Skip to main content

Research Repository

Advanced Search

Thin film thickness measurements in two phase annular flows using ultrasonic pulse echo techniques

Al-Aufi, Y.A.; Hewakandamby, B.N.; Dimitrakis, G.; Holmes, M.; Hasan, Abbas; Watson, N.J.


Y.A. Al-Aufi

B.N. Hewakandamby

G. Dimitrakis

M. Holmes

N.J. Watson



The electric power generation and oil/gas production industries have a strong interest in the physical characterization of conducting and non-conducting liquid films that are formed during the flow of liquids in pipes. Conducting and non-conducting liquid films do not lend themselves to the same characterization techniques due to the different requirements originating from their electrical properties. Techniques based on the use of ultrasound are extremely attractive for that purpose as they do not depend on the electrical properties of the liquid and are also non-invasive. This paper presents the application of ultrasonic techniques for measuring the thickness of wavy thin liquid films (less than 6 mm) in vertical pipes. Initial benchtop experiments were performed, and different signal processing methods were implemented in order to identify the most suitable depending on the film thickness. For a film thickness greater than 0.5 mm a time of flight method was utilized whereas for a film thicknesses less than 0.5 mm a frequency method and time domain method were utilized. These methods were validated using a theoretical volume measurement on a static system. The studied methods were then tested on downward and upward vertical flow experimental rigs with pipe diameters of 127 mm and 34.5 mm respectively. The results of the experiments using ultrasonic methods showed good agreement with the measurements obtained using a multi pin film sensor and a concentric conductance probe, highlighting the potential that ultrasound offers in thin film measurements.


Al-Aufi, Y., Hewakandamby, B., Dimitrakis, G., Holmes, M., Hasan, A., & Watson, N. (2019). Thin film thickness measurements in two phase annular flows using ultrasonic pulse echo techniques. Flow Measurement and Instrumentation, 66, 67-78.

Journal Article Type Article
Acceptance Date Feb 16, 2019
Online Publication Date Feb 25, 2019
Publication Date 2019-04
Deposit Date Sep 16, 2019
Journal Flow Measurement and Instrumentation
Print ISSN 0955-5986
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 66
Pages 67-78
Keywords Modelling and Simulation; Instrumentation; Electrical and Electronic Engineering; Computer Science Applications
Public URL
Publisher URL
Related Public URLs