Laboratory experimentation, numerical simulation, and energy-stability theory are used to examine the effect of interface deformation on the onset of oscillatory thermocapillary convection in half zones. Experiments are performed to map the stability boundaries marking the onset of oscillatory flow, modifying the free-surface deformation by adjusting the volume of liquid in the bridge. The stability results presented here along with those of other researchers [Monti et al., Proceedings of the 43rd Cong. Int. Artro. Fed. (1992); Hu et al., J. Cryst. Growth 142, 379 (1994)] show that free-surface curvature can have a pronounced influence on flow stability. Steady, axisymmetric flow simulations are computed using the commercial code FIDAP to model the conditions of the experiments, and reveal that flow structure near the stability boundary is sensitive to several parameters. Energy theory is applied to these simulations to determine sufficient conditions for stability. Comparisons between the theoretical and experimental results show nonconservative energy limits falling above the experimentally determined stability boundaries for bridges of various liquid volumes. While the trend of the experimental data is predicted for zones of large volume ratio (bulging zones), the same cannot be said for those with small volume ratio (necked-down zones). In addition, energy-stability limits for some undeformed-free-surface cases were determined which are above the linear-stability limits determined by other researchers, in clear contradiction of the roles of the respective theories.

Recent interest in the phenomenon of thermocapillary-induced noncoalescence and nonwetting has produced experimental evidence of the existence of a film of lubricating gas that prevents the two surfaces in question (liquid–liquid for noncoalescence; liquid–solid for nonwetting) from coming into contact with one another. Measurements further indicate that the pressure distribution in this film creates a dimpled liquid free-surface. Lubrication theory is employed to investigate the coupled effects of liquid and gas flows for a two-dimensional nonwetting case of a hot droplet pressed toward a cold wall. The analysis focuses on the respective roles of viscous and inertial forces on droplet deformation. Resultant droplet shapes show an influence of gas viscosity maintaining nonwetting and of inertia contributing to a dimple. Previous analyses of thermocapillary-driven flow in liquid layers and droplets model the gas as purely passive which cannot be the case in the present application.

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Engineering schools across the country face the growing challenge of adapting to rapidly changing technology. Computer aided engineering (CAE) software exemplifies this trend. The Mercer University School of Engineering initiated a three-year project to establish an engineering analysis center utilizing CAE resources in undergraduate education. Learning modules have been designed and implemented to enhance teaching of engineering fundamentals without compromising the depth or breadth of course material. An infrastructure of learning modules complements the general analysis thread in engineering education while imposing controlled exposure to CAE software. Learning modules expose students to state-of-the-art CAE tools without requiring a specialized CAE course. Encouraging the development of CAE skills, the project aims to facilitate and enhance undergraduate scholarship such as capstone senior design projects. This paper discusses the project strategies, concerns, plans for assessment, and some formative assessment results. The project reveals a practical means for faculty to begin developing and implementing active learning techniques.