Engineering topics

Hammel, R. L.

Publications and source records attributed to Hammel, R. L..

9 records

NASA NTRS1976

Space Processing Applications - Designing the initial space transportation system payloads capability

A review is presented of the broad objectives identified by the U.S. Space Processing Applications program. A description is given of the types of materials to be considered, taking into account aspects of crystal growth, questions of purification and separation, mixing, solidification, and processes in fluids. The program requirements are discussed, giving attention to time in space, energy, research and development payload equipment design efforts, design payloads, early mission automated payloads, and early mission manned payloads.

Hammel, R. L.↗

NASA NTRS1974

Space processing applications payload equipment study. Volume 1: Executive summary

A study was conducted to derive and collect payload information on the anticipated space processing payload requirements for the Spacelab and space shuttle orbiter planning activities. The six objectives generated by the study are defined. Concepts and requirements for space processing payloads to accommodate the performance of the shuttle-supported research phase are analyzed. Diagrams and tables of data are developed to show the experiments involved, the power requirements, and the payloads for shared missions.

Hammel, R. L.↗

NASA NTRS1974

Space processing applications payload equipment study. Volume 2B: Payload interface analysis (power/thermal/electromagnetic compatibility)

As a part of the task of performing preliminary engineering analysis of modular payload subelement/host vehicle interfaces, a subsystem interface analysis was performed to establish the integrity of the modular approach to the equipment design and integration. Salient areas that were selected for analysis were power and power conditioning, heat rejection and electromagnetic capability (EMC). The equipment and load profiles for twelve representative experiments were identified. Two of the twelve experiments were chosen as being representative of the group and have been described in greater detail to illustrate the evaluations used in the analysis. The shuttle orbiter will provide electrical power from its three fuel cells in support of the orbiter and the Spacelab operations. One of the three shuttle orbiter fuel cells will be dedicated to the Spacelab electrical power requirements during normal shuttle operation. This power supplies the Spacelab subsystems and the excess will be available to the payload. The current Spacelab sybsystem requirements result in a payload allocation of 4.0 to 4.8 kW average (24 hour/day) and 9.0 kW peak for 15 minutes.

Hammel, R. L.↗

NASA NTRS1974

Space processing applications payload equipment study. Volume 2D: SPA supplemental power and heat rejection kit

The design and application of a supplementary power and heat rejection kit for the Spacelab are discussed. Two subsystems of electric power and thermal control were analyzed to define the requirements for the power and heat rejection kit (PHRK). Twelve exemplary experiments were defined and power timelines were developed. From these timeline, the experiment requirements for sustained power, peak power, and energy were determined. The electrical power subsystem of the PHRK will consist of two fuel cells, oxygen and hydrogen reactant tank assemblies, water storage tanks, plumbing, cabling, and inverters to convert the nominal 28 volt dc fuel cell output to ac power.

Hammel, R. L.↗

NASA NTRS1974

Space processing applications payload equipment study. Volume 3: Programmatics

The programmatic aspects of the space processing applications program and the methods of accommodating SPA payloads aboard the Shuttle/Spacelab host vehicle are discussed. An examination of the NASA traffic model shows that there exists a potential for 178 SPA payloads from the overall total of 727 flights specified. This could represent up to one quarter of the total shuttle flights during the 12-year-long period covered by the traffic model. The SPA payload will range from austere for shared flight opportunities to dedicated where space processing will encompass the total flight payload allocations. The major modes of use to SPA will include dedicated Spacelab missions, shared Spacelab missions and shared automated payloads attached to the pallet with the necessary control and display equipment in the host vehicle. Several layout drawings and artist's renderings have been completed to illustrate the various potential configurations available to accommodate the SPA payload equipment.

Hammel, R. L.↗

NASA NTRS1974

Requirements and concepts for space-processing payloads

The definition of facilities which will serve the research needs of a large group of users is given. These facilities (payloads) are derived by several combinations of items from a large inventory of modular, reusable, research equipment which enables ready response to many flight opportunities. Workable concepts were prepared and submitted to the Spacelab design activity. These designs permit the flying of either partial or dedicated payloads. The technical integrity of the modular approach to payload design/integration and the utility of commercial equipment technology are also discussed.

Taylor, K. R.↗

NASA NTRS1974

Space processing payloads for Spacelab

Discussed are the definitions of facilities which will serve the research needs of a large group of users. These facilities (payloads) are derived by several combinations of items from a large inventory of modular, reusable, research equipment which enables ready response to many flight opportunities. Workable concepts have been prepared and submitted to the Spacelab design activity. These designs permit the flying of either partial or dedicated payloads. The technical integrity of the modular approach to payload design/integration and the utility of commercial-equipment technology are also addressed in this paper.

Taylor, K. R.↗

NASA NTRS1974

Space processing payloads for the Space Shuttle era

This paper discusses the definition of facilities which will serve the research needs of a large group of users. These facilities (payloads) are derived by several combinations of items from a large inventory of modular, reusable research equipment, enabling us to respond to many flight opportunities. Workable concepts have been laid out and inputted into the Spacelab design activity. These designs permit the flying of either partial or dedicated payloads. Also addressed in this paper are the technical integrity of the modular approach to payload design and integration, and the utility of commercial equipment technology.

Taylor, K. R.↗

NASA NTRS1971

Extended ion pumped vacuum friction test

Boundary layer friction data under ion pumped vacuum was taken for sixteen material couples. The test series was an extension of a previous study of the effects of modified ion pumped environments. Sliding distances imposed in the present effort greatly exceeded any studied in the previous contiguous, flight or ground tests. Wear out of specific couples, in particular, thin film lubricants was noted. The behavior of the test hardware including wear out of the mechanisms was noted. As a result, the impact of test interruption was observed for several test couples. Recovery of the friction upon re-establishing sliding in vacuum was generally rapid. The results of the extended sliding study reinforce the previous conclusion that sliding distance (mechanical history) is the primary factor in establishing the force limiting boundary layer friction. General friction value under the extended sliding confirm those observed in previous orbital and the related ground test studies.

Hammel, R. L.↗