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The Portable Life Support System (PLSS) provides a suitable environment for the astronaut in the Extravehicular Mobility Unit (EMU), and the heat rejection system controls the thermal conditions in the space suit. The current PLSS sublimates water to the space environment; therefore, the system loses mass. Since additional supplies of fluid must be available on the Space Shuttle, NASA desires a closed heat rejecting system. This document presents the embodiment design for a radiative plate heat rejection system without mass transfer to the space environment. This project will transform the concept variant into a design complete with material selection, dimensions of the system, layouts of the heat rejection system, suggestions for manufacturing, and financial viability.

Astronauts frequently use a variety of hand tools during space missions, especially on repair missions. A toolbox is needed to allow storage and retrieval of tools with minimal difficulties. The toolbox must contain tools during launch, landing, and on-orbit operations. The toolbox will be used in the Shuttle Bay and therefore must withstand the hazardous space environment. The three main functions of the toolbox in space are: to protect the tools from the space environment and from damaging one another, to allow for quick, one-handed access to the tools; and to minimize the heat transfer between the astronaut's hand and the tools. This proposal explores the primary design issues associated with the design of the toolbox. Included are the customer and design specifications, global and refined function structures, possible solution principles, concept variants, and finally design recommendations.

It is shown that for an axially periodic column of magnetofluid driven by an applied axial electric field, the total rate of energy dissipation (Ohmic plus viscous) can be lowered by permitting a helical component with vortical flow in the solution. The principle of minimum energy-dissipation rate suggests that this partially helical state will be preferred to the axisymmetric one that exists for the same parameters. The result is consistent with the repeated appearance of such partially-helical states in several fully three-dimensional numerical computations and is not inconsistent with the data from some confinement experiments.

Minimum dissipation rate states are explored for a current-carrying channel of magnetofluid, supported by a dc magnetic field and driven by an applied electric field. The minimization is carried out subject to the constraints of constant axial (toroidal) magnetic flux and constant time-averaged rate of supply of magnetic helicity. The solutions of the resulting Euler-Lagrange equations are sensitive to boundary conditions on the current density j. One set of boundary conditions on j leads to the same consequences as Taylor's 'minimum-energy' theory. A different set leads to significantly different consequences, including a departure from the 'force-free' magnetic profile and a toroidal component of current density that does not reverse at the wall when the toroidal magnetic field reverses.