Kitts' Notes from Diaz-Aguado guest lecture

Quick review/mention of:

- conduction/radiation (mentioned approx for conduction w/honeycomb & contact conduction, challenge of view factors/geometries)

- thermal environment w/sources of sun, albedo, Earth IR along w/internal diss; load from sun and earth w/variation, approximating albedo, beta angle issue to capture orbit effects

Examples - includes several challenging non-Earth orbiting missions

- IRIS: hot/cold/nominal cases, operating/non-operating cases, loads from each source

- LADEE - moon mission, mission phases, moon ir/albedo

- MAVEN - Mars mission, mission phases

- Solar Probe Plus - massive direct solar heat load

Thermal Design Strategies

- passive design approach

- cold bias approach

- active cooling: thermoelectrics, cryogenics

Thermal Design Tools/Components

- MLI blankets - effective emissivity

- kapton heaters - good rules of thumb for use

- surface finishes; a/e ratio, degradation challenges

- material choices to vary conductance

- cooling: heat pipes, cryo coolers (typical for IR sensors)/thermoelectic coolers (usually for small CCDs)

- temperature sensors/thermostats

Thermal Analysis

- examples of different tools

- examples from different missions

Thermal Testing

- thermal imagers to see hot spots

- cycling, soaks, thermal vac, thermal balance to validate/compare w/model

- use of margins

- different sets of limits: operating and survival

- bake-out - evaporates captured water, force some level of outgassing, etc..... "cleans" your satellite

- chambers

- heater testing/sizing

Future concepts

- variable surface emittance - electrochromic

- bio-inspired heat transfer paths

- laser sintered heat pipes (e.g., "printed")

- thermal conductive straps

- thermal capacitance via phase change properties of materials like paraffin