Microwave NDT for in situ monitoring of fresh/saline water fraction in natural gas flow

Hesham Enshasy, Amjad Omar, Hussein Alnuweiri, Mosong Cheng

Research output: Contribution to journalArticle


This paper proposes a microwave non-destructive testing (NDT) method to detect and estimate the volume fraction of fresh or saline water in natural gas pipelines. The gas pipe is modelled as a waveguide that is filled with gas and different quantities of static liquid water placed at the bottom of the pipe. A transceiver antenna is inserted into the pipe and the return loss is measured over a broad spectrum. It is observed that the increase in the water fraction will cause a downward shift in the resonant frequency of S11. HFSS software was used to simulate the wave characteristics for different water volume fractions (WVFs) inside the pipe and the experimental data showed that a water fraction as low as 0.2% can be quantified. The presence of saline water as opposed to fresh water causes a decrease in |S11| especially for larger than 0.4% WVFs. A curve fitting formula was developed to estimate the quantity of water from |S11| for both fresh and saline water.

Original languageEnglish
Pages (from-to)722-734
Number of pages13
JournalInternational Journal of Electronics
Issue number5
Publication statusPublished - 4 May 2017
Externally publishedYes



  • cylindrical waveguide
  • fresh water
  • gas pipe
  • NDT
  • saline water

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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