Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers (open access)

Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers

An investigation of available data on the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on Ocean Thermal Energy Conversion (OTEC) heat exchangers has been carried out. Pertinent oceanographic data is lacking at or near potential OTEC sites for the calculation of the degree of saturation of seawater with respect to calcium carbonate. Consequently, only ''extrapolated'' saturation values can be used. These indicate that near surface seawater is probably supersaturated, with respect to the calcium carbonate phases calcite and aragonite, at all potential OTEC sites. The deep seawater that would be brought to the surface at the potential Atlantic Ocean sites is also likely to be supersaturated with respect to calcium carbonate. The deep seawater at the potential Pacific Ocean sites may be slightly undersaturated. The fact that OTEC heat exchangers will be operating in seawater, which is supersaturated with respect to calcium carbonate, means that if nucleation of calcite or aragonite occurs on the heat exchanger surfaces, significant growth rates of calcium carbonate scale may be expected. The potential for calcium carbonate nucleation is highest at cathodic metal surface locations, which are produced as the result of aluminum corrosion in seawater. …
Date: April 5, 1978
Creator: Morse, J. W.; de Kanel, J. & Craig, Jr., H. L.
System: The UNT Digital Library
Solar central receiver prototype heliostat. Interim technical progress report (open access)

Solar central receiver prototype heliostat. Interim technical progress report

The objective of Phase I of this project is to support the Solar Central Receiver Power Plant research, development and demonstration effort by: (1) Establishment of a heliostat design, with associated manufacturing, assembly, installation and maintenance approaches, that, in quantity production will yield significant reductions in capital and operating costs over an assumed 30 year plant lifetime as compared with existing designs. (2) Identification of needs for near term and further research and development in heliostat concept, materials, manufacture, installation, maintenance, and other areas, where successful accomplishment and application would offer significant payoffs in the further reduction of the cost of electrical energy from Solar Central Receiver Power Plants. The Phase I study will define a low-cost heliostat preliminary design and the conceptual design of a heliostat manufacturing/installation plan which will result in low life cycle cost when produced and installed at high rate and large quantities for commercial Solar Central Receiver Power Plants. The study will develop the annualized life cycle cost and the performance of heliostats for a 30 year plant life, for each of three rates of continuous production and installation. The three specified rates are 25,000, 250,000, and 1,000,000 heliostats per year. The analysis of these …
Date: April 5, 1978
Creator: unknown
System: The UNT Digital Library
Development and testing of shingle-type solar cell modules. Quarterly report No. 3 (open access)

Development and testing of shingle-type solar cell modules. Quarterly report No. 3

The fabrication and testing phase of the program to develop a shingle-type solar cell module is well underway. Six modules are currently being subjected to a qualification testing program which consists of both thermal cycling and humidity exposures followed by a mechanical integrity test to simulate wind loads. Fabrication of the remainder of the 50 deliverable modules is proceeding.
Date: April 5, 1978
Creator: Shepard, N.F.
System: The UNT Digital Library
Experimental determination of kerma factors at E/sub n/ approx. = 15 MeV (open access)

Experimental determination of kerma factors at E/sub n/ approx. = 15 MeV

Experimental values for the kerma per unit fluence at the neutron energy, E/sub n/ = 15 MeV, have been determined for graphite, Mg, and Fe. Ion chambers of small size with walls of these materials were employed, and were filled with a variety of gases--N/sub 2/, CO/sub 2/, Ne, Ar, Kr, and Xe. A calibrated neutron source was employed, allowing a straightforward determination of the kerma per unit fluence.
Date: April 5, 1978
Creator: Goldberg, E.; Slaughter, D.R. & Howell, R.H.
System: The UNT Digital Library
Preliminary definition of Barstow standard cloud model (open access)

Preliminary definition of Barstow standard cloud model

The motion of cloud shadows across a collector field for a central receiver solar power plant can affect the design of such a facility. Cloud models were developed to be used for basis of design in technology areas. The first effect, that of the temperature gradient, is simulated by postulating the worst case cloud situation. The cyclic effects require realistic cloud shadow time histories for simulation. Cloud shadow models were developed to determine probable cloud type, the cloud area and shape, cloud velocity and cloud-to-cloud spacing. The probability of cloud occurrence is estimated. A collector field computer program is run to determine the effect of cloud variables on collector field power delivery capability. Recommendation of cloud models to be used for basis of design are then made.
Date: April 5, 1978
Creator: unknown
System: The UNT Digital Library
Legal Right Of An Adopted Child To Learn The Identity Of His Or Her Natural Parents (open access)

Legal Right Of An Adopted Child To Learn The Identity Of His Or Her Natural Parents

This report consists of legal right of an adopted child to learn the identity of his or her natural parents.
Date: April 5, 1978
Creator: Reimer, Rita Ann
System: The UNT Digital Library
Analysis of advanced conceptual designs for single-family-sized absorption chillers. Semi-annual report (open access)

Analysis of advanced conceptual designs for single-family-sized absorption chillers. Semi-annual report

The objective of the research program is to develop and analyze new concepts for absorption cycles to improve the performance or reduce the cost (or both) of a 3-ton absorption chiller that can be used with solar-collected heat. New refrigerant-absorbent pairs, additives to currently used refrigerant-absorbent pairs, and modifications to the cycle are being investigated. For the initial analyses the use of a fluid at 160 to 230/sup 0/F from a solar collector as a heating source is assumed. In the initial analyses the chiller is to provide chilled water at 45/sup 0/F at full load; alternatively, if a new refrigerant-absorbent pair appears to be amenable for direct cooling of the occupied space, the temperature of the evaporator is to be 45/sup 0/F. Both water cooling and air cooling of the absorber and the condenser are being studied. The use of ambient air at 95/sup 0/F dry bulb and 75/sup 0/F wet bulb temperatures is assumed. With the water-cooled cycles, the initial and operating costs of a properly sized cooling tower will be included. The research consists of five principal tasks: (a) acquisition of information for analysis, (b) definition of criteria for selection of promising refrigerant-absorbent pairs, additives for currently …
Date: April 5, 1978
Creator: unknown
System: The UNT Digital Library