A novel scheme is presented for production of a thin (< 1 mm) uniform vapor layer over a large surface area (> 100 cm 2) by pulsed laser ablation of a solid surface. Instead of dispersing the laser energy uniformly over the surface, a modified Fabry-Perot interferometer is employed to concentrate the laser energy in very narrow closely-spaced concentric rings. This approach may be optimized to ...

A novel scheme is presented for production of a thin (< 1 mm) uniform vapor layer over a large surface area (> 100 cm 2) by pulsed laser ablation of a solid surface. Instead of dispersing the laser energy uniformly over the surface, a modified Fabry-Perot interferometer is employed to concentrate the laser energy in very narrow closely-spaced concentric rings. This approach may be optimized to ...

We perform computer simulations of the quasiliquid layer of ice formed at the ice-vapor interface close to the ice Ih-liquid-vapor triple point of water. Our study shows that the two distinct surfaces bounding the film behave at small wavelengths as atomically rough and independent ice-water and water-vapor interfaces. For long wavelengths, however, the two surfaces couple, large scale parallel...

This paper presents model simulation results of vapor intrusion into structures built atop sites contaminated with volatile or semi-volatile chemicals of concern. A three-dimensional finite element model was used to investigate the importance of factors that could influence vapor intrusion when the site is characterized by non-homogeneous soils. Model simulations were performed to examine how s...

This study explores the mechanism of flow boiling critical heat flux (CHF) in a 2.5 mm 5 mm horizontal channel that is heated along its bottom 2.5 mmwall. Using FC-72 as working fluid, experiments were performed with mass velocities ranging from 185–1600 kg/ms. A key objective of this study is to assess the influence of inlet vapor void on CHF. This influence is examined with the aid of high-sp...

The convective flow in a layer of volatile silicone oil confined to a sealed cavity with a transverse aspect ratio of 3.2 was visualized using particle pathlines and quantified by particle-image velocimetry at dynamic Bond numbers estimated to be of order unity and laboratory Marangoni numbers as great as 3400. The effect of noncondensables (i.e., air) was studied by comparing convection in the...

Depletion of the liquid density near a solid surface with a weak longrange fluid-surface interaction was studied by computer simulations of the liquidvapor coexistence of a LJ fluid confined in slitlike pores. In a wide temperature range the liquid density decreases towards the surface without the formation of a vapor layer between the liquid and the solid surface. This evidences the absence of...

The interfacial instabilities important to the modeling of critical heat flux (CHF) in reduced-gravity systems are sensitive to even minute body forces, especially for small coolant velocities. Understanding these effects is of paramount importance to both the reliability and safety of two-phase thermal management loops proposed for future space and planetary-based thermal systems. Unfortunatel...

Using existing heat transfer data, a relatively simple expression was developed for estimating the effective thickness of the boundary layer of air surrounding cylinders. For wind velocities from 10 to 1000 cm/second, the calculated boundary-layer thickness agreed with that determined for water vapor diffusion from a moistened cylindrical surface 2 cm in diameter. It correctly predicted the res...

Damages are created in a sacrificial layer of silicon dioxide by ion implantation to enhance the etch rate of silicon-dioxide in liquid and vapor phase hydrofluoric acid. The etch rate ratio between implanted and unimplanted silicon dioxide is more than 150 in vapor hydrofluoric acid (VHF). This feature is of interest to greatly reduce the underetch of microelectromechanical systems anchors. Ba...