Nozzle fields

Complete Harris Hydro Unit. Alternator, housing, nozzles, field eontrol panel (meter and rheostat). Uses efTicient Motorcrafl Ford alternator. Custom-eonfigured with windings optimized for your sites head, water volume, and battery voltage. 1 nozzle (up to 20 gpm), 820. 2-nozzle (up to 40 gpm), 925. Four nozzle (up to 80 gpm), 1,080. (Performance limit about 25A at 12,24, or 48V.)... 

There are basically three possible designs of nozzle arrays which differ with regard to the spent flow of the air (Fig. 1.2). In a field of individual nozzles the aft-can flow unimpeded between almost all nozzles however, in a hole channel the air can flow only between those above. In a perforated plate the air can only continue to flow laterally and then escape. Hole channels and perforated plates are easier to produce than single nozzles, as they only require holes to be perforated. However, the heat transfer is the highest for nozzle fields and the lowest for perforated plates, as will be subsequently shown. 

In the case of larger areas to be cooled or heated, several nozzles in a so-called nozzle field must be used. Ho vever, the relative nozzle pitch t/d must now be taken into consideration as an additional geometric parameter. Initially, arrays of single nozzles are discussed, and it is assumed that the pitch is equal in both directions. 

The Nusselt functions for the single nozzle are summarized in Tab. 1.1, and for the nozzle fields in Tab. 1.2. The Nusselt and Remolds numbers are defined with the inner nozzle diameter d regarding round nozzles, and with the width s regarding slot nozzles. The exponent of the Reynolds number in correlations for the average... 

Tab. 1.2 Nusselt functions for nozzle fields impinging flat surfaces.

The highest convective heat transfer coefficients in drying processes can be achieved using nozzle fields, and drying is strongly intensified in such a field. As a consequence, the heat transfer area, and therefore the size of the apparatus, can be reduced, saving investment costs. 

The most difficult part of a field test is the flow meter, if it wasn t planned in the construction phase. There is no way to simulate a meter run if you don t have the proper pipe length. Figure 10-8 is an example of the requirements. An ASME long radius flow nozzle is preferred by the author, though a short throat venturi will do. The probability is that an orifice is all that will be available. It should be examined before and after the test to verify not only the bore diameter, but the finish. The bore should... 

Flow of gases and vapors (compressible fluids) through nozzles and orifices. (For flow field importance see References [31]). From [3] ... 

Introducing the nozzle flow coefficient of 0.95 and using field system of units, Equation 4-117 becomes... 

The development of new alloys in new fields for example the development of molybdenum and tungsten with iron, cobalt or nickel for coating of dies and nozzles, or the development of palladium-nickel alloy as an alternative to gold for connectors. 

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