1. AAE450 Spring 2009 Lunar Lander Power Systems Thursday March 12 th Adham Fakhry Power Group Lunar Lander Descent Night Thermal

2. AAE450 Spring 2009 Final Power Systems [Adham Fakhry] [POW] 2 100 gram LanderMass (kg)Dimensions (m)Cost ($) Solar Cells2.00.785 m 2 250,000 Batteries0.4220.1016 X 0.0252 X 0.07091500 DC-DC Converters0.7250.06 X 0.05 X 0.0451,000 PCDU (Power Conditions and Distribution unit) 1.90.033 X 0.033 X 0.03312,000 10 kg LanderMass (kg)Dimensions (m)Cost ($) Solar Cells2.00.785 m 2 250,000 Batteries0.6450.142 X 0.0534 X 0.15022000 DC-DC Converters0.8150.06 X 0.05 X 0.0457,500 PCDU (Power Conditions and Distribution unit) 1.90.033 X 0.033 X 0.03312,000

3. AAE450 Spring 2009 Final Power Systems for Arbitrary [Adham Fakhry] [POW] 3 Arbitrary LanderMass (kg)Dimensions (m)Cost ($) Solar Cells2.00.785 m 2 250,000 Batteries0.890.142 X 0.0276 X 0.0952000 DC-DC Converters0.9850.07 X 0.06 X 0.0468,000 PCDU (Power Conditions and Distribution unit) 1.90.033 X 0.033 X 0.03312,000

4. AAE450 Spring 2009 Backup Slide 1: Power Available to the Lander [Adham Fakhry] [POW] 4

5. AAE450 Spring 2009 Backup Slide 2 - Battery Design  Battery is designed for meet three power goals for 100 g Lander: –Delivers 124 W for 250 seconds for operating the Lander engine –Delivers 30 W for 576 seconds of attitude –Delivers 58.4 W for 30 minutes for all communication gear [Adham Fakhry] [POW] 5

6. AAE450 Spring 2009 Backup Slide 3 - Battery Design  Battery is designed for meet three power goals for 10 kg Lander: –Delivers 150 W for 450 seconds for operating the Lander engine –Delivers 30 W for 900 seconds of attitude –Delivers 58.4 W for 30 minutes for all communication gear [Adham Fakhry] [POW] 6

7. AAE450 Spring 2009 Backup Slide 4 - Battery Design  Battery is designed for meet three power goals for Arbitrary Lander: –Delivers 275 W for 500 seconds for operating the Lander engine –Delivers 30 W for 900 seconds of attitude –Delivers 58.4 W for 30 minutes for all communication gear [Adham Fakhry] [POW] 7

8. AAE450 Spring 2009 Backup Slide 5 – Solar Array Deployment [Adham Fakhry] [POW] 8 1.0 m

9. AAE450 Spring 2009 Backup Slide 6: Solar Array sizing  Solar array Calculations:  Dimensions of Solar cells: –Area of Lander roof = π(1/2)2 = 0.785 m2 –Solar efficiency = 300 W/m2 –Potential max power = 235.6 W  Cost of Solar Cells: –Cost of cells per watt = 1000 $/W –Cost of Cells = 235,619.45 = $235,600 –Total cost = $235,600 + 4,400 (for additional costs) = $250,000 [Adham Fakhry] [POW] 9

10. AAE450 Spring 2009 Backup Slide 7: Code for battery  %Lunar Lander Arbitrary case  clc  clear  %Dimensions of Lander/Provided by Ryan Nelson  %du = ; %Upper diameter of lander  %dl =; %Lower diameter of Lander  %h=; %Height of Lander  %SA = ; %Surface Area of Lander   %Solar cells/Data taken from Ian Megginis and from Spectrolabs  mass_density = 2.06; %Mass denisty in kg/m^2  cost_density = 1000; %Cost density in $/W  power_density = 330; %Power density in W/m^2   %area = pi*((du-.2)/2)^2; %Area of Solar Cells in m^2  %mass = area*mass_density; %Mass of solar cells in kg  %power = power_density*area; %Maximum power generated by solar cells in W  %cost = power*cost_density; %Cost of solar cells in $   %Batteries  %Usages are calculated to determine the size needed for battery  %Propulsion  prop_usage = 275;  usage_time_prop = 500*(1/3600); %Usage time in hours for 500 second  w_prop = prop_usage*usage_time_prop; [Adham Fakhry] [POW] 10

11. AAE450 Spring 2009 Backup Slide 8: Code for battery 2  %Communications  comm_usage = 52.4;  usage_time_comm = 0.5; %Usage time is in hours for 1800 s  w_comm = comm_usage * usage_time_comm;   %Propellant  % k=0.005; %Thermal Conductivity of MLI in W/m-K  % t=200/1000; %Thickness of MLI in m  % dt=280.3; %Temperature change in K  % A=0.97; %Area of tanks in m^2  % fuel_usage = k*A*dt/t; %Power usage need for fuel in W  % usage_time_fuel = 250*(1/3600); %Time fuel requires heat in s  % w_fuel =fuel_usage*usage_time_fuel; %Power need to heat fuel in W-hr  w_fuel = 0;   %Attitude  att_usage = 30; %Power used by coolers in W  usage_time_att = 0.25; %For a period of 900 seconds  w_att = att_usage*usage_time_att; %Watt usage in W-hr   %Total  w_total = w_prop+w_comm+w_fuel+w_att  Amp_hour = w_total/3.6 [Adham Fakhry] [POW] 11

12. AAE450 Spring 2009 Backup Slide 7: References  References: –http://www.yardney.com/http://www.yardney.com/ –http://nmp.jpl.nasa.govhttp://nmp.jpl.nasa.gov –http://www.aec- able.com/corpinfo/Resources/ultraflex.pdfhttp://www.aec- able.com/corpinfo/Resources/ultraflex.pdf –http://www.spectrolab.com/http://www.spectrolab.com/ –http://www.mdipower.comhttp://www.mdipower.com [Adham Fakhry] [POW] 12