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Abstract: Detailed computational modeling is performed to study influences of support fibers on vaporizing fuel droplets. Droplets are supported on thin fibers and vaporize in high-temperature and high-pressure environments with cross flows that are perpendicular to the fiber. Droplet Reynolds numbers, based on initial droplet diameters are 0.1, 4, and 30. The temperature distribution inside a support fiber is almost one-dimensional with significant gradients being formed only along the fiber axis, leading to heat transfer along the fiber into a droplet. Strong capillary flows can be generated on the surface of a droplet because of heating from the support fiber. The capillary flows can influence droplet size histories by causing faster mixing within droplets, leading to reduced vaporization rates at early times. [Copyright &y& Elsevier]

Abstract: Numerical calculations are carried out to study flows around liquid droplets held in place by cylindrical fibers. Two configurations were considered: (1) a droplet supported at the middle of a fiber that extends into the gas phase on both sides of the droplet and (2) a droplet suspended at the end of a fiber. Calculations are done for droplet Reynolds numbers based on droplet diameters of 0–100. The flow around a supported droplet loses its axisymmetry even for very thin support fibers. Significant changes are seen in flow patterns, separation lengths, and in pressure and friction drag coefficients. Maximum separation lengths increase almost linearly with support rod diameters. Where flow separation occurs, pressure drag coefficients increase while friction drag coefficients drop almost linearly with support rod diameters. For a suspended droplet, the flows at the droplet front resemble that seen for the supported droplet on one side and a free droplet on the other side. However, in the rear of the droplet, the flow interaction between the two sides creates a highly asymmetrical wake structure. [Copyright &y& Elsevier]