Schematic of the aerosol shock tube facility.
Lightsheet image of aerosol inside the test section after closing the endwall valves. . Average deviation from mean pixel RMS.
Comparison of the size distributions determined by the Malvern particle sizer and the five-color extinction diagnostic. The measurements were made on unshocked water aerosols created using an ultrasonic atomizer in argon bathgas. Note that the Malvern calculates volume-based distributions. In number space, the best-fit lognormal size distribution to the Malvern data is , , while the extinction diagnostic distribution is equivalent to , .
Schematic of the aerosol particle sizing diagnostic.
Schematic of the model showing shock-fixed coordinate system.
Comparison of two models. Author’s model: solid lines; Rudinger’s model: markers. Computed for glass spheres in air, , , shock . