National Aeronautics and Space Administration

Exhausters

The exhaust system served two roles: reducing the density of the air in the test chambers to simulate high altitudes and removing hot gases exhausted by the engines being tested. This was accomplished by large exhauster equipment in the Equipment Building. When an engine was being tested it expelled extremely hot exhaust gasses. Coolers were used to reduce the temperature of these gases before they reached the exhauster equipment. The coolers required a large quantity of water and a cooling tower.

Control Panel

Large Roots-Connersville exhausters in the Equipment Building were used to pump the air and engine exhaust gases out of the PSL system. The original configuration could exhaust the 3500 °F gases at a rate of 100 pounds per second when the simulated altitude was 50,000 feet. Each of the thirteen 5100-horsepower exhauster units contained two J33 compressor wheels that could be adapted to work in tandem to drive and parallel. To control the power load, the number of units used could be varied.

In 1955 a fourth line of exhausters was added. There were three centrifugal exhausters capable of supplying 166 pounds of air per second at the test chamber altitude of 50,000 feet or 384 pounds per second at 32,000 feet. These exhausters had two first stage castings driven by a 10,000-horsepower motor; one second; one third; and one fourth stage casting driven by a 16,500-horsepower motor. The total inlet volume of the exhausters is 1,650,000 cubic feet of gas per minute. The exhausters were continually improved and upgraded over the years.

Equipment Operator

Inspecting Impeller

New Exhausters

Primary cooler

The extremely hot temperature of the engine’s exhaust had to be cooled before the air reached the exhauster equipment. As the air flow exited through the 12-foot-diameter and 37-foot-long exhaust section of the test chamber it entered into the giant primary cooler. Narrow fins or vanes inside the cooler were filled with water. As the air flow passed through the vanes, its heat was transferred to the cooling water. The cooling water was cycled out of the system, carrying with it much of the exhaust heat. Each test chamber had its own primary cooler.

The air flow was then pumped through a secondary cooler that further reduced the temperature. This secondary cooler or spray cooler cooled and scrubbed the exhaust gases to reduce explosion hazards for both test chambers. The air was then pumped through the exhausters in the Equipment Building and expelled out into the atmosphere.

Secondary Cooler

Cooler in 2008

Interior of Cooler

De-areators

A water system supplied the primary and secondary coolers and cooled the exhaust ducts and valves from the hot engine exhaust. The water circulated through a closed-loop system with make-up water added.

A cooling tower was used to dissipate the remainder of the heat from the circulating water before recycling it back to the facility. The cooling tower had several large pumps, three water softening units, and a settling basin. The softeners were used to prevent scale and corrosion in the pipes.

Cooling Tower

Pump House

Aerial View