Review Article
Enhancement of Heat Transfer by Ultrasound: Review and Recent Advances
Table 5
Summary of numerical researches on convection increase by ultrasound.
| Reference | Description of the study | Frequency, power, intensity | Best and/or interesting result obtained |
| Aktas et al. [81] | Shallow enclosure, vibrating vertical side wall, acoustic streaming | 20 kHz and 25 kHz | After 5 ms, at 20 kHz, ΔT = 10 K | Cai et al. [79] | Square enclosure—hot bottom, natural convection, acoustic cavitation, ultrasonic beam from the centre | 18 kHz | Field synergy principle analysis, 25% increase in at the centre | Lin and Farouk [13] | Gas-filled square enclosure vibrating side-wall, top-side heated | 20 kHz | Heat transfer enhanced with streaming flow velocity (maximum at the middle of the bottom wall) | Wan and Kuznetsov [80] | Acoustic streaming in a gap (0.1–2 mm) between two horizontal beams, the lower vibrating | 160 Hz (no ultrasound) | 1% increase in Nusselt number for constant heat flux case of the upper beam | Wan and Kuznetsov [14] | Air channel composed of two parallel beams, upper beam vibrating | 21 kHz | h from 0.9 to 82 W m−2 K−1 at constant heat flux, decreasing with channel width |
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