BACKGROUND AND PURPOSE Hemodynamics of cerebral vasospasm after subarachnoid hemorrhage remain unclear, and the discrepancy between ultrasonographic or angiographic evidence of arterial narrowing and neurological ischemic deficit is still debated. Most blood flow studies have been involved with large arteries, and thus, very little is known regarding the hemodynamic behavior of small perforatin...

Heat transfer coefficients were measured in a circular tube with dimpled surface. The almond type dimples were fabricated, the tube diameter (D) 19mm and dimple depth 3 mm ratio was kept constant, while holding diameter 10mm of dimple is required length 21.5mm because of the elongated shape. The Reynolds number based on the channel hydraulic diameter was varied from 25000to 95000. An experiment...

This paper presents the difference in behavior between hollow-core fiber reinforced polymer-concrete-steel (HC-FCS) columns and conventional reinforced concrete (RC) columns under vehicle collision in terms of dynamic and static forces. The HC-FCS column consisted of an outer FRP tube, an inner steel tube, and a concrete shell sandwiched between the two tubes. The steel tube was hollow inside a...

Erosion wear is a common failure form of slotted screen in service. In this paper, based on CFD software and sand production data gas field the Tarim Basin, particle velocity shear force at slot flow sieve tube were studied to determine maximum area erosion; same time, velocity, viscosity, size concentration sand-carrying fluid analyzed by orthogonal test, regression model multi-factor erosion ...

At present, there are no experimental methods that allow for the complete direction-dependent mechanical characterization of tubes. This considerably limits parameterization complex, anisotropic material models. The present study introduces a new approach to overcome these limitations: tube sections first flattened into planar geometry; then, samples uniaxial testing taken out section and used ...

Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, to provide protection from aspiration, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles, from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and c...

An experimental study on natural convection heat transfer from the outer surface of a horizontal array vertical square tubes in air is investigated. The consists three at equally different center-to-center distances. Each tube has cross-section with side length 2.00 cm, 100 cm length, and filled sand. heated by inserting an internal heating element constant flux center. Five separation distance...

A vacuum-sealed miniature X-ray tube based on a carbon nanotube field-emission electron source has been demonstrated. The diameter of the X-ray tube is 10 mm; the total length of the tube is 50 mm, and no external vacuum pump is required for the operation. The maximum tube voltage reaches up to 70 kV, and the X-ray tube generates intense X-rays with the air kerma strength of 108 Gy·cm2 min-1. I...

The corrosion damage and leakage of heat transfer tube steam generator were important factors nuclear power accident, which is closely related to the national production safety people's life property. influence size change cylindrical defect on burst pressure inconel690 alloy was studied by finite element simulation experimental measurement. According test data, relationship between parameter e...

The flow behavior around a cam shaped tube in cross flow has been investigated experimentally using flow visualization and pressure distribution measurement. The range of attack angle and Reynolds number based on an equivalent circular diameter are within 0 ≤ α ≤ 360˚ and 2 x 104 < Reeq < 3.4 x 104, respectively. The pressure drag features are clarified in relation to the flow behavior around t...