Gaps in Thermal Design Guidelines in Goddard Space Flight Center GOLD Rules

Date

2018-07-08

Journal Title

Journal ISSN

Volume Title

Publisher

48th International Conference on Environmental Systems

Abstract

The GSFC (Goddard Space Flight Center) GOLD Rules (Goddard Open Learning Design; GSFC-STD-1000) provide a reasonably comprehensive list of guidelines for the design and testing of spacecraft and instruments based on the long heritage of successful GSFC missions. In general, all GSFC missions are required to comply with the GOLD Rules across a number of subsystems or to seek waivers to particular GOLD rules where compliance is not practical, either due to the risk posture of a mission or the cost and/or schedule associated with compliance. In thermal subsystems, GOLD Rules are applied to design margins throughout the project life cycle and include temperature margins, heater power margins, and two-phase transport margins. However, no explicit guidance is provided for two thermal design aspects: heater control authority (for stability requirements) and cryogenic design margins (which are often not reasonable to express in terms of temperatures). This can lead to ambiguity and inconsistency among projects when demonstrating GOLD Rules compliance. Two current GSFC projects, TIRS-2 (Thermal InfraRed Sensor 2) and WFIRST (Wide Field InfraRed Survey Telescope), are both missions with cryogenic aspects and active thermal control for stability. This paper seeks to outline the characterization of cryogenic margins during the design process for TIRS-2 and WFIRST as well as the project derived guidelines for heater control authority margin. This effort serves as potential first steps for updating the GOLD Rules to address these two areas in guiding thermal designs at GSFC.

Description

Hume Peabody, NASA
Sharon Peabody, Edge Space Systems
ICES105: Thermal Standards and Design/Development Practices
The 48th International Conference on Environmental Systems was held in Albuquerque, New Mexico, USA on 08 July 2018 through 12 July 2018.

Keywords

Thermal, Design Margin, Heater Control Authority, Cryogenic Margins, TIRS, WFIRST

Citation