Numerical modelling measurements comparison

Eltgroth, M. W., and Hobbs, P. V. (1979) Evolution of particles in the plumes of coal-fired power plants—II. A numerical model and comparisons with field measurements, Atmos. Environ., 13, 953-976. 

This paper is structured as follows in section 2, we recall the statement of the forward problem. We remind the numerical model which relates the contrast function with the observed data. Then, we compare the measurements performed with the experimental probe with predictive data which come from the model. This comparison is used, firstly, to validate the forward problem. In section 4, the solution of the associated inverse problem is described through a Bayesian approach. We derive, in particular, an appropriate criteria which must be optimized in order to reconstruct simulated flaws. Some results of flaw reconstructions from simulated data are presented. These results confirm the capability of the inversion method. The section 5 ends with giving some tasks we have already thought of. 

Such an experimental characterization is a necessary step to carry out a detailed comparison of emission properties as measured experimentally with the corresponding quantities as calculated by numerical models capable of describing transport and energy deposition of fast electrons in matter and consequent emission of characteristic X-ray emission. A possible modeling approach of fast electron transport experiments is given here, where the above results on Ka imaging were interpreted using the hybrid code PETRA [53] to... 

The numerical model is implemented for the three current collector configurations previously mentioned. Since the model uses semi-empirical parameters, this is first calibrated and then validated, through a comparison with experimental data. For collecting the current, a silver wire is wrapped around the cathode, while a nickel spring is placed in contact with the anode (case 3 previously defined). The tests are performed using pure hydrogen at a constant flow rate. Voltage is varied by the use of a load bank, and the relative current is measured. The temperature of 800°C is... 

Sahagian DL, Anderson AT, Ward B (1989) Bubble coalescence in basalt flows Comparison of a numerical model with natural examples. J Vole Geotherm Res 52 49-56 Sahagian DL, Maus JE 1994 Basalt vesicularity as a measure of atmospheric pressure and paleoelevation. Nature 372 449-451... 

Field data are of great importance both in bioinformatics and geoinformatics software applications not only for making estimations, comparisons, and predictions, but also for calibrating held data in mathematical numerical models in order to develop useful simulation numerical spatial tools, which ultimately help take the right measures for a given topography on time. 

A quantitative comparison between the numerical model and experimental data can be made using those measurements of bubble volume and bubble rise velocity. The calculated values of bubble volume and bubble rise velocity for both ambient and high pressure conditions and also for some complex geometries such as the Westinghouse Cold Flow 30 cm diameter semi-circular model, are shown as large symbols in Figure 2. The specific geometries and flow conditions for the calculations are listed in Table I. 

In the following, the measurement techniques and the fundamentals of the numerical modelling studies as well as their application on small scale domestic wood stoves will be described. Furthermore, relevant experimental results and information obtained by the numerical modelling studies as well as a detailed comparison of measured and computed data will be shown by means of an example for a commercially available tile stove heating insert. 

A further comparison of calculated and measured CO-concentrations and temperatures, given in Figure IS. show also a good correspondence. Differences between measured and calculated data, especially for the temperatures can be put down to the already mentioned fact of an incorrect predicted size of the recirculation zone in the upper left part of the burnout zone by the numerical model. However, the experimental determination of gas concentrations as well as of gas and wall temperatures is often in involved with uncertainties and measuring errors, especially under the prevailing instationary conditions within a domestic wood heater. 

The comparison between measurements and numerical results of fig. 10 shows some disparities. Three zones can be distinguished. In zone 1, close to the sparger at the plume bottom, the diameter of the bubbles is gauged at less than 1 mm. Along the plume, the diameter of the rising bubbles increases, probably by coalescence. Since all the forces acting on the bubbles depend on their diameter, the numerical model overestimates the size of the bubbles in the bottom of the plume. In the second zone, computed and measured velocities are practically identical. It is thought that the bubble diameters have their nominal value in this zone. 

Figure 10 Comparison between numerical model and measurements for gas...

Fig. 5. Comparison of power law relationships between capillary pressure (psi) and permeability derived from the numerical model and as fitted to laboratory measurements of samples from a North Sea field. (The numerical model results represent a narrow pore size distribution at both 10 and 25% saturation). Squares repre.sent data, diamonds represent the model results.

In addition to the discrete measurements it is anticipated that the results from the acoustic emission and ultrasonic arrays will play a major role in facilitating the comparison between the numerical model predictions and the measured response as these tools will capture the 3D temporal and spatial response of the pillar to the increasing temperature. 

