Local pressure loss coefficient

Where F ELi/Ai. It is also possible to absorb the local pressure loss coefficient, Ki into an equivalent length, Lci such that Ki=fiLci/Di. With this correction, the momentum equation can be written as ... 

The spacer grid in a rod bundle is also a turbulence promoter that enhances liquid-vapor exchange and bubble condensation. The local intensity of such turbulence is a function of the grid pressure loss coefficient, K, and the distance from the grid, t D. Thus an empirical spacer factor, Fs, can be defined as... 

Some of the structural factors, such as the changes in cross section area of flow passage and flow direction etc., may also cause pressure losses. Obviously, these factors depend on the specific structure of the device under consideration and vary from device to device. For convenience, and for more generalization, the resistance resulting from all the structural factors is represented in terms of the combined local resistance coefficient, 1s, which is also related to the velocity of the gas flow in the accelerating tube, i.e., the impinging velocity, utl. i.e.. 

Hydraulic resistance of centrifugal machines is generally viewed as the local resistance. Hydraulic resistance coefficient, pressure losses in the unit determined experimentally and are mainly as a function of the geometry and the Reynolds number [9]. 

By analogy with flow of water alone it is possible to introduce a coefficient of local resistance also for capsules flow and to define total pressure losses in a bend as the sum of friction losses in the straight pipe, he, and local losses in the bend... 

The first term on the right-hand side of Equation (6-12) represents the energy decrease along the streamline in the manifold due to velocity loss the second term is the pressure drop due to friction with the walls,- and the last term is the pressure loss due to local disturbances described by the geometric coefficient. 

The water photolysis under low O2 pressure always led to a loss of hydrogen into space. The diffusion rate of the H2 (or H after it has been broken down by photolysis) through the homopause and exobase is limited. The definition of the homopause (80-90 km altitude) is the point at which the molecular and eddy diffusion coefficients are equal or, in other words, the critical level below which an atmosphere is well-mixed. The exobase ( 550 km) is the height at which the atmosphere becomes collisionless above that height the mean free path of the molecules exceeds the local scale height (RTIg). 

In this correlation the effect of channel entrance loss, wdiich is a stabilizing factor for the system, is not included. The amount of the heat transfer at OFI depends on pressure through saturation temperature, Tg t Since pressure drop characteristics are not required, the accuracy of the prediction does not depend on two phase correlations (subcooled void fi action, pressure drop, and heat transfer coefficient). All two phase effects are included in parameter, 4i , and flow instability is intimately related to pressure drop. The pressure drop depends on the local water quality, which follows firom the axial heat distribution. 

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