Prediction of Satellite Temperature During an Orbit of a CubeSat

Author

• Michael Reynolds, University of South Alabama

Date of Award

7-2026

Document Type

Undergraduate Thesis

Degree Name

BS

Department

Mechanical Engineering

Faculty Mentor

Joseph Richardson, Ph.D

Advisor(s)

Anh-Vu Phan, Ph.D. and Edmund Spencer, Ph.D.

Abstract

This thesis develops a thermal-simulation strategy for predicting CubeSat component temperatures, applied to Jag-Sat-1, a CubeSat developed at the University of South Alabama and deployed from the International Space Station in 2022. The orbit was reconstructed from two-line element (TLE) data using simplified general perturbations (SGP4) propagation, and spacecraft attitude was recovered from onboard gyroscope measurements. Sunlight, penumbra, and umbra intervals were computed geometrically, and the external radiative environment — direct solar, Earth infrared, and albedo heat fluxes — was modeled using orientation-dependent view factors. These time-varying fluxes drove a transient finite-element thermal simulation of the full satellite geometry in ANSYS Mechanical, including internal heat generation from major subsystems. The model was verified against a closed-form flat-plate solution and also compared with 23 days of flight telemetry. Because telemetry was downlinked only during ground-station passes, the sampling rate was insufficient to resolve the 94-minute orbital thermal cycle; validation was therefore performed at the envelope level, where simulated battery temperatures reproduced the measured range and long-term trends. The resulting framework provides a basis for the thermal design of future CubeSat missions, with higher-cadence temperature logging recommended to enable waveform-level validation.

Recommended Citation

Reynolds, Michael, "Prediction of Satellite Temperature During an Orbit of a CubeSat" (2026). Honors Theses. 170.
https://jagworks.southalabama.edu/honors_college_theses/170