Calculation of External Pressure from Tunnel Magazines Using AUTODYN-2D

摘要

This paper summarizes a tunnel parameter study with a commercially available hydrocode, AUTODYN-2D, run on PC's (486-33, 486-66, and Pentium). Results from straight 'shotgun' tunnels, tunnels with a chamber, and tunnels with chambers and a closure block ('KLOTZ') are compared to test data and DOD safe distance criteria. The usefulness of conducting the analysis with AUTODYN on a PC is also evaluated for ease of use, accuracy, and speed. Analytical results compared well with test data, the hydrocode was easy to use, and with software enhancements, improved hardware, and user experience the analysis speed has become adequate. A large data base from small scale and some full scale tests has been accumulated on the external pressures from detonations in tunnel magazines. This data has been used to develop very good empirical relationships for predicting external pressure as a function of the basic variables: explosive weight, chamber and tunnel volume, exit area (or hydraulic diameter) and range from the exit. However, not all tunnels conform to the basic tunnel configurations represented by most of the data. 'Hydrocodes' provide an analytical tool that should be very well suited to predicting the effects of tunnel configuration on external pressures. However, this type of code has required experienced users with access to high speed computers. Advances in software and personal computers (e.g. 486 and Pentium PC's) have made hydrocodes available to an increasing number of researchers and analysts. Although experience in use of the software will always be required, the software and computers are available for inexpensive, adequately fast, hydrocode analysis on PC's. This paper summarizes a tunnel parameter study with a commercially available hydrocode, AUTODYN- 2D, run on PC's (486-33, 486-66, and Pentium-60).