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Sturtevant, B.

Publications and source records attributed to Sturtevant, B..

Performance data of the new free-piston shock tunnel T5 at GALCIT

A new free piston shock tunnel has been constructed at the Graduate Aeronautical Laboratories at Caltec. Compression tube length is 30 m and diameter 300 mm. Shock tube length is 12 m and diameter 90 mm. Piston mass is 150 kg and maximum diaphragm burst pressure is 130 MPa. Special features of this facility are that the pressure in the driver gas is monitored throughout the compression process until well after diaphragm rupture, and that the diaphragm burst pressure can be measured dynamically. An analysis of initial performance data including transient behavior of the flow over models is presented.

Hornung, H.

Gasdynamics and shock dynamics of weak shock waves

Experiments in weak-shock dynamics were conducted using a 17-in. diameter shock tube. Weak shocks were generated in air by a compressed nitrogen driver gas; the incident shock waves were brought to a focus by reflecting them from concave cylindrical reflectors at the endwall of the tube. It was found that the behavior of a shock discontinuity at a focus is determined by nonlinear gasdynamic processes. Consideration is also given to nonlinear resonance phenomena, i.e., phenomena associated with oscillatory motion in ducts, with amplitude so large that weak shocks occur. Attention is given to nonlinear resonance in open and closed tubes and to thermal and relaxation effects.

Sturtevant, B.

Nonlinear gas oscillations in pipes. II - Experiment

The problem of forced acoustic oscillations in a pipe was experimentally investigated, taking into account the response of both open and closed tubes to near-resonant excitation by large amplitude oscillations of a piston at one end of the tube. Attention was given to the effect of the orifice area on shock waves. By comparing the experimental results with nonlinear theory, wave reflection coefficients of the orifice plates were determined at both closed-tube and open-tube resonant frequencies. This approach can even be used when the terminating elements are subjected to intense periodic pressure pulses.

Sturtevant, B.

Intermolecular potentials from shock structure experiments

Ground-state intermolecular interaction potentials determined from shock structure experiments with four monatomic gases are reported. These potentials are assessed for self-consistency, using the law of corresponding states, and their suitability for engineering applications in rarefied gas dynamics is discussed.

Sturtevant, B.

Studies of shock focusing and nonlinear resonance in shock tubes

Some current problems in noise pollution which involve the dynamics of weak shock waves can be succesfully investigated using shock tubes and shock-tube techniques. Two examples presently under study are discussed; in one case the experiments are carried out in a large, conventional shock tube originally designed for studies of rarefied gasdynamics, while in the other case the experimental facility is a less conventional 'repeating' shock tube.

Sturtevant, B.