A frozen phase transition model is developed to investigate the heat and mass transfer of a single water droplet during the vacuum freezing process. The model is based on the diffusion-controlled evaporation mechanism and phase transition characteristics. The droplet vacuum freezing process can be divided into three stages according to the droplet states and the time order. It includes the evap...

In CI engines, the evaporation rate of fuel on various hot surfaces, including the combustion chamber, has a significant effect on deposit formation and accumulation, the exhaust emissions of PM and NOx, and their efficiency. Therefore, the evaporation of liquid fuel droplets impinging on hot surfaces has become an important subject of interest to engine designers, manufacturers, and researcher...

One would expect that the evaporation process of liquid droplets was described many years ago. On the contrary, just recently some underlying principles of the dynamic process of evaporation have been published. It seems that during the evaporation of a liquid droplet, the liquid at the edge of the droplet is ”pinned” to the underlying surface. This pinning prevents the droplet from shrinking. ...

The evaporation coefficients of water in air and nitrogen were found as a function of temperature by studying the evaporation of a pure water droplet. The droplet was levitated in an electrodynamic trap placed in a climatic chamber maintaining atmospheric pressure. Droplet radius evolution and evaporation dynamics were studied with high precision by analyzing the angle-resolved light scattering...

Molecular dynamics simulations are used to investigate the subcritical and supercritical evaporation of a Lennard-Jones (LJ) argon nanodroplet in its own vapor. Using a new technique to control both the ambient temperature and pressure, a range of conditions are considered to define a transition line between subcritical and supercritical evaporation. The evaporation is considered to be supercri...

We focus on an evaporation process of a volatile droplet on a temperature-controlled solid substrate. The process is strongly affected by suspending tiny particles inside the droplet, resulting in a well-known phenomenon called the "coffee stain problem." The target systems in this study are (1) the water-hydrophilic particle and (2) the water-ethanol mixture-hydrophilic particle. Spatio-tempor...

To perform the visual measurement of the evaporation process of a sessile droplet, a dual-channel simultaneous phase-shifting interferometry (DCSPSI) method is proposed. Based on polarization components to simultaneously generate a pair of orthogonal interferograms with the phase shifts of π/2, the real-time phase of a dynamic process can be retrieved with two-step phase-shifting algorithm. Usi...

Using a unique, near-field microscopy technique, fringe patterns and nanoparticle motions are visualized immediately following a nanofluid droplet deposition on a glass substrate in which an air bubble is entrapped. The nanofluid consists of DI-water, 0.10% Aluminum Oxide nanoparticles with an average diameter of 50 nm, and 0.0005% yellow-green polystyrene fluorescent particles of 1 μm diameter...

The evaporation of pinned, sessile droplets resting on finite thickness substrates was investigated numerically by extending the combined field approach to include the thermal properties of the substrate. By this approach, the combined effects of the underlying substrate and the evaporative cooling were characterized. The results show that the influence of the substrate on the droplet evaporati...

The evaporation coefficients of water in air and nitrogen were found as a function of temperature, by studying the evaporation of pure water droplet. The droplet was levitated in an electrodynamic trap placed in a climatic chamber maintaining atmospheric pressure. Droplet radius evolution and evaporation dynamics were studied with high precision by analyzing the angle-resolved light scattering ...