Turbulence phenomenon and its potential as a renewable energy source
by Sharul Sham bin Dol
In line with its aspirations to be a more research-focused university and its commitment to fostering innovation and the intellectual growth of its graduate students and academic staff, Curtin University, Sarawak Malaysia (Curtin Sarawak) has carved yet another milestone for itself with the setting up of a Turbulence and Energy Research Laboratory.
As part of the energy and environmental research at its Faculty of Engineering and Science, work at the laboratory focuses on turbulence phenomenon and its potential as a renewable energy source as well as its effects on crude oil flow transport.
Initiated by the head of the faculty’s Petroleum Engineering Department, Associate Professor Dr. Sharul Sham bin Dol, the laboratory is being operated by six academic staff, four higher degree by research (HDR) students, an undergraduate student and a research officer forming its Advanced Fluid Mechanics Research Group.
According to Dr. Sharul, there has been interest in vortical instabilities in wakes (turbulence) since the early experiments of Strouhal in 1878. However, it was not until Kármán produced his first paper on the theory of vortex streets in 1912 that turbulence research started to grow because of its practical importance to engineers and scientists.
He added that its practicality applies to many areas such as pipeline hydrodynamics, vehicle aerodynamics, structures and building design, and meteorology application. However, despite hundreds of publications on subject, there is still little fundamental understanding of the flow.
Vortex-induced vibration (VIV) is the turbulent motion induced on a bluff body that creates irregular lift forces and results in alternating movement of the body.
In Curtin Sarawak’s Turbulence and Energy Research Laboratory, a water tunnel facility has been constructed to study the capability of VIV to generate alternative energy for offshore oil and gas platforms.
Dr. Sharul said VIV-powered systems are viable alternative sources of energy for such offshore installations as they can take advantage of low water current speeds. In order to maximise the potential for energy generation, the effects of lock in the phenomenon and different sizes of cylinder are being studied.
The research is being funded by the Malaysian Ministry of Education under its Fundamental Research Grant Scheme and Curtin Sarawak’s Research Fund Scheme.
Turbulence can also have a significant impact on oil and gas field flow transport. Crude oil has to pass through different processes before it can be refined into more useful products. Throughout all these processes, agitation will occur and lead to formation of emulsions due to turbulent kinetic energy.
Dr. Sharul said emulsion formation in pipelines will have negative effects as the presence of emulsions in crude oil will lead to different flow regimes or flow patterns, which behave dissimilar to single-phase flow. This will affect the transportation of the mixture because different flow patterns require different power inputs to pump the mixtures.
Emulsions will reduce the crude oil’s quality and occupy unnecessary volume in pipelines that could lead to economic losses. Moreover, there will be problems in the oil and water separation process with the presence of emulsions.
Higher operating costs will also be necessary to deal with the separation of emulsions from the crude oil. Furthermore, emulsions can cause corrosion in the transport system and contaminate catalysts used in the refining process.
To address these problems, the Turbulence and Energy Research Laboratory is equipped with a flow loop facility that replicates them for in-depth study. The facility focuses on the formation of emulsions in a continuous flow loop, in which emulsification is induced by constriction in pipeline and flow shear instead of using external shearing power such as stirring, shaking, blending and whisking.
This particular research work is funded by the Ministry of Education under its Exploratory Research Grant Scheme and a Collaborative Research Grant Scheme between Curtin Sarawak and PETRONAS Carigali Sdn. Bhd.
According to Dr. Sharul, other projects such as the study of aerodynamics of unmanned aerial vehicles will also be carried out using the laboratory’s wind tunnel facility.
He believes the Turbulence and Energy Research Laboratory will be a catalyst to attract more industry involvement in academic research projects and be a research hub for the university’s commercial and industrial consultancy projects in the near future.
Currently, the laboratory houses high-end research tools such as Laser Doppler Velocimeter (LDV) and Ultrasonic Velocity Profiler (UVP) for measurement purposes. Several high-performance computing machines are in the pipeline to serve its computational fluid dynamics (CFD) facilities.
Associate Professor Sharul Sham bin Dol is the Head of the Department of Petroleum Engineering, Faculty of Engineering and Science at Curtin Sarawak. He can be contacted at +60 85-443 823 or by email to sharulsham@curtin.edu.my.
