Title:
Spacecraft radiator system and method using east west coupled radiators
Kind Code:
A1


Abstract:
A spacecraft, along with an improved spacecraft radiator system and spacecraft heat dissipation method are disclosed. The spacecraft comprises a body with north, south, east and west facing panels. The spacecraft radiator system comprises one or more heat pipes disposed on each of the east and west facing panels to provide east and west facing radiator panels, heat dissipating equipment selectively mounted on the heat pipes on the east and west facing panels, and one or more coupling heat pipes that thermally interconnect the heat pipes on the east and west facing radiator panels together. By coupling the east and west facing radiator panels together in this manner, they share the heat load. This increases the thermal dissipation capability of the east and west facing radiator panels and radiator system by approximately 50%. This offers a ten-fold increase in the ability to transfer heat from the east to west sides of the spacecraft.



Inventors:
Low, Lenny (Hillsborough, CA, US)
Luong, John (Mountain View, CA, US)
Application Number:
09/823072
Publication Date:
10/03/2002
Filing Date:
03/30/2001
Assignee:
LOW LENNY
LUONG JOHN
Primary Class:
Other Classes:
165/104.33
International Classes:
B64G1/50; F28D15/02; (IPC1-7): F28F1/00; F28D15/00
View Patent Images:
Related US Applications:



Primary Examiner:
RIVELL, JOHN A
Attorney, Agent or Firm:
Joyce Kosinski (Rolling Hills Estates, CA, US)
Claims:

What is claimed is:



1. A spacecraft radiator system for use on a spacecraft having a body and north, south, east and west facing panels, the system comprising: one or more heat pipes disposed on each of the east and west facing panels; heat dissipating equipment selectively mounted on the heat pipes on the east and west facing panels; and one or more coupling heat pipes that thermally interconnect the heat pipes on the east and west facing radiator panels together.

2. The spacecraft radiator system recited in claim 1 wherein the one or more coupling heat pipes comprise loop heat pipes.

3. A spacecraft comprising: a body comprising north, south, east and west facing panels; and a spacecraft radiator system comprising: one or more heat pipes disposed on each of the east and west facing panels; heat dissipating equipment selectively mounted on the heat pipes on the east and west facing panels; and one or more coupling heat pipes that thermally interconnect the heat pipes on the east and west facing radiator panels together.

4. The spacecraft recited in claim 3 wherein the one or more coupling heat pipes comprise loop heat pipes.

5. A spacecraft heat dissipation method comprising the steps of: configuring a spacecraft 10 to have a body with north, south, east and west facing panels, one or more heat pipes disposed on each of the east and west facing panels, heat dissipating equipment selectively mounted on the heat pipes on the east and west facing panels, and one or more coupling heat pipes that thermally interconnect the heat pipes on the east and west facing radiator panels together; launching the spacecraft into orbit; and when in orbit, heat coupled to the one or more heat pipes on the east and west facing panels by the heat dissipating equipment is coupled to the one or more heat pipes of the other of the east and west facing panels.

6. The method recited in claim 5 wherein the one or more coupling heat pipes comprise loop heat pipes.

Description:

BACKGROUND

[0001] The present invention relates generally to spacecraft, and more specifically, to a spacecraft radiator system having coupled east and west facing thermal radiator panels and a spacecraft heat dissipation method.

[0002] The assignee of the present invention manufactures and deploys spacecraft into geosynchronous and low earth orbits. Such spacecraft use one or more radiator systems to dissipate heat generated by equipment on the spacecraft. The radiator systems transfer thermal energy to radiator panels where it is radiated into space.

[0003] Heat pipes connecting north and south radiator panels have heretofore been used. Such structures are disclosed in U.S. patent application Ser. No. 09/377,442, filed Aug. 19, 1999, entitled “Spacecraft Radiator System Using Crossing Heat Pipes”, assigned to the assignee of the present invention, U.S. Pat. No. 3,749,156 issued to Fletcher et al. entitled “Thermal Control System for a Spacecraft Modular Housing”. Radiator panels on the east and west facing panels that are radiatively coupled to the north and south panels are disclosed in U.S. Pat. No. 5,372,183 entitled “Thermal Control Arrangements for a Geosynchronous Spacecraft” issued to Strickberger.

[0004] U.S. Pat. No. 3,749,156 discloses coupling the north south radiator panels and not the east and west panels. Neither U.S. Pat. No. 3,749,156 nor U.S. Pat. No. 5,372,183 disclose or suggest mounting equipment on the east and west panels because of the high incident solar flux. U.S. Pat. No. 5,372,183 discloses radiatively coupling the north, south, east and west panels, but does not mount equipment on the east and west panels nor does he consider using heat pipes to couple the east and west panels together. U.S. Pat. No. 5,372,183 discloses the use of the east and west panels to improve the heat rejection capability of the main north and south payload radiator panels. In contrast, the present invention uses the east and west panels as payload radiators.

[0005] Accordingly, it is an objective of the present invention to provide for heat dissipating apparatus comprising a spacecraft radiator system having east-west coupled thermal radiator panels and a spacecraft heat dissipation method.

SUMMARY OF THE INVENTION

[0006] To accomplish the above and other objectives, the present invention provides for a spacecraft radiator system comprising coupled east and west facing thermal radiator panels. A spacecraft is provided that has radiator panels disposed on east and west facing sides thereof. Each east and west facing radiator panel comprises a set of heat pipes. Heat dissipating equipment is mounted on the east and west panel heat pipes. Another set of heat pipes, which are preferably loop heat pipes, are used to thermally couple the heat pipes of the east and west facing radiator panels.

