Liquid nitrogen bubble point pressure

FIGURE 5.16 Liquid Nitrogen Bubble Point Pressure Dependence on Pressurant Gas for (a) 325 x 2300, (b) 450 x 2750, and (c) 510 X 3600 Screens. The black line is the prediction curve based on the room temperature pore diameter. 

FIGURE 8.7 Heated Pressurant Gas Liquid Nitrogen Bubble Point Pressure as a Function of the Temperature Difference between Pressurant Gas and Liquid. 

Parametric Analysis of the Liquid Hydrogen and Nitrogen Bubble Point Pressure... 

FIGURE 7.10 Combined Liquid Temperature, Pressure, and Pressurant Gas Type Dependence on 325 x 2300 Liquid Methane Bubble Point Pressure using (a) Helium, (b) Nitrogen, and (c) Methane as Pressurants. Color indicates bubble point in units of [Pa],... 

HGURE 5.10 Bubble Point Pressure Dependence on Screen Mesh in (a) Liquid Hydrogen and (b) Liquid Nitrogen. Solid lines are computed from Equation (3.16) using pore diameters determined at room temperature. 

A %-in. connection is provided on the pump suction downstream of the block valve. It is attached permanently to a gas pressurizing source, such as fuel gas or nitrogen. Obviously, the connection has to be made to a source that can provide gas at pressures above the bubble point of the liquid being pumped. 

FIGURE 11.7 (a) Data and (b) Model Generated Bubble Point as a Function of the Liquid Temperature and Pressure at the LAD Screen for a 325 x 2300 Mesh in Liquid Nitrogen using Gaseous Helium as a Pressurant. The black line is the nitrogen saturation curve. Color indicates magnitude of the reseal point. 

Example 6.5. Determine the bubble-point and dew-point temperatures for a 50 mol % nitrogen-50 mol % oxygen mixture at a pressure of 0.506 MPa utilizing the equilibrium constants given in Table 6.2. Compare these results with those obtained assuming that the liquid is a perfect solution and the vapor behaves as an ideal gas. 

If the liquid is assumed to be a perfect solution, the bubble-point temperature can be obtained in the same manner as the preceding except that the equilibrium constants for the nitrogen and oxygen are obtained as ratios of the vapor pressure to the total pressure of the mixture, i.e., K P Ip. The bubble-point temperature can also be obtained by utilizing Raoult s law and recognizing that the sum of the partial pressures must equal the total pressure when the correct temperature is selected. Thus... 

Solution. By interpolation Table 6.3 indicates that the dew-point temperature for a 79 mol % nitrogen-21 mol % oxygen mixture under a pressure of 0.101 MPa is 81.7 K. Thus, condensation does occur. Since the bubble-point temperature for this same mixture at the same pressure is 78.9 K, a two-phase mixture will be present at 80 K. The composition of the liquid phase can be obtained with the use of Eq. (6.22) and the equilibrium constants for nitrogen and oxygen from Table 6.2. Thus... 

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