Helium data

In power plant practice, the practical source of oxygen is primarily air. which includes, along with the oxygen, a mixture of nitrogen, water vapor, and small amounts of inert gases, such as argon, neon, and helium. Data on the composition of air are given in Table 3. 

The experimental helium data are shown in Figure 5.16, along with the theoretical results of Ihra et al. (1997), and good accord between the two is found. Thus, Ihra et al. (1997) deduced that, for most of the energy range investigated, the experiment can be fitted by a threshold law of the form of equation (5.10). This threshold law was derived by... 

Calibration of a CFD model, of the accident scenario, using helium data... 

A helium data verified CFD computer model can accurately predict the spatial and temporal distribution of hydrogen released in a hydrogen escape. 

Fig. 14.4 Helium concentration (corrected for gas losses) as a function of distance from the recharge area along two transects through the Great Artesian Basin (following Mazor and Bosch, 1992a). The good correlation provides a positive check on the validity of the corrected helium data, as the deeper inland groundwater must have been trapped earlier.

The other gases used were examined in the same way as helium. In all cases the flow exceeded the Knudsen flow as predicted from the helium data. Figure 8 gives typical data the flow in excess of the calculated Knudsen flow is attributed to surface diffusion of the adsorbed molecules. 

Temp., Total Flow, Knudsen Flow, Calcd. from Helium Data, Surface Flow,... 

From your helium data and the known valnes of Fj and F2, calculate F3 from Eq. (7). If the temperature at the gas burette has been fairly constant thronghont the experiment, use the average value as Tg in Eq. (10) and calculate values of V% when F = Fj + F2 + F3 and when Vg = V2+ F3. These values can then be used in all further calculations. If Tg has varied by more than 0.5°C, appropriate changes in shonld be made where necessaiy. Now use Eq. (9) to calculate s-... 

Fig. 10-4. Uncorrected helium data from soil-gas (probe) survey at the Red Desert research site (A) collected during summer and (B) collected during winter (from Pogorski and Quirt, 1979).

Rice et al. [36] have used Eq. (61) to analyse their calculations of Py for HCHO and CH3F. Bishop and Pipin [11] have used Eqs. (62) and (63) to express their low-frequency helium data (fim < 0.02 Eh). They found the dispersion coefficients which are given in Table 11. It is apparent that A is indeed the same for all processes, A is nearly the same for dc-K and dc-SHG and that B follows quite precisely the ratios given above if k = 0.966. 

Multiple sets of Burnett data were obtained for each isotherm—three sets for ethylene and two sets for helium. Each set consisted of data from a series of four consecutive expansions from the highest to the lowest pressure compatible with our optimum accuracy and precision. The initial pressure for each set was selected so as to intersperse the data from all of the sets over the entire pressure range of interest, 0.3 MPa to 3.7 MPa. Consistent with the extent of the nonideal behavior of the gas, the density-series generalized equation was applied to the ethylene data and the pressure-series generalized equation was applied to the helium data. The parameters in the resulting overdetermined sets of equations then were evaluated using the least-squares constraint. 

The highest power of the series terms chosen to define each isotherm reflected the extent of the nonideality. For the ethylene isotherms, a cubic series was used for temperatures from 0° to 25°C and a quadratic series was used for temperatures from 75° to 175°C. At 50°C, a quadratic series as well as a cubic series were used. For the helium isotherms, a quadratic series was used with the virial coefficient of the quadratic term treated as a constant obtained from published values rather than as a parameter. The other parameters were evaluated more accurately with the quadratic coefficient treated as a constant rather than as a parameter since the contribution of this term was so small for our range of pressures. The term functioned only as a virial remainder. In the helium data analyses, the parameters were common to all of the data. For the ethylene data analyses, only the virial coefficient parameters were common to all of the data an initial density parameter was required for each sequence... 

For Case 1, N is a constant determined from Burnett helium data for Case 2, N is a single parameter and for Case 3, N is a parameter for each designated set (sequence of expansions). 

Figure 1.10 presents the similar transformation, to Figure 1.9 of the helium data, for the numerical rR(r) data for the lithium Is and 2s orbitals. Construct the spreadsheet as follows. 

Helium p. ] Although considerable amounts of new data have been published for values below 20°K, very few new measurements have been reported in the temperature range 20° to 300°K in the past 35 years. All of the published helium data from 20° to 100°K are for pressures below 100 atm, while all data below 20°K are limited to 140 atm. The many uses of helium over the entire temperature spectrum, and extending to very high pressures indicate a growing need for additional measurements. 

The results of applying this method to the present 10 Fe-Ni-base alloys are given in Table VII, where they are compared with those of direct measurement. The percentage differences between the calculated and measured specific heats are the bracketed quantities. Table VII shows that room-temperature specific heats calculated from liquid helium data are reliable to within 4%. Universal plots of C, vs. T/do (e.g., ReL 8) show that specific heat varies most rapidly with temperature for values of T/do between about 0.1 and 0.3, i.e., for a temperature range... 

G-9.1 Commodity Specification for Helium. Covers specification requirements for commercially produced grades of helium. Data regarding quality verification systems, sampling, analytical procedures, supplemental specifications, tables, and charts are included. (12 pages)... 

The actual interface temperature within the screen pores may be different from the measured liquid screen side temperature due to enhanced heating (vapor case) or cooling (helium case) at cryogenic temperatures. In Equation (3.16), surface tension is evaluated based on the liquid screen side temperature, but the helium data in Figure 5.10 imply that the interfacial temperature is cooler than the liquid screen side. In other words, unlike storable bubble point data, for cryogenic bubble points, it matters which pressurant gas is in contact with the screen. 

For temperature differences within the liquid, the trends in Figure 7.12b mirror Figure 7.12a with subtle variations. Most of the helium data indicate that the liquid at the screen was colder than the bulk liquid at breakthrough while the nitrogen data shows... 

Below 200 atm, there is little variation in the value of /ajt for helium. (Also note that the helium data use Kelvin temperatures.)... 

---