Physiological Efficacy of a Lightweight Ambient Air Cooling Unit for VariousApplications

摘要

In an attempt to further advance intermittent conditioned air cooling (IC)concept, a strategy of supplementing continuous air cooling (CC) was conceived. With this approach, ambient air cooling (AC) is added during work with conditioned air cooling delivered during rest periods. A compact, battery-powered beltpack cooling unit (8.5 lb), designed and fabricated at the USAF Armstrong Laboratory, was used to deliver 12 cfm filtered ambient air during work cycles: 10 cfm to the body and 2 cfm to the face. Five experimental trials were completed in a thermally controlled chamber under warm conditions (32 deg C, 40% RH) consisting of no cooling (NC), IC, and CC during intermittent exercise, as well as NC and AC during continuous exercise. This study suggests that ambient air delivered during work by a lightweight portable unit can be applied in conjunction with conditioned air during rest to further improve personal comfort, reduce skin temperature, and decrease the cumulative fatigue seen over repeated work/rest cycles in selected military and industrial applications. Personal cooling, Heat stress, Microclimate cooling, Work/rest cycle.