We present a simple mathematical model for the fluid flow in the curtain coating process, exploiting the small aspect ratio, and examine the model in the largeReynolds-number limit of industrial interest. We show that the fluid is in free fall except for a region close to the substrate, but find that the model can not describe the turning of the curtain onto the substrate. We find that the incl...

The inclined air-curtain technology was applied to build an inclined air-curtain range hood. A draft generator was applied to affect the inclined air-curtain range hood in three directions: lateral (θ=0°), oblique (θ=45°), and front (θ=90°). The three suction flow rates provided by the inclined air-curtain range hood were 10.1, 10.9, and 12.6 m(3)/min. The laser-assisted flow visualization tech...

Reservoir siting, permitting, construction and operation can, at times, face insurmountable challenges. Mosul Dam, a multipurpose dam located in Northern Iraq, is constructed on dissolvable anhydrite, gypsum limestone formation. To mitigate long-term impacts to the foundation, designers opted for structural solution. They incorporated into design grouting gallery maintenance of foundation cutof...

The locus of ejecta excavated during an impact generates a debris curtain that expands outward. In an atmosphere this advancing curtain acts like a semipermeable barrier that displaces the surrounding as. The generated flow separates near the top of the curtain to form a vortex ring whose strong winds entrain, transport, and deposit fine-grained ejecta, affecting the morphology of distal ejecta...

In this paper, the grouting ability of sandy soils is investigated by artificial neural networks based on the results of chemical grout injection tests. In order to evaluate the soil grouting potential, experimental samples were prepared and then injected. The sand samples with three different particle sizes (medium, fine, and silty) and three relative densities (%30, %50, and %90) were injecte...

This study aims at presenting a numerical model for predicting grout flow and penetration length into the jointed rock mass using Universal Distinct Element Code (UDEC). The numerical model is validated using practical data and analytical method for grouting process. Input data for the modeling, including geomechanical parameters along with grout properties, were obtained from a case study. The...

The use of an air curtain directed across the aperture of an inclined open-ended cavity is examined as a method to reduce convective losses from a heated cavity. Computational fluid dynamics (CFD) simulations were conducted in two-dimensions for a range of air curtain velocities and axial cavity orientations. The greatest relative reduction in convective losses with an air curtain resulted when...

As an ejecta curtain advances through an atmosphere, it creates a vortex ring. By analogy with smoke rings, the curtain-driven vortex ring develops instabilities that result in waves. The number of these waves depends upon the aspect ratio of the vortex ring (i.e., the ratio of the core vortex radius to the vortex radius) and the Reynolds number (or strength) of the flow in the vortex ring. In ...

Infrared radiation is a type of electromagnetic radiation and invisible to human eyes. It is used widely in industrial, scientific, and medical applications. Pool fire is an emergent accident, which emits intense thermal radiation. In order to quantify the performance of water curtain fighting fire, a testing platform is built and experimental studies are carried out. An infrared imager is used...

In this paper, we propose a new network architecture, Network Iron Curtain that can handle network scanning attacks automatically. Network Iron Curtain does not require additional devices or complicated configurations when it detects scanning attack, and it can confuse scanning attackers by providing fake scanning results. When an attacker sends a scanning packet to a host in Network Iron Curta...