We present the results of laboratory experiments that quantify the physical controls on the thickness of the falling film of liquid around a Taylor bubble, when liquid–gas interfacial tension can be neglected. We find that the dimensionless film thickness l′ (the ratio of the film thickness to the pipe radius) is a function only of the dimensionless parameter Nf = r √ gD3/m, where r is the liqu...

We investigate experimentally the influence of suspended particles on the transition to turbulence. The particles are monodisperse and neutrally buoyant with the liquid. The role of the particles on the transition depends upon both the pipe to particle diameter ratios and the concentration. For large pipe-to-particle diameter ratios the transition is delayed while it is lowered for small ratios...

Original scientific paper Stress measurement by using ultrasonic waves is based on acoustoelasticity law, i. e. the relation between stress and wave velocity in engineering materials. Longitudinal critically refracted (LCR) wave is a popular ultrasonic wave in the ultrasonic stress measurement application. The LCR wave is a bulk longitudinal wave that travels within an effective depth underneat...

Rehabilitation of a watermain by grouted sliplining is usually carried out when the existing pipe is only partially deteriorated. Although designs that neglect the structural contributions from the existing pipe and the grout are generally conservative, the performance of the rehabilitated pipe needs to be better understood for effective design and management of buried water pipes. Presented in...

The outlet feeder pipe thinning in a PHWR (Pressurized Heavy Water Reactor) is caused by high pressure steam flow inside the pipe, which is a well known degradation mechanism called FAC (Flow Assisted Corrosion). In order to monitor the degradation, the thickness of the outlet bends closed to the exit of the pressure tube should be measured and analyzed at every official overhaul. This paper de...

The outlet feeder pipe thinning in a PHWR (Pressurized Heavy Water Reactor) is caused by a high pressure steam flow inside the pipe, which is a well known degradation mechanism called a FAC (Flow Assisted Corrosion). In order to monitor the degradation, the thickness of the outlet bends close to the exit of the pressure tube should be measured and analyzed at every official overhaul. This paper...

Liquid Natural Gas (LNG) processing facilities contain large complex networks of pipes of varying diameter and orientation intermixed with control valves, processes and sensors. Regular inspection of these pipes for corrosion, caused by impurities in the gas processing chain, is critical for safety. Popular existing non-destructive technologies that used for corrosion inspection in LNG pipes in...

0017-9310/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.ijheatmasstransfer.2009.12.007 * Corresponding author. E-mail address: [email protected] (K. Vafai). Analytical models are utilized to investigate the thermal performance of rectangular and disk-shaped heat pipes using nanofluids. The liquid pressure, liquid velocity profile, temperature distribution of the heat pipe wall, tempera...