Resonance, hydraulic

For the pressure studies, two phase" compact ion behavior is observed with an inflection point between 7 and 11 atms. For the aqueous solution studies, the hydraulic permeability K and the g-ratio are hardly effected by solute type (within experimental error). The solute diffusive permeability however, varies with solute type in good qualitative agreement with free energy parameters, infrared overtone shifts, and spin echo and continuous wave nuclear magnetic resonance spectroscopy results from the literature. 

Meyer was known for his researeh in asymptotic analysis, partial differential equations, plasma physics, water waves, meteorology, and in gas dynamics. In the latter field he explored supercritical nozzle flows. In water waves theory, the fundamental hydraulics were studied in collaboration with Joseph B. Keller (1923-), including wave refraction and resonance, extending short wave asymptotics to obtain notable advances in the spatial theory of the classical water waves with applications to both coastal and shelf oceanography. He was a member of the Australian Academy of Sciences. Meyer was an individualist who marched to no one s drum but his own. 

The excitation of this very complex spring-mass system was now such that resonances with the flow were possible (Teng-yang et al., 2000). Most of the lower frequencies could have been excitable by the very broad range of flow velocities present, particularly near the two hydraulic jumps (EJMA, 1993). Additionally, the jetting at the base of the weir outfall could possibly result in axial resonance of the bellows. Coherent turbulence may also have been able to excite the higher modes. 

FIG 3.5. The period of hydraulic resonance varies with the distance between the bounded surfaces. 

The vessel is in a high state of turbulence and naturally exhibits a certain hydraulic resonance, which was described in Chap. 3. But liquid level is affected thermodynamically as well. For example, the sudden introduction of feedwater below its boiling point can momentarily reduce the heat content of the vapor liquid mixture in the tubes, causing bubbles to collapse, and reducing the apparent liquid level. Thus the response of the level-control loop has a tendency to start in the wrong direction. 

This property is called phase shifting and is similar to dead time in that it produces phase lag without attenuation. The result is that the period of the liquid-level loop is ordinarily several minutes, although its natural hydraulic resonance may be only a few seconds long. 

The frequency response of the closed loop transfer function of thermal-hydraulic stability for the average power channel of the Super LWR at 100% power operation with different mesh sizes (assuming an orifice pressure drop coefficient of 10) is shown in Figs. 5.28 and 5.29. A resonant peak is observed at the frequency of about 2.5 rad/s due to the flow feedback effect. A similar resonant peak is observed at the frequency of about 4 rad/s for the 100% maximum power channel as shown in Figs. 5.30 and 5.31. These resonant frequencies are consistent with the corresponding coolant transit time (about 1.6 s for the average power channel and about 1.0 s for the maximum power one). 

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