Azole compounds have been tested in the mouse model of Chagas disease in numerous laboratories. Direct comparisons between studies can be difficult because of the use of diffident protocols, diffierent strains of T. cruzi, and different outcome measurements. A pardculady problematic challenge with all of these studies is the test of cure of the animals. The tests include hemoculture, xenodiagnosis, serology, PCR, tissue analysis, and combinations of these. The reader is referred to the original papers for details. 

The models have been calibrated with field observations and the results are given here. Tide and current data from three temporary observation stations are used to verified and validate the present model. By comparison, the numerical calculation results are in good agreement with the measured data (see Fig. 4 and Fig. 5). 

Tence, M., Chevalier, J. P. and Jullien, R. (1986). On the measurement of the fractal dimension of aggregated particles hy electron-microscopy - experimental-method, corrections and comparison with numerical-models. J. Phys., 41, 1989-1998. 

The last equation demonstrates that the starting point for the solution of the problem is the calculation of ci(double layer (this makes low-frequency dielectric dispersion [LFDD] measurements a most valuable electrokinetic technique). Probably, the first theoretical treatment is the one due to Schwarz [61], who considered only surface diffusion of counterions (it is the so-called surface diffusion model). In fact, the model is inconsistent with any explanation of dielectric dispersion based on double-layer polarization. The generalization of the theory of diffuse atmosphere polarization to the case of alternating external fields and its application to the explanation of LFDD were first achieved by Dukhin and Shilov [20]. A full numerical approach to the LFDD in suspensions is due to DeLacey and White [60], and comparison with this numerical model allowed to show that the thin double-layer approximations [20,62,63] worked reasonably well in a wider than expected range of values of both and ku [64]. Figure 3.12 is an example of the calculation of As. From this it will be clear that (i) at low frequencies As can be very high and (ii) the relaxation of the dielectric constant takes place in the few-kHz frequency range, in accordance with Equations (3.56) and (3.57). 

The results of these experimental measurements of the liner trajectory were compared with a numerical model for the implosion obtained from a 1-D, Lagrangian, hydrodynamic code containing a detailed treatment of the equation-of-state of the liner material. Figure 17 shows such a comparison for a 1.4 MJ shot. The point labeled as "abrupt current change" marks the discontinuity in the slope of the current trace caused by the sudden ending of the IL contribution to the voltage when the liner hits the axis. The... 

Fuel-rich H2/air hetero-Zhomogeneous combustion was less studied than its fuel-lean counterpart. Maestri et al. (2007, 2008) investigated fuel-rich H2Zair combustion on Rh-based catalysts at atmospheric pressure in a nearly isothermal annular reactor with channel gap of 2.1 mm. Fundamental homogeneous ignition studies were reported only recently (Schultze et al., 2013) in the Pt-coated reactor of Fig. 3.2, at pressures up to 5 bar, nonpreheated fuel-rich H2Zair mixtures, and surface temperatures 760 K< T < 1200 K. Fig. 3.10 provides comparisons between LIF-measured and -predicted OH distributions at two different pressures. Simulations were performed with the hetero-Zhomogeneous reactions schemes from Deutschmann et al. (2000) and Li et al. (2004). Raman measurements further attested a nearly transport-Umited conversion of the deficient O2 reactant, which was captured by the numerical model (Schultze et al.. 

Figure 26.4 shows comparisons among the Barrass, Er3mzlu, Huuska, ICORELS, Romisch, and Yoshimura formulas and the measured BAW laboratory values. The numerical values are from a numerical model described in Sec. 26.6. In general, the best formulas are the Yoshimura (Concept) and Er3mzlu (Detail) as they are slightly... 

Fig. 26.4. Comparison of BAW s experimental measurements, empirical formulas, and numerical model of bow squat for a Post-Panamax containership in an unrestricted channel (open water).

Figures 26.4-26.6 showed comparisons of the PIANC empirical formulas with the measured laboratory measurements. These figures also included comparisons with the numerical model predictions for each example. These examples included BAW s PPM containership in an unrestricted channel, FHR s tanker in restricted water, and Tothil s Canadian Laker in a canal. In general, the numerical model matched the measured values from the laboratory measurements very well. Details of the individual examples are given in the following sections.

The mesh contains 57,602 nodes, 255,447 tetrahedra, and 58,458 triangles. A general comparison between squat measurements, empirical formulas, and the numerical model was shown in Fig. 26.4. The numerical modeling match is very good, with a maximum error smaller than 0.12 m. 

The mesh contains 35,149 nodes, 158,022 tetrahedra, and 33,532 triangles. Figure 26.5 showed the comparisons. The numerical model had to rotate the hull (trim) around the center of gravity. The agreement with the measured values was reasonable. 

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