer that is smaller than q both plasmon and e-h pair excitations contribute to the full RPA energy loss, though contributions from losses due to the excitation of e-h pairs are very small. For q> q, however, only e-h pair excitations contribute. This is illustrated in Fig. 3, where the total Zj stopping power is separated according to whether losses correspond to momentum transfers below q < qc) or above (q > q ) the critical momentum q. In Fig. 4, the total Zj stopping power is separated according to whether losses come from momentum transfers below q < 2wp) or above q >. /26 ) the critical momentum which is the low-... 

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