Parameters and operating conditions (a stability map) were determined for which a specific slip-joint design did not cause self-excited lateral vibration of the two cantilevered, telescoping tubes forming the joint. The joint design featured a localized annular constriction. Flowrate, modal damping, tube engagement length, and eccentric positioning were among the parameters tested. Interestingly, all self-excited vibrations could be avoided by following a simple design rule: place constrictions only at the downstream end of the annular region between the tubes. Also, overall modal damping decreased with increased flowrate, at least initially, for upstream constrictions while the damping increased for downstream constrictions.

The mathematical software effort bridges the gap between the discovery of numerical algorithms and the consumption of numerical software. The spectrum of activities is surprisingly wide, including tasks often associated with numerical analysis, program design and testing, programming practices, language standards, documentation standards, software organization, distribution methods, and even the specification of arithmetic engines. This paper highlights the most important accomplishments in the field over the last twenty years. It also examines current problems and future challenges posed by the rapid advance of technology.

Quarterly report on activities of Argonne National Laboratory's Nuclear Technical Programs, including studies on nuclear fuels and nuclear waste.