Designs correlated

An extensive treaunent of gas-liquid flows encountered in industry applications, along with numerous design correlations can be found in Volume 3 of the Encyclopedia of Fluid Mechanics - Gas-Liquid Flows (N. P. Cheremisinoff, editor. Gulf Publishing Co, Houston, TX, 1986). Further discussions in this volume can be found in Chapter 4 with regard to flow regimes typically encountered in bubble columns and similar devices. 

Static mixers are typically less effective in turbulent flow than an open tube when the comparison is made on the basis of constant pressure drop or capital cost. Whether laminar or turbulent, design correlations are generally lacking or else are vendor-proprietary and are rarely been subject to peer review. 

Prototype geometries are used in the tests for developing design correlations for the equipment, while simple geometries are used in the tests for understanding the basic mechanisms of CHF. 

For convenience of outside design reviewers, GE has also developed an approximation of its proprietary core design correlation, called the CISE-GE correlation (GE Report, 1975), which follows the format of the CISE-1 correlation but... 

As discussed in other chapters of this book, two-phase flows of gas and particles occur with different flow regimes. The mechanisms for heat transfer and the resulting heat transfer coefficients are strongly affected by the different flow characteristics, resulting in different design correlations and predictive models for each flow regime. This chapter will deal with the two most often encountered flow regimes ... 

Quantitative design correlations to meet these requirements are available in the literature [1-3]. 

In the past, mass production of mathematical models and column design correlations was hindered by the extensive calculations involved. With the event of high-speed and personal computers, this bottleneck has been eliminated. Flood gates have opened, and new mathematical models are pouring into the published literature at a record pace, Further growth in mathematical model production appears to be restricted only by the availability of persons willing to punch buttons on computer keyboards,... 

What hope has the designer who sits at the other end of the rainbow and attempts to make use of the mathematical models and design correlations ... 

Of course, computers can also be used for formulation data storage and acquisition. There are four papers in this section which deal with these topics. Papers by Botts and Mookerjee describe the theory and programs associated with experimental design, correlation and optimization. Both authors work through actual problems. 

The "master correlation" for Tg (Equation 6.3) consistently overestimates the Tg s of the polyphthalimides completely built from C, N, O, S and H atoms. (See Torlon and Ullem in Figure 2.4, and the polymers in figures 6.6 and 6.7.) A specialized "designer correlation" will now be developed for the Tg s of this important class of polymers. Fourteen of the polymers in... 

Figure 17.1. Designer correlation for the glass transition temperatures of 14 polyphthalimides containing only C, N, O, S and H atoms.

A designer correlation was developed by Mumby [3] for the glass transition temperatures of the 21 polyesters included in Table 6.2. In developing this correlation, which is given by Equation 17.2, the solubility parameter was consistently calculated by the method described in... 

Figure 17.2. Designer correlation for the glass transition temperatures of 21 polyesters.

Figure 17.3. Designer correlation for Fedors-type cohesive energies of 25 hydrocarbon polymers.

The polymers shown in Figure 17.4 each contain a structural unit whose contribution to ECoh(Fed°rs) is not listed in the group contribution tables [4,5], so that Ecoh(Fedors) cannot be calculated for these polymers by using group contributions. Calculations of E for these seven polymers by using the new correlations (equations 5.10-5.12 for the general-purpose correlation, and Equation 17.3 for the designer correlation) are summarized in Table 17.4. 

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