Two-phase flow induced vibrations: methodology validation. Pt.1

Multiphase flow through pipelines can result in severe pipe vibrations and fatigue damage. Commonly, finite element analyses are used to define the dynamic pipe stresses and calculate the lifetime of the piping. The fluid flow excitation forces can be estimated with analytical models or simulated in detail using computational fluid dynamics. If...

Multiphase flow induced forces for horizontal and vertical systems

Multiphase flow is a known source of vibrations in piping systems. Multiple experimental campaigns have focused on the force spectrum on horizontal bend systems. To evaluate the evolution of multiphase forces through a vertical loop, experiments have been done on an air-water, two inch pipe system consisting of four bends at near-atmospheric...

Overview of opportunities and challenges of electrical submersible pumps ESP in the geothermal energy production systems

The electrical submersible pump (ESP) is an essential and critical component in most low-enthalpy geothermal wells where high volumes of hot (up to 120°C) and harsh geothermal brine is required to be transported to the surface. Despite a great deal of knowledge and experience in the design and operation of ESP in the petroleum and water sector,...

Influence of pressure on speed of sound in oil-offloading hoses

Pressure surge or water hammer simulations are performed to evaluate a safe design or operation of oil transfer systems. The speed of sound of the transferred fluid plays a key role within pressure surge simulations. Unlike for steel pipe systems, the speed of sound in hoses is not easily determined. In industry, a value of 450 m/s is frequently...

Multiphase flow induced forces on bend structures

Multiphase conditions can lead to high vibration in flexible pipe systems due to high dynamic flow induced forces. To better model the dynamic forces, large scale 6” air-water, near-atmospheric experiments have been done with different bend radii and upstream configurations. This paper gives an overview of the obtained results with respect to...

Phase relation of forces between multiple bends

Multiphase flow induced vibrations are difficult to calculate. This is in part the prediction of the force frequency spectrum at a single bend, part the influence of bends on the multiphase flow behavior and therefore the prediction of the multiphase flow characteristics between bends. In this paper, the evolution of the forces between...

Multiphase forces on bend structures – overview of large scale 6”experiments

Piping structures are generally subjected to high dynamic loading due to multiphase forces. In particular subsea structures are very vulnerable as large flexibility is required to cope for instance with thermal stresses. The forces due to multiphase flow are characterized by a broadband spectrum with high amplitudes. These forces differ with...

Evaluating vibration performance of a subsea pump module by full-scale testing and numerical modelling

Prior to subsea installation, a subsea system has to be tested to verify whether it performs in accordance with specifications and component specific performance evaluation criteria. It is important to verify that the assembled components work in accordance with the assumptions and design criteria used in the detailed engineering. These criteria...

On the performance of the Gaia auto-collimating flat mirror assembly: Could it be even better?

The Auto-collimating Flat Mirror Assembly (AFMA) simulated the rotation of the Gaia satellite around its vertical axis. As such, it was one of the most important ground support equipment tools to test the payload performance of the Gaia mission. Although the performance of TNO's design during commissioning was excellent, one of the challenges of...

Remaining fatigue life time assessment of welded and braced side branches

High cycle fatigue failure is likely to occur when a rather undamped offshore installation is operated over a long period of time. Especially welded parts are vulnerable to fluctuating stress ranges, if the structural components, such as the small bore side branches, are loaded in resonance. In particular, the welded connections at e.g. tie-in...