The Effect of Vibration on Critical Heat Flux in a Vertical Round Tube

Abstract

The CHF generally increases with vibration intensity, which is represented by vibrational Reynolds number (Re v ); the CHF enhancement is more dependent on amplitude than on frequency. CHF enhancement seems to come from the reinforced flow turbulent mixing effect by vibration in the vicinity of heat transfer surface. Based on the experimental results, an empirical correlation is proposed for the prediction of CHF enhancement by tube vibration. The correlation predicts the CHF enhancement ratio (En) with reasonable accuracy, with an average error rate of −2.18% and 27.75% for RMS.

Enhancing radial temperature uniformity and boundary layer development in viscous Newtonian and non-Newtonian flow by transverse oscillations: A CFD study

“…Klaczak, 1997;Gündo˘gdu and C -arpinlio˘glu, 1999;Lee and Chang, 2003). However, the effects on the radial temperature distribution and the development of the thermal boundary layer in viscous fluids have not been studied.…”

On the effect of boundary vibration on mucus mobilization

“…Table 5 Base-case data for parametric study ) was always less than 30 [81]. Finally, the transient vibrational simulation was conducted over 4 periods of the cosine wave (i.e., from 𝜔𝑡 0 = 0 to 𝜔𝑡 𝑒𝑛𝑑 = 8𝜋).…”

Effect of vibrator position and frequency on heat transfer enhancement in counter flow concentric pipe heat exchanger

“…Heat transfer coefficient at tube wall is enhanced by two times under the influence of 20 kHz ultrasound (Markov et al, 1985). At atmospheric conditions, critical heat flux in vertical upward flow of tube increased with increase in vibration intensity and identified to be dependent more on amplitude compared to frequency (Lee and Chang, 2003). New correlations are presented for forced convective heat transfer of vibrating sphere, cylinder and tube to water in terms of energy dissipations from experimental data (Takahashi and Endoh, 1990).…”