Post-processors

Input and output subroutines to read and echo print data, allocate and initiahze working arrays, and output the final results generally in a form that a post processor can use for graphical representations. 

I am particularly indebted to Dr. Howard Lambert of Lawrence Livermore Laboratory and FfA Associates for providing the PC computer codes FTAP (fault ti ee code), POSTER (post processor), IMPORT (importance calculation), MONTE (Monte Carlo error determinadoni, and supporting documentation and instructions. 

Probe - The graphical post-processor for viewing the results generated by PSpice. For those readers familiar with MicroSim Design Center, this tool is relatively unchanged as well. 

A major improvement in terms of usability has been the addition of a graphical waveform post processing and schematic capture tools. Waveform post processors greatly facilitate computation and documentation of simulation results. Schematic capture automates the SPICE netlist generation dramatically reducing the number of syntax errors. 

Schematic capture Text editor SPICE Simulator Graphical post processor...

Duplicating the results from three simulators and measured data on one grphics post processor plot can be tricky. Each of the three simulators is capable of writing output data directly to a text file. To send PSpice... 

P 28] A 3-D solid model of the cross-shaped micro mixer is meshed to a sufficiently fine scale with brick elements of 2 pm for the simulations [71]. Simulation results were intended at very short time scales, e.g. in intervals of 50 ps, to verify the mixing patterns at the initial state after application of pressure. The numerical values of the mass fraction are taken to give quantitative measures of the mixing efficiency. The pre-processor fluidics solver and post-processor of ConventorWare were used for the simulations. The software FLUENT 5 was used for verification of these results, since the former software is so far not a widely established tool for fluid dynamic simulation. 

Ab initio (Hartree-Fock, Moller-Plesset, direct HF), semiempirical (MNDO, AMI, PM3), and molecular mechanics. Graphical front-end and post processor of the output. Cray, Convex, DEC, HP, IBM, and Silicon Graphics versions. 

A two-step global mechanism has been derived by de Soete [198] for the description of NO and N2 generation from fuel nitrogen. Parameters of the model were fitted to concentration profiles in flames. This model is widely used in post-processor packages of commercial CFD codes, although it works poorly under fuel-rich conditions. 

One major topic of the work is an extension of the CFD code with a post-processor for the fuel nitrogen to NOx conversion, A reduced kinetic scheme has been obtained which describes quite well the combustion emission behaviour with respect to NOx formation. Figure 9 shows a comparison between experimentally observed NH conversion to NO and modeling with this modified post processor. The agreement is reasonably good for experiments at 0.5 and 0.7 Mpa. Significant deviation between model and experiment is seen for an experiment at 0.4 MPa. This is attributed to a measurement error at that pressure, A recommendation is to perform more experiments at this or lower pressure. 

The performance of the gas turbine combustor in the Delft PDU with respect to main combustion product formation and fuel NO, was quite well predicted by FLUENT CFD modelling with a modified post-processor, although validation at pressures lower than 0.5 MPa is recommended. 

Although in many commercially available CFD codes, some capabilities of pre-and post-processors are bundled up with the solver, it will be useful to discuss the CFD tools by classifying them in the stated three categories. It is important to mention here that it is more useful to compare CFD codes based on underlying technological issues rather than based on their features . The main technological issues in pre-processors, solvers and post-processors are listed in Table 8.2, and are discussed in the following sub-sections. 

General Purpose CFD Codes FLUENT Pre-processors preBFC, GAMBIT, Tgrid Main codes Fluent4.5, FluentS, FIDAP, Rampant, Nekton, MixSim Post-processors in-built in above codes, Flpost www.fluent.com... 

AEA Technology Pre-processors CFX-Build Main codes CFX4, CFX5, CFX-ProMixus Post-processors CFX-Visualize www.aeat.com/cfx... 

CHAM Main code PHOENICS Post-processor PHOTON www.cham.co.uk... 

STAR-CD Pre- and post processor PROSTAR Main code STAR-CD... 

AVL Pre-processor FAME Main codes FIRE, SWIFT Post-processor in-built in above codes www.avl.com... 

CFDRC Pre-processor CFD-GEOM Main code CFD-ACE6, CFD-ACE (U) Post-processors CFD-VIEW www.cfdrc.com... 

TABLE 8.2 Key Issues for Evaluating CFD Pre-processors, Solvers and Post-processors ... 

Data storage/Exporting data to different post-processors... 

Numerical solutions of model equations generate large sets of numbers. Appropriate post-processing tools are essential to analyze and to interpret these simulation results. Many commercial CFD codes provide in-built post-processing facilities or allow results to be exported to other post-processing packages. The key issues in evaluating CFD post-processors are briefly summarized in Table 8.2. 

For quantitative validation of simulation results, it is often necessary to compare predicted profiles (of velocity or other variable of interest) with experimental data X-Y plotting facilities are useful for this purpose. Most post-processors allow the user to import tabulated data for comparison with simulation results. Facilities to calculate the usual global quantities of interest to reactor engineers, such as overall pressure drop, dispersed phase volume fraction, heat or mass transfer rates and so on, are necessary to address reactor engineering concerns. Most codes allow use of user-defined routines to evaluate different quantities of interest, which may then be displayed using the standard tools discussed above. 

In a first stage, three FUMAPEX modules for NWP model urbanisation (Figure 9.5) were developed for further testing and implementation into NWP models or their post-processors. It included the following modules ... 

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