NASA Lewis Research Center, 21000 Brookpark Road, Cleveland, Ohio 44135

41 -- SHELL AND TUBE HEAT EXCHANGER SOL RFO3-029424 POC Jon Schultz, Contracting Officer, (216) 433-2764, MS 500-306. The heat exchanger shall be designed to cool 1.7 lbs/sec of liquid hydrogen flowing through tubes from 42.5 to 27.0 degrees R while immersed in a sub-atmospheric bath of 26.0 degrees R boiling hydrogen. The 1.0 R degrees difference at the exit of the heat exchanger results in a design log mean temperature difference (LMTD) of 5.5 degrees R. This very stringent LMTD requirement can only be achieved with highly efficient heat transfer surfaces. In 1991 the Superconducting Super Collider (SSC) program went out for bids for a liquid helium heat exchanger with very similar requirements. Cryogenic Technical Services Inc. (CTS) was the only company that developed a proprietary extruded aluminum heat exchanger tube with external machined fins to meet the SSC requirements. The heat exchanger supplied by CTS, under this SSC contract, met all requirements. Delivery to Plum Brook - K - Site - Sandusky, Ohio. Delivery schedule is 90 calendar days after contract award. This notice is for information only. Justification to permit contracting with Cryogenic Technical Services has been prepared using citation 10 USC 2304(c)(1) as its authority. This procurement is being conducted under the NASA MidRange Pilot Test Program approved by the Office of Federal Procurement Policy on April 16, 1993. See Numbered Note(s): 22. (0179)

Loren Data Corp. http://www.ld.com (SYN# 0426 19950629\41-0001.SOL)