The results of ground-level tests on a 30-rolt d-c, 300-amp, blast-cooled aircraft generator are presented, air flow distribution data are given for parallel cooling passages, as determined in tests with selectively plugged passages and by probing velocity- distributions within the machine. Temperature rise data, measured with thermocouples, are given for a consid?erable number of components located in the stator and the rotor. The criti?cal component is the rotor exhaust end at full load and the commutator and brushes at part-load.nTypically, 93 percent of the machine's heat dissipation occurs by forced convection within the internal cooling passages. The temperature rise values of individual components are proportional to the flow rate raised to expo?nents between -0.7 and -1.2. These data are combined to establish an effec?tive component temperature whose rise per unit heat dissipation of the ma?chine is independent of load and a function of flow rate only.
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