Source Development for an Array to Generate Underwater Rectangular Pulses.

摘要

SRI International is assisting the Defense Nuclear Agency (DNA) and the Underwater Explosion Research Division (UERD) in developing a technique for generating a plane wave in water to simulate the pulse generated by an underwater nuclear explosion. The technique is being developed to improve the current method of loading submarine sections in which the energy source is concentrated as a large sphere or as a single line of explosive. The technique design consists of a vertical square array of equally spaced point sources. Each source is a compact coil of Primacord explosive wound on a simple cylindrical mandrel; the coil axes are horizontal and perpendicular to the array plane. Simple exploratory tests at SRI with single small-scale coils of mild detonating fuze and a full-scale test at UERD with a Primacord coil produced pulses that superposed to predict a satisfactory array pulse, apart from an excessive rise time. An approximate analysis was performed that provided a simple formula for the array pulse resulting from specified point source pulses. The principal result is that the array pulse rise time is about the same as the characteristic time of the source pulse. This result suggested that the array pulse rise time will be decreased if the linear density of the explosive strand forming the coil is decreased substantially over the final two-thirds of its length.