Temperature Profiles in the Davidson Laboratory Towing Tanks

摘要

The results of a series of measurements of the temperature profile in two Davidson Laboratory towing tanks and in a Davidson Laboratory wave channel, taken with a thermistor temperature sensor, are presented. The temperature profiles were found, in general, to have up to three distinct regions, each characterized by a different temperature gradient. The surface region is about 5 in. deep and displays a great variability with time, presumably due to varying temperature and air-flow conditions in the room. The intermediate region is 30 to 40 in. thick; its temperature gradient varies considerably from values of the order of 0.001C/in., in the winter or under well-mixed conditions following high-speed testing of large models, to 0.1C/in. in the summer. The bottom region, usually about 1 ft thick in a 4.5 ft deep tank, has a time-independent constant temperature gradient of the order of 0.1C/inch. This region is undisturbed by most of the tank testing. It is maintained at the low temperature because of a constant inflow of cold dense water normally established to assist in keeping the water clean. (Author)