Browsing by Author "Sharma, Prafull"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Open Access Development of gas-liquid slug flow measurement using continuous-wave Doppler ultrasound and bandpass power spectral density(MDPI, 2021-01-08) Nnabuife, Somtochukwu Godfrey; Sharma, Prafull; Aburime, Ebuwa Iyore; Long’or Lokidor, Pauline; Bello, AbdulraufThis paper addresses the issues of slug detection and characterization in air-water two-phase flow in a vertical pipeline. A novel non-invasive measurement technique using continuous-wave Doppler ultrasound (CWDU) and bandpass power spectral density (BPSD) is proposed for multiphase flow applications and compared with the more established gamma-ray densitometry measurement. In this work, analysis using time-frequency analysis of the CWDU is performed to infer the applicability of the BPSD method for observing the slug front and trailing bubbles in a multiphase flow. The CWDU used a piezo transmitter/receiver pair with an ultrasonic frequency of 500 kHz. Signal processing on the demodulated signal of Doppler frequency was done using the Butterworth bandpass filter on the power spectral density which reveals slugs from background bubbles. The experiments were carried out in the 2” vertical pipeline-riser at the process system engineering laboratory at Cranfield University. The 2-inch test facility used in this experiment is made up of a 54.8 mm internal diameter and 10.5 m high vertical riser connected to a 40 m long horizontal pipeline. Taylor bubbles were generated using a quick-closing air valve placed at the bottom of the riser underwater flow, with rates of 0.5 litres/s, 2 litres/s, and 4 litres/s. The CWDU spectrum of the measured signal along with the BPSD method is shown to describe the distinctive nature of the slugsItem Open Access A microwave cavity resonator sensor for water-in-oil measurements(Elsevier, 2018-02-02) Sharma, Prafull; Lao, Liyun; Falcone, GioiaOnline monitoring of Water-Liquid Ratio (WLR) in multiphase flow is key in petroleum production, processing and transportation. The usual practice in the field is to manually collect offline samples for laboratory analysis, which delays data availability and prevents real time intervention and optimization. A highly accurate and robust sensing method is needed for online measurements in the lower end of WLR range (0%–5%), especially for fiscal metering and custody transfer of crude oil, as well as to ensure adequate flow assurance prevention and remedial solutions. This requires a highly sensitive sensing principle along with a highly precise measurement instrument, packaged together in a sufficiently robust manner for use in the field. In this paper, a new sensing principle is proposed, based on the open-ended microwave cavity resonator and near wall surface perturbation, for non-intrusive measurement of WLR. In the proposed concept, the electromagnetic fringe field of a cylindrical cavity resonator is used to probe the liquid near the pipe wall. Two of the cylindrical cavity resonance modes, TM010 and TM011 are energized for measurements and the shift in the resonance frequency is used to estimate liquid permittivity and the WLR. Electromagnetic simulations in the microwave frequency range of 4 GHz to 7 GHz are used for proof-of-concept and sensitivity studies. A sensor prototype is fabricated and its functionality demonstrated with flowing oil-water mixtures in the WLR range of 0–5%. The frequency range of the proposed sensors is 4.4–4.6 GHz and 6.1–6.6 GHz for modes TM010 and TM011, respectively. The TM011 mode shows much higher sensitivity (41.6 MHz/WLR) than the TM010 mode (3.8 MHz/WLR). The proposed sensor consists of a 20 mm high cylinder, with a diameter of 30 mm and Poly-Ether-Ether-Ketone (PEEK) filler. The non-intrusiveness of the sensor, along with the high sensitivity in the resonance shift, makes it attractive for practical applications.Item Open Access Recent advances in water cut sensing technology : Chapter 4(IFSA Publishing, 2018-12-31) Sharma, Prafull; Yeung, HoiIntroduction: Multiphase Flow Meters (MPFM) are increasingly being used for both subsea and offshore applications. They are gaining acceptance due to the benefits they bring over test separators, production control and flow assurance to name a few. Multiphase Flow Meters commonly use the measurement of mixture density or electrical permittivity of the produced mixture for estimation of phase fractions [1]. Water cut meter is often part of multiphase flow meters for measurement of water content in the multiphase mixtures. There are standalone water cut meters utilized in the oil and gas production. In this chapter, water cut measurement technologies and methods are discussed and their gaps identified. Microwave based water cut measurement is then described in greater detail along with key academic and industrial research trends.