Meteorological design

This article is intended to provide a useful first understanding of flow phenomena and techniques and to provide an entry to more precise and detailed methods where these are required. Although the main concern is the proper design and operation of plant equipment, the importance of preservation of the environment is recognized. Thus data from the fields of meteorology and oceanography are occasionally needed by the technologist (see also Flowl asurel nt Fluidization). 

First order parameters affecting dispersion stem from meteorological conditions. These, as much as any other consideration, determine how a stack is to be designed for air pollution control purposes. Since the operant transport mechanisms are determined by the micro-meteorological conditions, any attempt to predict ground-level pollutant concentrations is dependent on a reasonable estimate of the convective and dispersive potential of the local air. The following are meteorological conditions which need to be determined ... 

This chapter explores the design of stacks from the point of view of the downwind observer whose task is to determine the connection between stack design, process emissions, meteorology, and, most important, environmental effects. Stacks must be designed to specifications based on meteorological conditions and environmental air quality standards, which may be quite umelated to process requirements... 

The principal factors which must be accounted for when designing a stack for air pollution control purposes are the dispersion and transport of the pollutants and the performance criteria against which the stack will be compared. These factors include (1) air quality standards, (2) meteorological conditions, and (3) topographical peculiarities. 

Any stack should be designed based on a knowledge of prevailing meteorological conditions and stack emission criteria based on years of operating... 

Annual meteorological data from designated regional stations. 

Data are provided as measured data or prepared data, representing typical data for a period of several years. Design reference years (DRY) established using methods developed with the framework of the lEA (International Energy Agency) represent characteristic data for a period of 10 years, condensed into a one-year data set. Internal coherence, e.g., between solar irradiation and air temperature, is maintained. For the United States, typical meteorological year (TMY) files are based on measurements in the period 1954 through 1972. 

Design wet bulbs can be determined from published meteorological data for the area concerned. The difficulty is deciding how to relate the annual coverage to the tower performance at any given time. 

Elicks BB, Hosker Jr RP, Meyers TP, Womack JD. 1991. Dry deposition inferential measurement techniques. I. Design and tests of a prototype meteorological and chemical system for determining dry deposition. Atmos Environ 25A 2345-2359. 

A column must be designed to withstand the highest wind speed that is likely to be encountered at the site during the life of the plant. The probability of a given wind speed occurring can be predicted by studying meteorological records for the site location. 

We have designed and built a microprocessor-based Data Acquisition System for radon research that is currently being used for field studies. Among other things the system will be used to monitor radon levels in conjunction with other meteorological data in a controlled space over relatively long periods of time. 

As noted by Wolman ( 3), educational institutions are continually asked to prepare those who will search for solutions of societal problems. Problems in the real world do not separate nicely into "disciplines". We do not see the "botany problem", or the "meteorology problem", or the "chemical engineering problem", as such. Rather, we see a minor by-product from a facility designed by a chemical engineer. Released, it is transported by meteorological processes, and becomes of concern because a botanist foresees ecological damage as a consequence of its downwind presence. Thus while disciplines and departments in universities are an administrative convenience and provide a perhaps needed foundation for specialized research and education, educational institutions also must address problems which do not fit nicely into present disciplinary units. 

The fundamental elements of deterministic models involve a combination of chemical and meteorologic input, preprocessing with data transmission, logic that describes atmospheric processes, and concentration-field output tables or displays. In addition to deterministic models, there are statistical schemes that relate precursors (or emission) to photo-chemical-oxidant concentrations. Models may be classified according to time and space scales, depending on the purposes for which th are designed. 

Several generalizations can be made about aerosol characterization study design based on past experience. Existing data should be used to obtain an understanding of the area under study. These data include historical aerosol and gas concentrations, meteorological data, emissions inventories, chemical and microscopical analyses, and the results of dispersion modeling. 

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