Three devices for treating contaminated water using a cavitating vortex have been developed and tested. The first device uses stationary twin volute casings to generate cavitating vortices. Observation of the collisions among the opposing counter-rotating vortices revealed that their end portions whirl, that the vortices never collide head-on, and that they eventually separate into several smal...

a good knowledge of the parameters causing casing damage is critically important due to vital role of casing during the life of a well. cement sheath, which fills in the gap between the casing and wellbore wall, has a profound effect on the resistance of the casing against applied loads. most of the empirical equations proposed to estimate the collapse resistance of casing ignore the effects of...

4 large hameter casing design was adopted for 34 vells drilled in the Philippines using 13-3/8” mduction casing in combination with 9-5/8’ slotted iner to improve well output and to reduce space equirement in collaring the wells. Well test results ndicate an increase in production by as much as !50% compared with wells using the usual string ambination of 9-5/8” and 7-518”. In the 600 MWe q t e...

Steam Turbines are devices used to convert thermal energy of steam into mechanical energy, which may be used to produce Electrical Energy. Steam turbine generator units are being used extensively all over the world for generation of electric power and for co-generation of steam and power. Contact pressure and pretension in bolts-analysis has been made easier in recent years due to the availabil...

Centrifugal compressors are widely used in many industrial applications because of their advantages. However, these turbomachines suffer at a low-flow rate from instabilities, such as rotating stall and surge. That leads to operational failure, pressure fluctuations vibrations the thorough system. Many mechanical solutions minimize instabilities expand operating range towards rates like active ...

It is planned to install a front monitor impulse radar on the surface of the rotating drill of tunnelling machines in order to detect obstacles such as casing pipes of vertical borings. The conventional aperture synthesis technique can no more be applied to such cases because the radar image of a pipe does not constitute a hyperbola as is the case for linear scanning radars. We have developed a...

The low-frequency tube wave speed is given explicitly for a variety of borehole nvironments. The presence of a logging tool, the effects of casing, and bore eccentricity are considered. The results are all relatively simple and indicate that the speed ecreases in the presence of a tool or borehole ccentricity. The speed increases in the presence of casing as long as the casing shear modulus exc...

The internal pressure strength of tubing and casing often cannot satisfy the design requirements in high pressure, high temperature and high H2S gas wells. Also, the practical safety coefficient of some wells is lower than the design standard according to the current API 5C3 standard, which brings some perplexity to the design. The ISO 10400: 2007 provides the model which can calculate the burs...

In this paper, the effect of an active flow control system on onset mechanisms rotating stall in axial compressor is experimentally investigated. A particular emphasis thus given patterns present tip region right before and how they evolve when applied. The involved during formation without are carefully assessed compared to literature. To purpose, development first instability into discussed b...