Comparison of simulation and experiment

R. Radhakrishnan, K.E. Gubbins, A. Watanabe and K. Kaneko, Freezing of Simple Fluids in Microporous Activated Caibon Fibers Comparison of Simulation and Experiment, J. Chem. Phys. 111 (1999) pp. 9058-9067... 

G. Garberoglio, A.I. Skoulidas, and J.K. Johnson, Adsorption of Gases in Metal Organic Materials Comparison of Simulations and Experiments. J. Phys. Chem. B, 2005, 109, 13094-13103. 

Giordano, R.M., Salter, S.J., 1984. Comparison of simulation and experiments for compositionally well-defined corefloods. Paper SPE 12697 presented at the 4th Joint SPE/DOE Symposium on Enhanced Oil Recovery, Tulsa, 15-18 April. 

TABLE 2. Comparison of simulation and experiments for local Nusselt numbers in micro-channel (x = L/2 and x = L). 

Vlachos DG, Bui PA Catalytic ignition and extinction of hydrogen comparison of simulations and experiments, Surf Sd 364 1625—1630, 1996. 

Figure 15 Comparison of theory and experiment for the fractionation of oligoade-nylates on ion exchange materials, (a) Simulated chromatogram, (b) Observed chromatogram. An example of how theory is being used to attempt to optimize performance of ion exchange materials. The curve in (a) shows the nonlinear gradient development with a convex curvature. (Reproduced with permission of Elsevier Science from Baba, Y., Fukuda, M., and Yoza, N., J. Chromatogr., 458, 385, 1988.)...

The methodology discussed previously can be applied to the study of colloidal suspensions where a number of different molecular forces and hydrodynamic effects come into play to determine the dynamics. As an illustration, we briefly describe one example of an MPC simulation of a colloidal suspension of claylike particles where comparisons between simulation and experiment have been made [42, 60]. Experiments were carried out on a suspension of AI2O3 particles. For this system electrostatic repulsive and van der Waals attractive forces are important, as are lubrication and contact forces. All of these forces were included in the simulations. A mapping of the MPC simulation parameters onto the space and time scales of the real system is given in Hecht et al. [42], The calculations were carried out with an imposed shear field. 

The comparison of simulation and measurement data of an uncoated membrane is shown in Fig. 4.7. The temperature curves, T to T4, were measured with the on-membrane temperature sensors. The graphs of the simulated temperatures are denoted Si to S4. The temperature discrepancy between simulation and experiment was less than 5% for all sensors. The general shape of the temperature distribution was correctly modeled within measurement accuracy. It has to be noted that no additional fitting parameters were used for these simulations. 

Evidently, more work has to be done for a comprehensive comparison of theory and experiment. Theory and simulations reveal clearly that the PB-cell model should be a poor approximation for divalent counterions and breaks down totally for trivalent counterions [29]. A comprehensive experimental test of these very important conclusions is still missing. 

The constituent properties from Table 1.3 can, in turn, be used to simulate the stress-strain curves (Fig. 1.31). The agreement with measurements affirms the simulation capability whenever the constituent properties have been obtained from completely independent tests (Table 1.1). This has been done for the SiC/CAS material, but not yet for SiC/SiC. While the limited comparison between simulation and experiment is encouraging, an unresolved problem concerns the predictability of the saturation stress, crs. In most cases, ab initio determination cannot be expected, because the flaw parameters for the matrix (processing sensitive. Reliance must therefore be placed on experimental measurements, which are rationalized, post facto. Further research is needed to establish whether formalisms can be generated from the theoretical results which provide useful bounds on as. A related issue concerns the necessity for matrix crack density information. Again, additional insight is needed to establish meaningful bounds. Meanwhile, experimental methods that provide crack density information in an... 

In spite of the previous comment, comparison between simulations and experiments (not presented here ) is fully convincing as far as the purpose of such a model is to allow predicting the burst pressure of a vessel when the thickness of the liner and the stacking sequence are known. It means for every burst pressure and consequently for any use pressure, one or several stacking sequences may be found to ensure the strength of the structure. 

Fig. 13. Comparison of simulated and experimentally measured silicon hydride composition of a-Si H film surfaces at (a) a low temperature (500 K) and (b) a high temperature (experiment at 640 K, simulation at 773 K).

Lipari, G., Szabo, A., Levy, R.M. Protein dynamics and NMR relaxation Comparison of simulations with experiment. Nature 1982, 300,197-8. 

It is, however, most Important to make the comparisons of simulator and In-vlvo wear rates with findings from laboratory wear machine experiments in which the environment and counterface topography are adequately represented. 

Contrary to the results for labile Ni, the gradients of relative concentrations of dissolved Ni obtained with the model including exudation (Model 3) matched water-extractable Ni data better (Fig. 2b). The curves produced by the other models were more discrepant. Water extracts may not represent real soil solutions and freezing of soil samples might have introduced additional artifacts. However, gradients of Ni concentration in soil solution were not available. Water-extractable Ni data in Fig. 2b are presented for orientation but caimot be used for proper model corroboration. All simulated curves were opposite to the trend implied by measured water-extractable Ni. Accumulation of solutes near the root is known for excluders or for situations where convective flow toward the root exceeds plant demand. This was not the case in our experimental system. In future experiments, the use of microsuction cups will enable comparison of simulated and measured dissolved Ni (Wenzel et al., 2001). 

Nonthermally activated reactions in condensed phases, such as photodissociation processes, have been a popular area of study via computer simulation for several reasons. In part these reasons are historical The first computer simulations of reactions in liquids were performed on Ij photodissociation in carbon tetrachloride and in dense rare gases. Almost concurrently with these early simulations, the first experiments on this process with picosecond resolution were being performed.Photodissociation makes for easy comparison between simulation and experiment, because the experimental zero of time, namely the excitation to an upper electronic state, can be easily duplicated in the simulation. As we shall sketch out in the first part of this section, the use of molecular dynamics in helping to understand and explain the I2... 

THE COMPATIBILIZATION OF POLYMER BLENDS WITH LINEAR COPOLYMERS COMPARISON BETWEEN SIMULATION AND EXPERIMENT... 

Experimental test of model involves comparison of theory and experiment with respect to numerical simulation. A falsifier, as postulated by Karl Popper, would be needed for a still more rigorous test. Even if it is not possible, the exercise in modelling does give an insight in to the physics of the phenomena. 

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