The 7-hole probe measurement system is mainly used to measure three-dimensional flow fields. During the measurement, head was in direct contact with measured object, and structure had a significant influence on accuracy of field measurement. main influencing factors were hole opening mode, position, diameter. For hemispherical perpendicular forward-facing holes, orthogonal experiments three lev...

Electrochemical machining (ECM) has been increasingly recognized for the potential for machining, while the precision of the machined profile is a concern of its application. A process to erode a hole of hundreds of micrometers on the metal surface is analyzed in the current paper. A theoretical and computational model is presented to illustrate how the machined profile evolves as the time elap...

A study has been conducted on the transmission loss of perforated plates at normal incidence. The investigation includes a theoretical analysis of the problem with validation through experimentation. The experiments comprised microphone measurements of transmission loss for 11 perforated plates with variable thickness, hole size, and porosity. The theoretical model is based on planar wave propa...

The characteristics of hole-assisted fiber (HAF) are investigated both numerically and experimentally in terms of its applicability as a bending-loss insensitive fiber (BIF). We show that HAF with the desired mode-field diameter (MFD), bending-loss and cutoff wavelength characteristics can be roughly designed by taking a few specific structural parameters into consideration. We also show that a...

Turbulent forced convective mass (heat) transfer downstream of blockages with round and elongated holes in a rectangular channel was studied. The blockages and the channel had the same 12:1 (width-to-height ratio) cross section, and a distance equal to twice the channel height separated consecutive blockages. The diameter of the holes was either 0.5 or 0.75 of the height of the channel. Naphtha...

Beam connections with reduced drilled section and slotted web have been presented after the Northridge earthquake (1994). Their new geometrical shapes have been resulted in weakening of beams and subsequently the bette rperformance of connections in the earthquakes. In this research, the advantages of both connections, mentioned above, have been studied in the Slotted Web Drilled Flange (SWDF) ...

2gkx0 + v max, where g is the universal constant of gravity, k = 0.0305 is the coefficient of friction between the ball and the ground, and vmax is the maximum velocity allowed at the border of the hole in order to make the ball to enter the hole and not to overcome it. Assuming that the ball has a diameter of 4.5cm and that the hole has a diameter of 7.5cm, vmax is equal to 110.7cm/s. At the b...

The lack of large scale structure in array maps is the result of the hole in the center of the visibility plane that arises because the smallest spacing between antennas is limited to one antenna diameter. Visibility data may be extracted for a region in the center of the hole from a single antenna map made with one array antennas. This can be accomplished by Fourier transforming the map and di...

The optimum location and diameter, of an entry hole for an intramedullary nail, in the upper proximal femur, is investigated in this article. A comparative study for five different entry hole positions and seven different hole diameters at each position, has been pursued. The entry holes were located at the tip of the trochanter, at the superior, anterior and posterior parts of the lateral neck...