Engine test facility upgrade improves exhaust handling efficiency Published April 24, 2014 By Raquel March Arnold Engineering Development Complex Public Affairs ARNOLD AIR FORCE BASE, Tenn. (AFNS) -- Military and commercial aircraft engine developers rely on simulated altitude testing conducted at Arnold Engineering Development Complex's, or AEDC, engine test facility, or ETF for their research and development of engine capabilities. The condition of the test facility determines the quality of the test and there is an ongoing upgrade project for two of the intercoolers that aid in handling engine exhaust in the C-Plant Exhaust System. The large intercoolers, measuring 46 feet diameter at the widest section and 62 feet long, are an important configuration for handling large volumes of engine exhaust. When a turbine engine test is conducted inside the C-Plant test cells, the engine exhaust flowing from the engine can reach temperatures of approximately 850 degrees to 3,000 degrees Fahrenheit. To create the proper conditions and pressures for a test of up to 75,000 feet altitude and an engine capable of operating at 100,000 pounds of thrust, the C-Plant Exhaust System houses coolers and compressors that cool and draw the engine exhaust. "The purpose of this project is to replace the aging cooling coils and demister pads in the WC11 and WC12 intercoolers located in the C-Plant Exhaust yard area," said Marilyn Graves, the Aerospace Testing Alliance, or ATA, program manager for the C-Plant Exhaust intercooler upgrade. "Each intercooler, or cooler, has three banks of coils, bank A, B and C, with each bank housing 20 coils for a total of 60 coils to be replaced for each cooler. "The intercoolers cool and dehumidify exhaust gas between stages of exhaust compression to improve compressor performance and efficiency and to keep the exhaust gas temperature within working limits of the equipment," she said. "The water-cooled coils currently located in coolers WC11 and WC12 have been in existence for the past 30 years. Leaks as well as damaged or sagging coils have reduced the efficiency of the coolers." Melissa Tate, the Air Force project manager for the upgrade, said the project is part of the Advanced Large Military Engine Capability Program, or ALMEC. ALMEC, an Air Force Materiel Command program, exists to improve and modernize key Air Force Aeropropulsion Test Facility systems. Planning for the project began in 2009 and involved considerations for conducting testing during the removal and installation upgrade process as well as safety in removing and handling the coils and demister pads. "There was a considerable amount of planning involved with the Intercooler Project - everything from generating specifications for the replacement coils and demister pads to laying out schedules for the installation to determine the length of an outage period needed," Graves said. "In addition, there was considerable planning regarding safety issues -- what hazards would be encountered, what PPE (personal protective equipment) would be required (and) what equipment and skill level of worker was needed." The expected completion date for the project is the summer of 2014.