THE HEAT PIPE

THE HEAT PIPE IS ESSENTIALLY A CLOSED, EVACUATED CHAMBER WHOSE INSIDE WALLS ARE LINED WITH A CAPILLARY STRUCTURE, OR WICK, THAT IS SATURATED WITH A VOLATILE FLUID. THE OPERATION OF THE HEAT PIPE COMBINES VAPOR HEAT TRANSFER AND CAPILLARY ACTION. VAPOR HEAT TRANSFER IS RESPONSIBLE FOR TRANSPORTING THE HEAT ENERGY FROM THE EVAPORATOR SECTION AT ONE END OF THE PIPE TO THE CONDENSER SECTION AT THE OTHER END. CAPILLARY ACTION IS RESPONSIBLE FOR RETURNING THE CONDENSED WORKING FLUID BACK TO THE EVAPORATOR SECTION. THE VAPORIZED FLUID STORES HEAT ENERGY AT THE TEMPERATURE AT WHICH THE VAPOR WAS CREATED AND WILL RETAIN THE ENERGY AT THAT TEMPERATURE UNTIL IT MEETS A COLDER SURFACE. THIS TENDENCY TO RESIST ANY DIFFERENCE IN TEMPERATURE WITHIN THE HEAT PIPE IS RESPONSIBLE FOR THE DEVICE'S HIGH THERMAL CONDUCTANCE. THE HEAT PIPE CAN OPERATE AGAINST GRAVITY AND WITHOUT A SECOND EXTERNAL ENERGY SOURCE. DEVICES THAT OPERATE ON THE PRINCIPLE OF VAPOR HEAT TRANSFER CAN HAVE SEVERAL THOUSAND TIMES THE HEAT-TRANSFER CAPACITY OF THE BEST METALLIC CONDUCTORS. HEAT PIPES HAVE BEEN MADE TO OPERATE AT VARIOUS TEMPERATURES SPANNING THE RANGE FROM BELOW FREEZING TO OVER 3,600 F. THE POWER TRANSFERRED RANGES FROM A FEW WATTS TO MORE THAN 17,000 WATTS. THE HEAT PIPE IS A UNIQUE AND VERSATILE HEAT-TRANSFER DEVICE. ITS SPECIAL PROPERTIES ARE HIGH THERMAL CONDUCTANCE, TEMPERATURE FLATTENING, HEAT-FLUX TRANSFORMATION AND SEPARATION OF HEAT SOURCE FROM HEAT SINK.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00368733
• Supplemental Notes:
  • Vol 218, No 5, PP 38-46, 3 FIG, 7 PHOT
• Authors:
  • Eastman, G Y
• Publication Date: 1968-5

Media Info

• Serial:
  • Scientific American
  • Publisher: Scientific American Incorporated
  • ISSN: 0036-8733

Subject/Index Terms

• TRT Terms: Atmospheric temperature; Capillaries; Electric power supply; Fluids; Gravity; Heat flow; Heat pipes; Heat sinks; Heat transfer; Thermal conductivity; Volatility; Volatilization
• Old TRIS Terms: Condensers /liquefiers/; Temperature inversions; Wicks
• Subject Areas: Energy; Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00216390
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 18 1994 12:00AM