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Engineering topics

Howell, J. R.

Publications and source records attributed to Howell, J. R..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Hydrogen production econometric studies

The current assessments of fossil fuel resources in the United States were examined, and predictions of the maximum and minimum lifetimes of recoverable resources according to these assessments are presented. In addition, current rates of production in quads/year for the fossil fuels were determined from the literature. Where possible, costs of energy, location of reserves, and remaining time before these reserves are exhausted are given. Limitations that appear to hinder complete development of each energy source are outlined.

Howell, J. R.↗
NASA NTRS1972

System design of a near-self-supporting lunar colony.

Concepts for expanding a 12-man lunar surface base to a more permanent colony of about 180 persons are studied. Guidelines for the colony design are that the colony must perform a useful function, and that design should maximize use of lunar materials and minimize requirements of resupply from the earth. The first use of lunar materials should be for oxygen production, to achieve which large electrical or thermal power inputs are necessary. Some of the efforts which should be directed toward food and plant growth are considered, and those factors from life support and waste control which bear further study are examined. Aspects of power generation, mining, and construction are discussed.

Howell, J. R.↗
NASA NTRS1972

Thermal radiation heat transfer.

A comprehensive discussion of heat transfer by thermal radiation is presented, including the radiative behavior of materials, radiation between surfaces, and gas radiation. Among the topics considered are property prediction by electromagnetic theory, the observed properties of solid materials, radiation in the presence of other modes of energy transfer, the equations of transfer for an absorbing-emitting gas, and radiative transfer in scattering and absorbing media. Also considered are radiation exchange between black isothermal surfaces, radiation exchange in enclosures composed of diffuse gray surfaces and in enclosures having some specularly reflecting surfaces, and radiation exchange between nondiffuse nongray surfaces. The use of the Monte Carlo technique in solving radiant-exchange problems and problems of radiative transfer through absorbing-emitting media is explained.

Siegel, R.↗
NASA NTRS1970

Directional control of radiant heat

Surface with grooves having flat bases gives directional emissivities and absorptivities that can be made to approximate a perfect directional surface. Radiant energy can then be transferred in desired directions.

Howell, J. R.↗