Report of NPSAT1 battery thermal contact resistance testing, modeling and simulation
MetadataShow full item record
Thermal modeling is an important part of spacecraft design, especially where critical components have narrow operating temperature limits. For the Naval Postgraduate School’s NPSAT1 spacecraft, the lithium ion battery is the spacecraft component with the smallest temperature range of 0°C to 45°C during operation. Thermal analysis results, however, can only provide adequate results if there is sufficient fidelity in thermal modeling. Arguably, the values used in defining thermal coupling for components are the most difficult to estimate because of the many variables that define them. This document describes the work performed by the authors starting in the 2012 winter quarter as part of the SS3900 directed study course. The objectives of the study were to determine an adequate thermal model of the NPSAT1 battery as a lumped capacitance model, and an appropriate value of thermal resistance between the battery and its mounting surface for three thermal interfaces: metal-to-metal (bolted interface), Kapton®, and Chotherm® 1671. These objectives were performed through testing in a thermal-vacuum chamber with controlled boundary conditions. Modeling and simulation using the NX I-DEAS Thermal Model Generator software was performed to duplicate the test results in simulation. Agreement between the simulations and testing was achieved with differences ranging between +4°C and -8°C for the metal-to-metal interface, to as low as +2°C to -1°C using an elastomeric thermal interface material (Chotherm® 1671). The test-validated thermal model can then be incorporated into the larger NPSAT1 thermal model tospecifically evaluate battery temperatures for various flight operations.
NPS Report NumberNPS-SP-12-002
Showing items related by title, author, creator and subject.
Operational testing and thermal modeling of a TOPAZ-II single cell thermionic fuel element test stand Benke, Steven M. (Monterey, California. Naval Postgraduate School, 1994-12);A TOPAZ-2 Thermionic Fuel Element (TFE) test stand is under study at the TOPAZ International Program. Extensive cross-sectional drawings of this system are presented along with detailed descriptions of its construction. A ...
Gruhlke, Martin (Monterey, California. Naval Postgraduate School, 2003-05-05); NPS-SP-03-001The thermal control system of a spacecraft is used to maintain all subsystems within their temperature limits. It must be able to deal with different operational states and orbital environments. Theory provides knowledge ...
Rahn, Sajoscha (Monterey, California. Naval Postgraduate School, 2012-07); NPS-SP-12-001The purpose of this thesis is to validate a finite element model of the small satellite NPSAT1. A modal test of this satellite will be conducted and the results will be correlated to the FEM simulation results. Furthermore, ...