[0007] Typically, east and west facing panels of the spacecraft offer limited thermal dissipation capability due to the high incident solar load on those surfaces. In accordance with the present invention, the east and west facing panels may be used to mount and dissipate the thermal load caused by equipment such as RF loads, feeds, switches, circulators and multiplexers (OMUXs), which can withstand temperatures higher than normal payload electronics equipment.

[0008] In order to reduce the impact of the incident solar load, the east and west panels are thermally coupled together and thereby, share the thermal load. By coupling the east and west panels together, the thermal dissipation capability of the east and west radiator panels of the radiator system can be increased by approximately 50%. In addition, the radiator system can accommodate an imbalance in payload thermal dissipation between east and west panels, thereby reducing required heater power.

[0009] A spacecraft heat dissipation method is also provided by the present invention. The spacecraft heat dissipation method comprises the following steps.

[0010] A spacecraft is configured to have a body with north, south, east and west facing panels. One or more heat pipes are disposed on each of the east and west facing panels. Heat dissipating equipment is selectively mounted on the heat pipes on the east and west facing panel. One or more coupling heat pipes thermally interconnect the heat pipes on the east and west facing radiator panels together. The spacecraft is launched into orbit. In orbit, heat coupled to the one or more heat pipes on the east and west facing panels by the heat dissipating equipment is coupled to the one or more heat pipes of the other of the east and west facing panels.

[0011] The present invention offers significant performance advantages over U.S. Pat. No. 5,372,183, which merely radiatively couples the north, south, east and west sides of the spacecraft. The present invention utilizes heat piped radiator panels on both the east and west facing panels and loop heat pipes to thermally couple the panels together. This offers a ten-fold increase in the ability to transfer heat from the east to west sides of the spacecraft.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawing, wherein like reference numerals designate like structural elements, and in which:

[0013] FIG. 1 illustrates a spacecraft employing an exemplary spacecraft radiator system in accordance with the principles of the present invention;

[0014] FIG. 2 is a flow diagram that illustrates an exemplary spacecraft heat dissipation method 30 in accordance with the principles of the present invention.

DETAILED DESCRIPTION

[0015] Referring to the drawing figures, FIG. 1 illustrates a spacecraft 10 employing an exemplary spacecraft radiator system 20 in accordance with the principles of the present invention. The spacecraft 10 illustrated in FIG. 1 comprises a body 11 having north, south, east and west facing panels 12, 13, 14, 15. The exemplary spacecraft 10 has plurality of antennas 16 coupled to the east and west facing sides of the body 11.

[0016] In a typical spacecraft 10 the north and south facing panels 12, 13 are used as radiator panels of the radiator system 20. In accordance with the of the present invention in the present spacecraft 10 also uses the east and west facing panels 14, 15 as additional radiator panels of the radiator system 20.

[0017] The east and west facing panels 14, 15 each comprise one or more heat pipes 21. Heat dissipating equipment 22 or payload equipment 22 is mounted on the east and west panel heat pipes 21. Another set of one or more coupling heat pipes 23, which are preferably loop heat pipes 23, are used to thermally couple the heat pipes 21 of the east and west facing radiator panels 14, 15 together. The east and west panels 14, 15 thus act in tandem to dissipate heat generated by the heat dissipating equipment 22 or payload equipment 22 mounted on the east and west panel heat pipes 21.

[0018] Each of the loop heat pipes 23 comprise thin walled tubing that may be coupled between an evaporator and a condenser. The evaporator and condenser are thermally coupled to the heat pipes 21 of the east and west facing radiator panels 14, 15.

[0019] By coupling the east and west facing panels 14, 15 together in this manner, the east and west facing panels 14, 15 share the heat load. This increases the thermal dissipation capability of the east and west facing radiator panels 14, 15 and radiator system 20 by approximately 50%. This offers a ten-fold increase in the ability to transfer heat from the east to west sides of the spacecraft 10. In addition, because the east and west panels 14, 15 are coupled together, the radiator system 20 can accommodate an imbalance in payload thermal dissipation between the east and west panels 14, 15, thereby reducing required heater power.

[0020] FIG. 2 is a flow diagram that illustrates an exemplary spacecraft heat dissipation method 30 in accordance with the principles of the present invention. The exemplary spacecraft heat dissipation method 30 comprises the following steps.

[0021] A spacecraft 10 is configured 31 to have a body 11 with north, south, east and west facing panels 12, 13, 14, 15, one or more heat pipes 21 disposed on each of the east and west facing panels 14, 15, heat dissipating equipment 22 selectively mounted on the heat pipes 21 on the east and west facing panels 14, 15, and one or more coupling heat pipes 23 that thermally interconnect the heat pipes 21 on the east and west facing radiator panels 14, 15 together. The spacecraft 10 is launched 32 into orbit. In orbit, heat coupled to the one or more heat pipes 21 on the east and west facing panels 14, 15 by the heat dissipating equipment 22 is coupled 33 to the one or more heat pipes 21 of the other of the east and west facing panels 14, 15.

[0022] Thus, a spacecraft radiator system comprising east and west facing radiator panels and spacecraft heat dissipation method have been disclosed. It is to be understood that the above-described embodiments are merely illustrative of some of the many specific embodiments that represent applications of the principles of the present invention. Clearly, numerous and other arrangements can be readily devised by those skilled in the art without departing from the scope of the invention.