We present the results of a combined experimental and theoretical study of drop coalescence in the presence of an initial temperature difference 1T0 between a drop and a bath of the same liquid. We characterize experimentally the dependence of the residence time before coalescence on 1T0 for silicone oils with different viscosities. Delayed coalescence arises above a critical temperature differ...

In this study, the coalescence time between two contacting sub-resonance size bubbles was measured experimentally under an acoustic pressure ranging from 10kPa to 120kPa, driven at a frequency of 22.4kHz. The coalescence time obtained under sonication was much longer compared to that calculated by the film drainage theory for a free bubble surface without surfactants. It was found that under th...

Coalescing random walks is a fundamental stochastic process, where a set of particles perform independent discrete-time random walks on an undirected graph. Whenever two or more particles meet at a given node, they merge and continue as a single random walk. The coalescence time is defined as the expected time until only one particle remains, starting from one particle at every node. Despite re...

A bubble coalescence model is developed using an Euler–Lagrangian approach for unstructured grids. The Eulerian carrier fluid is solved using large-eddy simulation (LES) and the Lagrangian particle motion is solved with equations relating the turbulent motion of the carrier fluid to forces on each discrete bubble. The collision process is deterministic; bubble–bubble collisions are assumed to b...

Coalescence of liquid drops is critical in many phenomena such as emulsion stability, inkjet printing, and coating applications. For sessile drops on a solid surface, the coalescence process is more complicated than the coalescence of drops suspended in a fluid medium as a result of the coupling of the contact line motions to the fluid flow. In this paper, we use video microscopy to track the e...

To explain the long-term persistence of polymorphic alleles (trans-specific polymorphism) at the major histocompatibility complex (MHC) loci in rodents and primates, a computer simulation study was conducted about the coalescence time of different alleles sampled under various forms of selection. At the same time, average heterozygosity, the number of alleles in a sample, and the rate of codon ...

Coalescence frequency and lifetimes of thin aqueous films formed between nitrogen bubbles were measured in dilute solutions of sodium lauryl suitate, «-amyl alcohol, and 1-butanol. The bubble pairs were formed on two adjacent capillary tubes by use of a microprocessor-controlled stepping motor, and the coalescence time was determined by an optical sensing method. For low-molecular weight alcoho...

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...

In this work has been proposed a numerical scheme with the aim of simulate the coalescence process between water drops immersed in a continuous phase (n-heptane). This numerical scheme is based in the Finite Volume method and two different values for the initial velocity of the drops were chosen. Depending of the initial velocity of collision some scenarios emerge, such as: permanent coalescenc...

This manuscript analyzes the dynamics of coalescence of an incoming aqueous plug with a wetting layer above a hydrophilic surface in the chemistrode. The chemistrode is a recently described (Chen, D.; Du, W.; Liu, Y.; Liu, W.; Kuznetsov, A.; Mendez, F. E.; Philipson, L. H.; Ismagilov, R. F. Proc. Natl. Acad. Sci. U.S.A. 2008, 105, 16843-16848) microfluidic analogue of an electrode, but operatin...