相关论文: Acoustically Enhanced Boiling Heat Transfer
We analyse the ultrasound waves reflected by multiple bubbles in the linearized time-dependent acoustic model. The generated time-dependent wave field is estimated close to the bubbles. The motivation of this study comes from the therapy…
We present a general theory of thermoacoustic phenomena in supercritical fluids near the critical point in a one-dimensional cell. We take into account the effects of the heat conduction in the boundary walls and the bulk viscosity near the…
Vertical natural convection (VC), often cannot meet the high heat transfer demands due to the inherent misalignment of the direction of buoyancy (vertical) with the direction of the heat transfer (horizontal). Here we applied a novel…
The influences of blood vessels and focused location on temperature distribution during high-intensity focused ultrasound (HIFU) ablation of liver tumors is studied. A three-dimensional acoustics-thermal-fluid coupling model is employed to…
We experimentally demonstrate the dynamical tuning of the acoustic field in a surface acoustic wave (SAW) cavity defined by a periodic arrangement of metal stripes on LiNbO3 substrate. Applying a DC voltage to the ends of the metal grid…
Operating high-intensity discharge lamps in the high frequency range (20-300 kHz) provides energy-saving and cost reduction potentials. However, commercially available lamp drivers do not make use of this operating strategy because light…
Vaporization of low-boiling point droplets has numerous applications in combustion, process engineering and in recent years, in clinical medicine. However, the physical mechanisms governing the phase conversion are only partly explained.…
We present a class of sonic meta-screens for manipulating air-borne acoustic waves at ultrasonic or audible frequencies. Our screens consist of periodic arrangements of air bubbles in water or possibly embedded in a soft elastic matrix.…
Standing acoustic waves have been known to generate Eulerian time-mean 'streaming' flows at least since the seminal investigation of Lord Rayleigh in the 1880s. Nevertheless, a recent body of numerical and experimental evidence has shown…
Acoustically driven mixing of small fluid volumes is reported. Using surface acoustic waves on a mixer chip, conversion of those into bulk waves, and employing wave guiding effects enables us to distribute a set of "virtual sources" for…
The authors describe how acoustic phonons can directly tunnel through vacuum and, therefore, transmit energy and conduct heat between bodies that are separated by a vacuum gap. This effect is enabled by introducing a coupling mechanism,…
An effect we have termed the acousto-thermoelectric effect is theorized for temperature gradients driven by acoustic modulation. The effect produces a dynamic and spatially varying voltage. Adiabatic acoustic fluctuations in a solid cause…
Mist/air two-phase flow is a promising cooling technique for many applications such as internal cooling of gas turbine blades. A significant enhancement of heat transfer can be achieved with a low mass fraction of droplets by utilizing the…
This paper deals with the triggering mechanism of the boiling crisis, a transition from nucleate to film boiling. We observe the boiling crisis in pool saturated boiling experimentally at nearly critical pressure to take advantage of the…
In this paper, the energy non-conservation problem of the hybrid thermal LB phase change model is emphasized. To solve this problem, an infinite volume discrete scheme is introduced to deal with the diffusion term in the energy equation.…
Liquid coolants containing conductive nanoparticles (nanofluids) have been widely studied over the past 30 years but have seen limited adoption in real-world cooling applications. The ability of passive nanoparticles to enhance heat…
Radio Frequency (RF) power studies are in progress following the cryogenic commissioning of Cryomodule #1 (CM1) at Fermilab's Superconducting Radio Frequency (SRF) Accelerator Test Facility. These studies are complemented by the…
We study the time-domain acoustic wave propagation in the presence of a micro-bubble. This micro-bubble is characterized by a mass density and bulk modulus which are both very small as compared to the ones of the background vacuum. The goal…
Many experiments in liquid Helium, such as the optical imaging of exploding electron bubbles, which enables research on individual particles under applied conditions, involve the usage of ultrasound generated by piezoelectric transducers.…
We present a theoretical study of near-field heat transfer between two anisotropic materials separated by a small vacuum gap and maintained in a stationary non-equilibrium thermal situation. By combining standard stochastic electrodynamics…