1. AAE450 Senior Spacecraft Design Rick Hutchings Week 2: January 25 th, 2007 Thermal Control Thermal Control Systems for TV

2. AAE450 Senior Spacecraft Design Thermal Control Systems Types of Systems –Passive Coldplate Electrical Equipment Radiator – Active Radiator Coldplate Electrical Equipment Figures based on Fischer, ref 1

3. AAE450 Senior Spacecraft Design Active Thermal Control Mass (kg)Power (kW)Volume(m 3 ) Heat Exchangers 92.25 0.24 Coldplates 240.00 0.56 Pumps with Accumulator 528.001.271.87 Plumbing and Valves 439.21 Instruments and Controls 146.40 Fluids 146.40 Radiators 2067.84 15.30 Total 3660.111.2717.97

4. AAE450 Senior Spacecraft Design References 1)Fischer, Mark. Thermal Control. Feb 1995. University of Texas. 21 Jan 2007. 2)Larson, Wiley and Pranke, Linda. Human Spaceflight Mission Analysis and Design. St. Louis: McGraw-Hill Companies (Pg. 513-537) 3)“Project Legend.” Spring 2005 Purdue University. 5 Jan 2007 (Pg. 285 289) <https://engineering.purdue.edu/AAE/Academics/Courses/ aae450/2005/spring>

5. AAE450 Senior Spacecraft Design Back-up Slides Mass (kg)Power (kW)Volume(m 3 ) Heat Exchangers 17 + 0.25 * capacity in kW0 0.016 + 0.0012 * capacity in kW Coldplates12 * capacity in kW00.028 * capacity in kW Pumps with Accumulator 4.8 * loop capacity in kW0.023 * loop capacity in kW0.017 * loop capacity in kW Plumbing and Valves Add 15% to active systemNegligible Instruments and Controls Add 5% to active systemNegligible Fluids Add 5% to active system0Negligible Heat Pumps8 * capacity in kWVariesNegligible Fixed Radiators5.3 per m 2 Negligible0.02 per m 2 From Table 16-7 in Larson, Wiley, and Pranke, Linda, ref. 2

6. AAE450 Senior Spacecraft Design Passive –Heat radiated at Q = A*s*e*h*(T r 4 - T e 4 ) s = Boltzman’s Constant (5.67E-8 W/(m 2 -K 4 )) e = Surface emissivity (0.9 for radiators) h = Radiator efficiency factor (assumed 0.9) A = 55000W/(5.67E-8*0.9*0.9*(300^4-10^4) = 147.85 m 2

7. AAE450 Senior Spacecraft Design A = Q/ q q: heat rejection rate(W/m 2 ) Q: heat load = 55000/171 =321.64m 2