I will discuss dispersion phenomena in high viscosity immiscible fluid systems and application of static mixers as dispersion devices in such systems in the following four steps: (iv) Application of (i) -(iii) to interpretation and prediction of dispersion performance at high viscosity in static mixers, at both low and high viscosity ratios.The information presented here is based on studies in model fluid systems of two phase liquid of high viscosity under creeping flow conditions, i. e., where the continuous phase viscosity was from 50 to 3000 poise, and very nearly Newtonian at the shears involved, the particle Reynolds number was in the range from 10 -2 to 10 -6, the interfacial tension varied from a fraction of a dyne to 25 dynes/cm, and the dispersed phase to continuous phase viscosity ratio varied from 10 -6 to 950.

The performance of nine typical filter media of previously determined pore structure has been determined by the filtration of very dilute suspensions containing spherical particles of known size distribution. The mechanisms of filtration prior to the formation of a macroscopic cake are considered, and the applicability of various filtration laws proposed by Hermans and Bred6e to describe these regions of filtration are examined. Regions of "standard-blocking" filtration are found to occur with each of the filter media examined. The clogging values for the various media over the region of standard blocking are shown to be related quantitatively to the modal value of interfiber pore radius of the media, as measured by the mercury-intrusion method.

The internal structure of various types of filter media and the nature of fluid flow through them are examined. Methods of characterizing the internal pore structure of filter media are reviewed, and the permeability, bubblepressure, and mercury-intrusion methods are applied to ten typical media, with resulting values of average and maximum pore radius and poresize distribution being reported. These data on internal pore structure are related to the construction variables characteristic of the media examined, in particular the effect of yarn construction, yarn twist, fabric weave, and fabric finish on textiletype filter media.The filter medium is an essential and very critical component of every filtration step and can make or break it from either an economic or a performance standpoint. Commercial filter media have been developed through the trial of hundreds of textile fabrics and other porous materials. Most of these were originally intended for other purposes, but through experience some five hundred or more have been found useful for filtering liquids. New filter media continue to evolve by this means. Few engineering criteria exist for the selection of existing filter media or for the design and construction of new media for efficicnt performance in the various types of filtration service. This lack of a quantitative basis for both the design and selection of filter media is largely responsible for the wide and continually changing variety of filter media in general use.Experimental procedures for correlating physical characteristics, internal structure, and performance are needed before any major improvement in this situation can be expected. A means of quantitatively relating these factors should result eventually in the design of the best filter media for particular types of service. The immediate objectives of the work reported in Parts I and I1 of this paper were the development and application of techniques for evaluating porc structure and functional performance of filter media and the correlation of these factors with each other and with other measured properties of filter media.

Discharge coefficients were determined in a standard 1-in. pipe for thick-plate and knife-edge orifices of 1/32-in. to 3/4-in. diam, and for critical (sonic) flow nozzles of 1/32-in. to 1/4-in. diam. With properly constructed knife-edge orifices the discharge coefficients were established within ±0.5 per cent for all sizes, but, with small orifices of 1/4 to 1-hole-diam thickness, the discharge coefficients were not reproducible. Thick-plate orifices (1-hole-diam thick) were found to be as good or better than nozzles in constancy of discharge coefficients when used under critical-flow conditions.

In the past year, Constellation Power Source Generation (CPSG) has commissioned (or is commissioning) four new combined cycle and simple cycle gas turbine plants. Each of these plants involved different equipment, vendors and architect engineers. Acceptance testing was done for these plants in accordance with ASME PTCs 46 and 22 with support from Fossil Consulting Services, Inc. (FCS). The Performance Test Codes provided the framework for the testing done, but considerable work was required to apply the codes in accordance with relevant contracts. Problems in acceptance testing can result in costly delay and retesting. This paper describes the lessons learned in resolving issues and problems that can help others in planning for and executing similar tests. These lessons learned can also help in writing effective contracts between owners, vendors and architect engineers.