INTRODUCTION ILLUSTRATIONS CHAPTER I 1.1 1.2 1.3 COALESCENCE OF DISTILLED WATER DROPS Introduction Experimental Methods Experimental Results a) Dimple stability of water drops b) Effects of relative humidity and Impact velocity on coalescence c) Interference patterns for colliding water ii iii vii 1 1 2 6 6 drops 8 d) Retardation of water drop evaporation 13 e) Electrical effects on dimpling 14...

Abstract—We report in this paper the evolution of a physically based drop size distribution coupling the Maximum Entropy Formalism and the Monte Carlo method to solve the coagulation equation. Using the discrete or continuous population balance equation, the Mass Flow Algorithm is formulated taking into account interactions between droplets via coalescence. After proposing a kernel for coalesce...

We develop a method for maximum-likelihood estimation of coalescence times in genealogical trees, based on population genetics data. For this purpose, a Viterbi-type algorithm is constructed to maximize the joint likelihood of the coalescence times. Marginal confidence intervals for the coalescence times based on the profile likelihoods are also computed. Our method of finding MLEs and calculat...

This Letter reports experimental results for partial coalescence when a drop merges with an interface. We find an intermediate range of drop sizes in which the merger is not complete but a daughter drop is left behind. This phenomenon is governed primarily by inertia and interfacial tension, and three regimes can be further delineated depending on the roles of viscosity and gravity. Scaling rel...

Results on bubble coalescences from the space experiment of thermocapillary bubble migration conducted on board the Chinese 22nd recoverable satellite are presented in this paper. Some coalescences of large spherical bubbles under microgravity are observed through bubbles staying at the upper side of the test cell. The data of bubble coalescence time are recorded and compared with theoretical p...

The size dependence of the drop coalescence frequency is investigated by measurement of transient drop size distributions in purely coalescing systems (with negligible drop break-up). A twopronged approach is employed to estimate the bivariate coalescence frequency function, using such experimental data. First, coalescence frequency expressions derived from mechanistic models of the relative mo...

The ability to merge two droplets is an important component of droplet-based lab-on-a-chip devices, yet flow-induced coalescence is difficult to achieve due to long film drainage times compared with relatively short residence times. We examine droplet collisions at a simple microfluidic T-junction and characterize the response for a wide range of droplet sizes and speeds. We find that three pri...