Engineered solution provides low-temperature application for ATK and NASA

Aggreko, which deals in rental power, cooling, heating and oil-free compressed air, announced that it is working with Alliant Techsystems (ATK) to test Development Motor-2 (DM-2), NASA’s second fully-developed Ares five-segment solid rocket motor. Aggreko’s low temperature chillers were used to execute the DM-2 ‘cold motor’ test – supporting ATK’s objective to meet NASA’s specification to cool the motor to 40°F to measure solid rocket motor performance at low temperature and verify design requirements of new materials, the announcement added.

According to Aggreko,the temperature of DM-2 was controlled by the atmospheric conditions within the removable building housing, the test motor. It explained that to achieve this scope of work in a controlled and repeatable manner, Aggreko process engineers and temperature control experts used specialised temporary utility equipment to cool the structure to target temperatures of 20°F. It added that its engineered solution for the cold motor test consisted of temporary generators to power the system of low-temperature chillers; specially designed low-temperature air handlers; a customised air conditioning duct system; and a suite of temperature control and electrical distribution equipment.

Describing the operation, Aggreko claimed that it designed a first-of-its-kind low-temperature air handler configuration to manage climate control for the mobile building – three stacks of two air handler units with a custom-made defrost unit. One of the air handlers drew air from inside the building, cooled it to 20°F, then recycled it into the building, while the remaining unit was on standby or defrost mode, enabling continuous cooling of air, Aggreko explained. A seventh air handler was installed to provide fresh air and positively pressurise the mobile building to eliminate infiltration of warm, moist air.

Aggreko said that prior to the live test, it detached the equipment from the building, and the structure was rolled away, and that it continued to cool the rocket motor section joints with a custom air conditioning duct system up to an hour before the rocket was fired.

“This project was unique due to its many special requirements,” said Steven Bukoski, Project manager for Aggreko Process Services, a process engineering group within Aggreko. “Aggreko’s specialised, large-capacity portable equipment and skilled technicians were critical factors in successfully achieving freezing temperatures under challenging environmental conditions, such as hot summer temperatures, cooling 1.6 million pounds of propellant, and working with a movable structure.”

“Reliable equipment and working closely with ATK on all critical issues enabled our team to meet NASA’s temperature cooling requirement and support this important milestone for NASA’s space flight programme,” he added.