IMPROVED CERAMIC HEAT EXCHANGER MATERIAL

Various ceramic materials in the form of small, monolithic bars were screened as candidate materials in heat exchanger structures for automotive gas turbine engines. The material finally selected consists of 60 w/o* petalite (LAS) and 40 w/o of a recrystallizable glass which converts during thermal processing to cordierite (MAS). This new material, GE-3200, was fabricated by Coors Porcelain Company into a circular honeycomb structure 53.3 cm diameter and 10.2 cm thick (21'' x 4'') and having 69.8 holes/cm exp 2 (450 holes/in. exp 2 ) of rectangular geometry. Dimensions of each cell are about 2.5 mm x 0.5 mm (0.1'' x 0.02'') with wall thicknesses about 0.20 mm (0.008''). Small bar-shaped specimens of the honeycomb were used to measure thermal, chemical, and mechanical properties and for macro- and microstructure examination. Cylindrical honeycomb specimens about 15.2 cm diameter and 10.2 in. thick (6'' x 4'') were sent to Ford Motor Company and are currently being tested in a gas turbine engine. Data obtained from testing the bar-shaped honeycomb specimens of GE-3200 and from testing bar-shaped honeycomb specimens of Corning 9455 were compared. Results indicate that GE-3200 has significantly better resistance to sulfuric acid and to sodium chloride than Corning 9455; thermal expansion of GE-3200 is higher than that of Corning 9455 (1.7 x 10 exp -6 / exp 0 C vs. 0.65 x 10 exp -6 / exp 0 C over the temperature range 25 exp 0 C to 1000 exp 0 C); mechanical properties of GE-3200 are higher in the tangential direction, but lower in the radial direction than Corning 9455; and during thermal cycling between R.T. 1000 exp 0 C and R.T. -1100 exp 0 C, GE-3200 tends to elongate while Corning 9455 tends to slightly contract. Overall assessment of GE-3200 properties, ease of material preparation, ready adaptability to honeycomb fabrication, and refractoriness qualify this new material as a candidate for heat exchanger application in automotive gas turbine engines.

  • Corporate Authors:

    General Electric

    Marine Turbine & Gear Engineer, 1100 Western Ave
    Lynn, MA  United States  01910

    Department of Energy

    1000 Independence Avenue, SW
    Washington, DC  United States  20585
  • Authors:
    • Rauch, HWS
  • Publication Date: 1977-11

Media Info

  • Pagination: 36 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00181548
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: NASA-CR-135292
  • Contract Numbers: EX-76-A-31-1011
  • Files: TRIS
  • Created Date: Oct 31 1978 12:00AM