Spectral analysis of pressure drop fluctuations during flow boiling in a microchannel using FFT
Samia SADAF, Abdul HANAN, Abd Alrhman SALAMA
Abstract. This study investigates the dynamic characteristics of pressure drop fluctuations during flow boiling of water through a microchannel using numerical simulation and frequency-domain analysis. Transient pressure data was obtained from simulation of a heated microchannel under constant sidewalls temperature on ANSYS Fluent with static pressure monitored in flow domain. The time-domain signal revealed distinct oscillation patterns associated with successive flow regime transitions, including bubbly, slug, and annular flows. Fast Fourier Transform (FFT) analysis was applied to pressure data using MATLAB to quantify the dominant oscillation frequencies in the pressure drop signal. The spectral results indicated a dominated frequency peak of approximately 10 Hz which corresponded to the estimated slug/bubble passage frequency derived from the time-domain profile. The results demonstrated that frequency-domain analysis provides a quantitative means to characterize microscale boiling dynamics, revealing the relationship between pressure fluctuations, bubble dynamics and flow regime transitions.
Keywords
Flow Boiling, Microchannel, Pressure Drop, Mass Flux, CFD, ANSYS Fluent
Published online 6/20/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Samia SADAF, Abdul HANAN, Abd Alrhman SALAMA, Spectral analysis of pressure drop fluctuations during flow boiling in a microchannel using FFT, Materials Research Proceedings, Vol. 67, pp 68-75, 2026
DOI: https://doi.org/10.21741/9781644904176-10
The article was published as article 10 of the book Climate Action and Sustainability
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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