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Demorest, K. E.

Publications and source records attributed to Demorest, K. E..

17 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Parameters affecting electrostatic cooling

A high voltage electrostatic field is discussed which enhances the rate of normal convective cooling. This cooling rate is a function of starting temperature and voltage applied, and an inverse function of atmospheric pressure or the heat capacity of the surrounding media. It appears that the cooling rate is also a function of current flow; however, additional work is needed to separate other variables from the effect of current flow. The maximum increase in heat loss over the normal convective cooling was approximately 0.167 C/sec (0.3 F/sec) at 316 C (600 F) and 20,000 V. From the data taken it is assumed that the addeded rate of cooling would be increased with higher temperatures and higher voltages. It appears that a high voltage field disrupts the molecular layer of air surrounding a hot body and increases the rate of convective cooling.

Demorest, K. E.↗
NASA NTRS1976

An evaluation of grease type ball bearing lubricants operating in various environments /Status report no. 2/

Because many future spacecraft or space stations will require mechanisms to operate for long periods of time in environments which are inimical to most bearing lubricants, a series of tests has been started to evaluate 25 grease type lubricants in R-4 size bearings in five different environments for a 1 year period. Four repetitions of each test are made to provide statistical samples. These tests will be used to select from two to five lubricants for 5 year tests in the same environments. At the present time, approximately 30 test sets have been completed and 25 sets are underway. To date, best results in all environments have been obtained with a high viscosity index perfluoropolyether grease.

Demorest, K. E.↗
NASA NTRS1976

An evaluation of grease ball bearing lubricants in vacuum

Because many future spacecraft will require mechanisms to operate for long periods of time in environments which are inimical to most bearing lubricants, a series of tests has been started to evaluate 25 grease type lubricants in R-4 size bearings in vacuum at ambient temperature for a 1 year period. Four repetitions of each test are made to provide statistical samples. These tests will be used to select from two to five lubricants for 5 year tests in the same environment. At the present time fifteen test sets have been completed and five sets are being tested. The best results to date have been obtained with perfluoropolyether greases.

Demorest, K. E.↗
NASA NTRS1970

Comparison of release torques of tightened bolts in vacuum and air

Various combinations of stainless steel, mild steel, and aluminum bolt-nut couples are tightened to 60 lb-ft in partial vacuum and in air. Results are given for tests with and without two lubricants /a fluorosilicone and a sodium silicate bonded dry-film/.

Demorest, K. E.↗
NASA NTRS1969

Bolt torque tests in vacuum

Test equipment and tests to determine effects of vacuum environment on release torque of threaded fasteners

Demorest, K. E.↗
NASA NTRS1969

Self-lubricating gear

Self-lubricating gear, designed for long term operation in a vacuum at high, low, and ambient temperatures, is constructed of alternating layers of metal and a dry lubricant material, such as polytetrafluoroethylene, with a suitable reinforcing material bonded into a laminated composite unit, which is machined to form a standard gear.

Demorest, K. E.↗