This study presents an alternative methodological approach for thermal rating of power cables installed in vertical risers covered by unvented circular protective guards. An analogue thermal-electrical circuit is proposed for the thermal analysis of cables inside vertical risers. The proposed equivalent analogue model is verified by means of indoor experiments and finite-element simulations wit...

The extreme operational environmental conditions and aging of subsea structures pose a risk to their structural integrity is critical safety. Nondestructive testing essential identify defects developing within the structure, allowing repair in timely manner mitigate against failures that cause damage environment hazard human operators. However, be cost effective, inspections must carried out wi...

In recent times, the utilisation of marine composites in tubular structures has grown popularity. These applications include composite risers and related SURF (subsea umbilicals, flowlines) units. The industry evolved development advanced composites, such as thermoplastic pipes (TCP) hybrid structures. However, there are gaps understanding its performance risers, hence need for this review on d...

This study is concerned with vortex-induced vibration (VIV) of deepwater marine risers. Riser response measurements from model tests on a densely instrumented long, flexible riser in uniform and sheared currents offer an almost ideal set-up for our work. Our objectives are two-fold: (i) we use the measured data to describe complexities inherent in riser motions accompanying VIV; and (ii) we dis...

the complete 3d nonlinear dynamic problem of extensible, flexible risers conveying fluid is considered. for describing the dynamics of the system, the newtonian derivation procedure is followed. the velocity field inside the pipe formulated using hydrostatic and bernoulli equations. the hydrodynamic effects of external fluids are taken into consideration through the nonlinear drag forces in var...

Abnormal nocturnal blood pressure (BP) dipping status may be partly determined by nocturnal sympathetic activity. We studied the effect of nighttime dosing of an alpha(1)-adrenergic blocker, doxazosin, on the BP dipping status of 118 hypertensives, all of whom underwent 24-hour ambulatory BP monitoring before and after treatment. The mean nighttime/daytime ratio of systolic BP was increased (0....

To understand the influence of collector design parameters on the flow distribution among the solar collector absorber tubes, and as a first step to any detailed analysis of the influence of flow on heat transfer in the collector and on its consequent thermal performance, this study investigates the distribution of flow through a typical system consisting of two manifolds connected by a number ...

The complete 3D nonlinear dynamic problem of extensible, flexible risers conveying fluid is considered. For describing the dynamics of the system, the Newtonian derivation procedure is followed. The velocity field inside the pipe formulated using hydrostatic and Bernoulli equations. The hydrodynamic effects of external fluids are taken into consideration through the nonlinear drag forces in var...

Long flexible cylinders (e.g. risers, tendons, mooring lines) exposed to the marine environment encounter ocean currents leading to vortex-induced vibration (VIV). These oscillations, often driven at high frequencies over extended periods of time may result in structural failure of the member due to fatigue damage accumulation. Recent developments in instrumentation and installation of data acq...