The growth of a vapor bubble in a superheated liquid is controlled by three factors: the inertia of the liquid, the surface tension, and the vapor pressure. As the bubble grows, evaporation takes place at the bubble boundary, and the temperature and vapor pressure in the bubble are thereby decreased. The heat inflow requirement of evaporation, however, depends on the rate of bubble growth, so that the dynamic problem is linked with a heat diffusion problem. Since the heat diffusion problem has been solved, a quantitative formulation of the dynamic problem can be given. A solution for the radius of the vapor bubble as a function of time is obtained which is valid for sufficiently large radius. This asymptotic solution covers the range of physical interest since the radius at which it becomes valid is near the lower limit of experimental observation. It shows the strong effect of heat diffusion on the rate of bubble growth. Comparison of the predicted radius‐time behavior is made with experimental observations in superheated water, and very good agreement is found.

The growth of vapor bubbles in superheated liquids. report no. 26-6

Owing to advances in micro- and nanofabrication methods over the last two decades, the degree of sophistication with which solid surfaces can be engineered today has caused a resurgence of interest in the topic of engineering surfaces for phase change heat transfer. This review aims at bridging the gap between the material sciences and heat transfer communities. It makes the argument that optimum surfaces need to address the specificities of phase change heat transfer in the way that a key matches its lock. This calls for the design and fabrication of adaptive surfaces with multiscale textures and non-uniform wettability. Among numerous challenges to meet the rising global energy demand in a sustainable manner, improving phase change heat transfer has been at the forefront of engineering research for decades. The high heat transfer rates associated with phase change heat transfer are essential to energy and industry applications; but phase change is also inherently associated with poor thermodynamic efficiency at low heat flux, and violent instabilities at high heat flux. Engineers have tried since the 1930s to fabricate solid surfaces that improve phase change heat transfer. The development of micro and nanotechnologies has made feasible the high-resolution control of surface texture and chemistry over length scales ranging from molecular levels to centimeters. This paper reviews the fabrication techniques available for metallic and silicon-based surfaces, considering sintered and polymeric coatings. The influence of such surfaces in multiphase processes of high practical interest, e.g., boiling, condensation, freezing, and the associated physical phenomena are reviewed. The case is made that while engineers are in principle able to manufacture surfaces with optimum nucleation or thermofluid transport characteristics, more theoretical and experimental efforts are needed to guide the design and cost-effective fabrication of surfaces that not only satisfy the existing technological needs, but also catalyze new discoveries.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/8A3CC28A80AFA422AB5C8266816ECF6B/S2329222914000099a.pdf/div-class-title-surface-engineering-for-phase-change-heat-transfer-a-review-div.pdf

Surface engineering for phase change heat transfer: A review

A three-dimensional twenty-seven (D3Q27) discrete velocity multiple-relaxation-time lattice Boltzmann method is developed. The proposed scheme is validated in fully developed turbulent channel, pipe and porous medium flows through direct and large eddy simulations. The direct numerical simulation of the turbulent channel flow confirms that the present scheme is as reliable as the spectrum method for simulating turbulence. Through the large eddy simulations of the pipe and porous medium flows, the present scheme shows its satisfactory accuracy for simulating turbulent flows bounded by circular walls that is failed by the three-dimensional nineteen (D3Q19) model.

A D3Q27 multiple-relaxation-time lattice Boltzmann method for turbulent flows

A new subgrid-scale (SGS) model for practical large eddy simulation (LES) is proposed. The model is constructed with the concept of mixed (or hybrid) time scale, which makes it possible to use consistent model parameters and to dispense with the distance from the wall. The model performance is tested in plane channel flows, and the results show that this model is able to account for near-wall turbulence without an explicit damping function as in the dynamic Smagorinsky model. The model is also applied to the backward-facing step flow examined by Kasagi and Matsunaga (1995) experimentally. The calculated results show good agreement with experimental data, while the results obtained using the dynamic Smagorinsky model show less accuracy and less computational stability. To confirm the validity of the present model in practical applications, the three-dimensional complex flow around a bluff body ( Ahmed, 1984 ) is also calculated with the model. The agreement between the calculated results and the experimental data is quite satisfactory. These results suggest that the present model is a refined SGS model suited for practical LES to compute flows in a complicated geometry.

A Mixed-Time-Scale SGS Model With Fixed Model-Parameters for Practical LES

Heat transfer—A review of 2003 literature

Dynamic modeling on bubble growth, detachment and heat transfer for hybrid-scheme computations of nucleate boiling

A consistent direct discretization scheme on Cartesian grids for convective and conjugate heat transfer

Large eddy simulation (LES) using a mixed-time-scale (MTS) subgrid-scale (SGS) model is applied to the intake flows in simplified internal combustion engine geometry. A modified colocated grid system is employed to obtain results as precise as possible and to perform calculations in a stable way with a central difference scheme for convective terms.The results are compared with corresponding experimental data and the Reynolds averaged Navier—Stokes (RANS) equation model results obtained using the low-Reynolds-number linear k—In addition, it is made clear that when the QUICK scheme is used in LES for the convective terms instead of the central difference scheme, the result obtained deteriorates owing to the numerical viscosity. The importance of the discretization method in practical LES is also confirmed.

Nariaki Horinouchi

Papers

Dynamic modeling on bubble growth, detachment and heat transfer for hybrid-scheme computations of nucleate boiling

A consistent direct discretization scheme on Cartesian grids for convective and conjugate heat transfer

Large eddy simulation analysis of engine steady intake flows using a mixed-time-scale subgrid-scale model

Application of a three-equation cubic eddy viscosity model to 3-D turbulent flows by the unstructured grid method

Numerical Investigation of Vehicle Aerodynamics with Overlaid Grid System