Digital simulation program

Elliott s digital simulation program (EDSCAN) was developed to assist eustomers in designing reliable and eeonomie FCC systems. The program is used for analyzing any type of Elliott equipment, assoeiated... 

Full details of the ISlM digital simulation programming language can be found in the appendix, and by reference to the ISIM programs associated with the simulation examples of Chapter 5. 

Digital data can also be manipulated by spreadsheet programs and can be imported into digital simulation programs for comparison to theoretical curves. 

Gosser DK, Rieger PH (1988) Treatment of homogeneous kinetics in electrochemical digital simulation programs. Anal Chem 60 1159-1167... 

P. Baer and J. Frankie, Simulation of Interior Ballistic Peformance of Guns by Digital Computer Program, Rpt. 1183, BRL, Aberdeen, Md., 1962. 

Margolis, S. G., and J. A. Redfield, 1965, FLASH A Program for Digital Simulation of the Loss of Coolant Accident, WAPD-TM-534, Bettis Atomic Power Lab., Pittsburgh, PA. (6)... 

D7. Distefano, G. P., A Digital Computer Program for the Simulation of Gas Pipeline Network Dynamics. PIPETRAN, Version IV, Am. Gas Assoc., New York, 1970. 

Jfinr.- The easiest way to handle de time in a digital simulation is to set up an array for the variable to be delayed. At each point in time you use the variable at the bottom of the array as the delayed variable. Then each value is moved down one position in the array and the current undelayed value is stuffed into the top of the array. For fixed step sizes and fixed deodtimes, this is easy to program. For variable step sizes and variable deadtimes, the programming is more complex. 

Many advances in digital simulation have taken place since the publication of the first edition. Some of these advances have occurred in hardware through the development of the personal computer. Others have taken place by the development of commercial software that will perform specific simulations or will create a computer environment (e.g., a spreadsheet) that will allow one to do simulations without having to write a computer program. Finally, there have been theoretical advances where newer implicit algorithms are used to solve the necessary partial differential equations more efficiently than is possible using the more intuitive explicit methods described herein. 

Figure 20.4 Typical concentration profiles obtained using digital simulation. The conditions are identical to those employed in the sample program where the electrode reaction is A ne B. The lines represent the results of the simulation while the points show the exact solution obtained using partial differential equations. For a, b, and c the values of t/tf employed were 0.40, 0.80, and 1.00, respectively.

This work was supported primarily by the MRSEC Program of the National Science Foundation under Award Number DMR-0212302. A supercomputing resource grant from the University of Minnesota Supercomputing Institute for Digital Simulation and Advanced Computation is gratefully acknowledged. 

The Feldberg approach to digital simulation [229] uses a somewhat different method of discretisation, and the method is alive and well it is, for example, the basis for the commercial program DigiSim [482], It begins with Fick s first diffusion equation, using fluxes between boxes or finite volumes, rather than concentrations at points in the discretisation process (see below). 

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