Using of nanofluids and ducts with corrugated walls are both supposed to enhance heat transfer, by increasing the heat transfer fluid conductivity and the heat transfer area respectively. Use of a diverging duct with a jet at inlet section may further increase heat transfer by creating recirculation zones inside the duct. In this work two-dimensional incompressible laminar flow of a nanofluid e...

An axisymmetric jet issued from a sharp edged circular convergent nozzle has been studied experimentally in the near field at Reynolds number 5.3x104  to search the saddle shape behavior of mean velocity and the role of mean static pressure in the jet flow. Due to the vena contracta effect the centerline mean velocity of the jet increases about 4.2% of its exit value and corresponding decrease ...

the effect of a combined system of the bed suction and jet injection as a pier-scour countermeasure on the turbulent flow field is studied in a laboratory flume using an acoustic doppler velocimeter (adv). the three components of the velocities in the vertical symmetry plane in the equilibrium scour hole in front and rear of the pier under 3-jet injections and bed suction rate qs/q0 = 2%located...

one of the most concerning issues for researchers is to predict the shape and dimensions of the scour pit nearhydraulic structures such as the base of bridges, weirs, valves and stilling basins due to both financial and humanhazards induced by destruction of the structure. as the scour issue has its own complexity in relation to themultiplicity of effecting factors on it, in this study therefor...

on account of some complexities such as fluid-structure interaction and extra-large deformation problems, complete simulation of abrasive water jet cutting process is very hard. the main goal of this paper is to overcome these difficulties through comprehensive simulation in ls-dyna commercial software. for this purpose the smoothed particle hydrodynamics (sph) and arbitrary lagrangian eulerian...

A water jet machining is an industrial tool capable of cutting a wide variety of materials using a very high-pressure jet of water, or a mixture of water and an abrasive substance. This paper addresses the concept of the Intelligent knowledge base system (IKBS) for optimization of product design and manufacturing process for water jet machining in computer based concurrent engineering environme...

in this paper, the effect of penicillin g drug as a green corrosion inhibitor on mild steel in 1.0 mhydrochloric acid solution has been investigated using potentiodynamic polarization, electrochemicalimpedance spectroscopy (eis) and electrochemical noise (en) techniques. the inhibition efficiencywas found to increase with increasing inhibitor concentration. potentiodynamic polarizationmeasureme...

abstract background: transtracheal jet ventilation is an alternative ventilatory approach in airway surgery. the purpose of this study was to compare respiratory efficacy of percutaneous transtracheal with endotracheal, low frequency jet ventilation during microlaryngeal surgery. methods: ninety asa class i-ii patients aged between 16 and 70 years undergoing elective microlaryngeal surgery were...

Shift work misaligns the environment and the body's internal clock. A new study suggests that this 'social jet lag' can be remedied by a 'personalized schedule', an intervention that may help reduce circadian misalignment and pathologies in shift workers.