Simulation of Water Level Fluctuations in a Hydraulic System Using a Coupled Liquid-Gas Model

• A model for simulating vertical water level fluctuations with coupled liquid andgas phases is presented. The Preissmann implicit scheme is used to linearize the governingequations for one-dimensional transient flow for both liquid and gas phases, and the linearsystem is solved using the chasing method. Some classical cases for single liquid and gasphase transients in pipelines and networks are studied to verify that the proposed methodsare accurate and reliable. The implicit scheme is extended using a dynamic mesh tosimulate the water level fluctuations in a U-tube and an open surge tank withoutconsideration of the gas phase. Methods of coupling liquid and gas phases are presentedand used for studying the transient process and interaction between the phases, for gasphase limited in a chamber and gas phase transported in a pipeline. In particular, two othersimplified models, one neglecting the effect of the gas phase on the liquid phase and theother one coupling the liquid and gas phases asynchronously, are proposed. The numericalresults indicate that the asynchronous model performs better, and are finally applied to ahydropower station with surge tanks and air shafts to simulate the water level fluctuationsand air speed.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Strömningsmekanik och akustik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Fluid Mechanics and Acoustics (hsv//eng)

Nyckelord

gas phase

one-dimensional (1D)

coupled solution

vertical fluctuation

water level

liquid phase

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)