Fluid recommended model parameter

Hq( is also influenced by gas velocity (slightly) particle size distribution (e.g. fines (particles with dp < 44y) percentage), temperature and pressure. Recommended values have been given elsewhere ( ), but more data are needed. Models of level I are flexible and ceui cope with the complex phenomena occuring in the fluid bed. The parameters should be measured separately which is costly emd time consuming but rell2tble (This was called "Cautious empirsm" by Davidson (55)). 

As a general rule of thumb, caution and reserve is recommended when applying empirical correlations to new processes. They may predict reliable data in many cases while, in others, they fail completely. In recent years, new hydrodynamic models for BCR have been developed [[13 - 16. Summaries can be found in papers by Shah and Deckwer [17J and Deckwer and Schumpe [18[. As a main result, these models predict liquid mixing and circulation flow rates and confirm dependencies upon various parameters found empirically. It is understood that the hydrodynamic models refer to the bulk fluid flow and are therefore not able to predict typical interfacial parameters and micro phenomena within the bulk liquid phase like micromixing and se-... 

At the present state these correlations together with Eq. 23 for the prediction of the apparent heat conductivity amd Eq. 6, 7 for the particle-to-fluid heat transfer may be recommended for application in tubular reactor design. These correlations give fairly reliable parameters for either homogeneous or heterogeneous one or two dimensional models for the mathematical simulation of packed bed reactors. 

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