999 resultados para ground mass


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In the case of suspension flows, the rate of interphase momentum transfer M(k) and that of interphase energy transfer E(k), which were expressed as a sum of infinite discontinuities by Ishii, have been reduced to the sum of several terms which have concise physical significance. M(k) is composed of the following terms: (i) the momentum carried by the interphase mass transfer; (ii) the interphase drag force due to the relative motion between phases; (iii) the interphase force produced by the concentration gradient of the dispersed phase in a pressure field. And E(k) is composed of the following four terms, that is, the energy carried by the interphase mass transfer, the work produced by the interphase forces of the second and third parts above, and the heat transfer between phases. It is concluded from the results that (i) the term, (-alpha-k-nabla-p), which is related to the pressure gradient in the momentum equation, can be derived from the basic conservation laws without introducing the "shared-pressure presumption"; (ii) the mean velocity of the action point of the interphase drag is the mean velocity of the interface displacement, upsilonBAR-i. It is approximately equal to the mean velocity of the dispersed phase, upsilonBAR-d. Hence the work terms produced by the drag forces are f(dc) . upsilonBAR-d, and f(cd) . upsilonBAR-d, respectively, with upsilonBAR-i not being replaced by the mean velocity of the continuous phase, upsilonBAR-c; (iii) by analogy, the terms of the momentum transfer due to phase change are upsilonBAR-d-GAMMA-c, and upsilonBAR-d-GAMMA-d, respectively; (iv) since the transformation between explicit heat and latent heat occurs in the process of phase change, the algebraic sum of the heat transfer between phases is not equal to zero. Q(ic) and Q(id) are composed of the explicit heat and latent heat, so that the sum Q(ic) + Q(id)) is equal to zero.

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In this paper, a ground hydrologic model(GHM) is presented in which the vapor, heat and momentum exchanges between ground surface covers (including vegetation canopy) and atmosphere is described more realistically. The model is used to simulate three sets of field data and results from the numerical simulation agree with the field data well. GHM has been tested using input data generated by general circulation model (GCM) runs for both the North American regions and the Chinese regions, The results from GHM are quite different from those of GHMs in GCMs. It shows that a more active concerted effort on the land surface process study to provide a physically realistic GHM for predicting the exchange between land and atmosphere is important and necessary.

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The water problems confronting Hallandale are similar to those of other coastal cities of southeastern Florida which are undergoing rapid growth with tremendous increase in water demand. The highly permeable Biscayne aquifer underlying the Hallandale area is an excellent source of water; however, the permeable nature of the Biscayne aquifer would permit the intrusion of sea water, if fresh water levels were lowered excessively, as well as the infiltration of urban or industrial contaminants, from land surfaces and surface water bodies. This study is to provide the hydrologic data necessary for proper water resource development and planning in the Hallandale area. (40 page document)

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Ground-water is not widely used in Baker County, but the presence of a high equipotential area in the artesian system beneath the County made it necessary that the resource be understood insofar as this high affected the ground-water resources of Nassau and Duval counties which were being intensively studied and mapped. The method and rates of movement of ground-water from one point to another in the artesian aquifer are understood more fully by use of the data in this report. (PDF contains 30 pages)

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The purpose of this report is to present the results of the initial quantification of background water quality in each of the state's major potable aquifer systems. Results are presented and interpreted in light of the influencing factors which locally and regionally affect ambient ground-water quality. This initial data will serve as a baseline from which future sampling results can be compared. Future sampling of the Network will indicate the extent to which Florida's regional ground-water resources are improving or declining in quality. (Document has 378 pages.)

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The scope of the investigation involved the drilling of test holes and the detailed inventorying of existing wells in order to define the location, depth, potential yield, and chemical quality of the water contained in the shallow aquifer that might be used for the development of a central water-supply system. The field work and collection of data for the investigation covered the period 1961 through 1963. Much of the data collected for the report on the ground-water resources of Collier County (McCoy, 1962) is incorporated into this report. (Document has 36 pages.)

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Charlotte, De Soto, and Hardee counties are east-southeast of Tampa in west-central peninsular Florida, figure 1. In order to plan the future water-resource development of the area, information about the water resources is needed. To meet this need, the Water Resources Division of the U.S. Geological Survey, in cooperation with the Peace River Basin Board of the Southwest Florida Water Management District as part of the statewide cooperative program with the Division of Geology, Florida Board of Conservation, began a continuing hydrologic data collection program in July, 1963, as an initial step in the investigation and evaluation of the groundwater resources of Hardee and De Soto counties. A similar hydrologic data program commenced in Charlotte County in July, 1964. Previous work in Hardee and De Soto counties included a one year reconnaissance by the Division of Water Resources and Conservation, Florida Board of Conservation, which concluded in June, 1963, and resulted in a hydrologic report (Woodard, 1964). As an outgrowth of the hydrologic data program, a Map Series report portraying the chemical character of water in the Floridan aquifer in the southern Peace River basin was prepared in 1967 (Kaufman and Dion). The data contained herein constitute the basis for the Map Series report. Additional selected data, including records of wells and chemical analyses,, on the ground-water resources of the three county area are also included and are published to make the data available. (Document has 28 pages.)

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lGround water in Florida is the principal source of supply for industrial, municipal, agricultural, and domestic uses. During the last half century large developments of ground water have been made, and new developments are currently being addedi However, although problems of supply, some of them critical, have arisen in certain areas, vast quantities of ground water are:yet available for development over a major part of the State. It is quite conceivable that the availability of large developed water resources in Florida, in contrast with the shortages of supply in many other parts of the country, may play a dominant role in the agricultural and industrial growth of the State. (PDF has 15 pages.)