Pressures, equivalent

A useful simphfication of the total energy equation applies to a particular set of assumptions. These are a control volume with fixed solid boundaries, except for those producing shaft work, steady state conditions, and mass flow at a rate m through a single planar entrance and a single planar exit (Fig. 6-4), to whi(m the velocity vectors are perpendicular. As with Eq. (6-11), it is assumed that the stress vector tu is normal to the entrance and exit surfaces and may be approximated by the pressure p. The equivalent pressure, p + pgz, is assumed to be uniform across the entrance and exit. The average velocity at the entrance and exit surfaces is denoted by V. Subscripts 1 and 2 denote the entrance and exit, respectively. 

The Navier-Stokes equations are greatly simplified when it is noted that = = 0 and dv /dx = three components are written in terms of the equivalent pressure P ... 

As for any incompressible single-phase flow, the equivalent pressure P = p + pgz where g = acceleration of gravity z = elevation, may be used in place of p to account for gravitational effects in flows with vertical components. 

Table A.4 Head of water in feet and equivalent pressure in pounds per square inch ...

The disturbance caused by a noise depends on its intensity (equivalent pressure level L in dB(A)), its frequency spectrum (that is its energy distribution), and the acoustic characteristics of the medium in which the listener is kicated. 

Equivalent pressure The pressure corresponding to standard density,... 

SUVA 9000 (R-407C) HCFC-22 An equivalent pressure replacement for HCFC-22 with 0 ozone depletion potential for use in commercial and residential air conditioners and heat pumps. Suva 9000 provides the closest match to HCFC-22 performance in existing HCFC equipment design. 

The table shows the length of pipe with equivalent pressure loss in a given size and type of fitting. ... 

All five of the factors that control the actions of fluids can be expressed either as force or in terms of equivalent pressures or head. In either situation, the different factors are referred to in the same terms. 

Water is flowing in a horizontal pipe bend at a velocity of 10 ft/s. The radius of curvature of the inside of the bend is 4 in., and the pipe ID is 2 in. A mercury manometer is connected to taps located radically opposite each other on the inside and outside of the bend. Assuming that the water velocity is uniform over the pipe cross section, what would be the manometer reading in centimeters What would it be if the water velocity were 5 ft/s Convert the manometer reading to equivalent pressure difference in psi and Pa. 

Boiling and cavitation are intimately related. Volmer argued that the two types of rate equations, such as Eqs. (49) and (52), should merge or agree at some point. The equivalent pressure-sensitive groups, Bi and B2, are plotted2 in Fig. 17. The estimated form which Bi and B2... 

The value of the absorption coefficient is calculated for each pair of equivalent pressure and temperature characterising the layer. 

Figure 18 CO2 transients on 4nm Pd particles supported on MgO(l 00) as a function of sample temperature with an isotropic pressure of oxygen (5 x 10 8 Torr) and a pulsed molecular beam of CO (3.4 x 107 Torr equivalent pressure) (from Ref. [146]).

The micrographs of the different samples are represented on Fig. 21. D mean diameter, n cluster number density, T sample temperature, P02 oxygen pressure, /idjp/Vss amplitude of the dip divided by the steady state production rate of CO2 (see text). The equivalent pressure of the CO beam is 3.4 x 10-7 Torr (from Refs [88,145] and unpublished results). 

Figure 25a shows the steady state production rate of C02 calculated for various CO pressures. We recognize the typical volcano shape observed in the experiments. The temperature corresponding to the maximum rate is very close to the experimental values. Figure 25b displays the variation of the coverage of the adsorbed species as a function of temperature for a NO pressure of 5 x 10-8 Torr and the same equivalent pressure in the CO beam. The nitrogen coverage is not represented because it remains very low due to the small barrier for associative desorption of N2. At low temperature, the concentration... 

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