Some Operating Characteristics of a Xenon and a Xenon-Mercury, Short-Arc Lamp Immersed in Water

摘要

Two types of high-intensity, short-arc lamps were operated when immersed directly in water, and some of their underwater optical and electrical operating characteristics were measured. One lamp was filled with xenon gas and was rated at 2.2 kW dc, and the other lamp was filled with both xenon and mercury and was rated at 1 kW ac. These lamps were chosen for the very high brightness and small size of their arcs which are required for high-intensity light-beam projection in an underwater searchlight. Also, they can be flashed for signaling purposes. During the underwater operation of the lamps, the water was in direct contact with all of their outside surfaces except for the metal electrical terminals, which were insulated. The xenon lamp had the same intensity and operated at the same power level underwater as it did in air, but the xenon-mercury lamp had a 20 times lower intensity and a 50 percent lower operating power level underwater than in air. The xenon lamp was operated for approximately 100 hours in water with no visible deleterious effects of a permanent nature to the lamp. It was seen, however, that a coating built up on the lamp envelope on continued operation in saline water. Operation of the xenon lamp was accomplished in water pressures up to 380 psi (880-ft depth). The lamp was incorporated into a free-flooded underwater searchlight that has been operated successfully in various bodies of fresh and salt water. (Author)