Measurement of Transient Hydraulic Pressures

Publisher Website
Google Scholar
Abstract
In experiments in which it was necessary to record transient pressure waves in water, a recording instrument was sought which possessed the following characteristics: (1) a frequency response which was the same over a range from ½ cycle to 10 kilocycles per second, (2) a continuous pressure‐time relationship in the recordings, (3) a range of sensitivity from about minus 200 pounds per square inch to several thousand pounds per square inch on the positive side, (4) the ability to be calibrated through the use of known hydrostatic pressures, and (5) relative freedom from artifacts. Several methods involving the use of piezoelectric crystals, electromagnetic pick‐ups, balanced diaphragms, high speed stoboscopic pictures of small rubber balloons, and cylindrical wire strain gauges were employed and their characteristics analyzed. Only the cylindrical wire strain gauge met all of the requirements. It consisted of a length of fine resistance wire wound on a thin‐walled, closed cylinder. The gauge operated through a bridge circuit into an amplifier and cathode‐ray oscillograph. The structure, operation, and characteristics of this gauge are considered and compared with the other methods used for recording transient hydraulic pressures.

This publication has 2 references indexed in Scilit: