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Chapter, J. J.

Publications and source records attributed to Chapter, J. J..

High-voltage dc power processing thermal control and packaging techniques

The power processor operates in several modes, delivering up to 100 amperes of regulated electrical power, operating at input voltages to 375 volts with outputs controlled by an integral microprocessor. Several alternative packaging concepts are discussed and evaluated. High-voltage design applications, power stage interconnection and EMI considerations are also discussed. Preliminary thermal analyses were performed and the results presented for each conceptual approach with parametric study results given for the selected concept.

Chapter, J. J.

Large Space Telescope support systems module thermal control

In 1982, an unmanned three-meter class Cassegrainian telescopic system referred to as the Large Space Telescope (LST) will be placed in earth orbit by the Shuttle. The LST consists of a telescope system and surrounding support structure that is referred to as the support system module (SSM). This paper summarizes the thermal control subsystem for several candidate SSM designs. Major emphasis has been given to the LST/SSM design concept that includes a thermally isolated aft cylinder compartment that contains subsystem components. Requirements, interfaces and thermal math modeling methods are presented. Analysis results demonstrate that a cold-biased thermal design using electrical heaters is promising.

Chapter, J. J.

Spacecraft thermal environments.

Definitions are given for spacecraft-surface thermal environment characteristics. Lumped-parameter thermal network modeling techniques are derived for spacecraft thermal environment analysis. The application of these techniques to thermal/vacuum testing is described. A major computer program required by these techniques is outlined. It is noted that this approach has been used to determine thermal environments for the Skylab ATM.

Chapter, J. J.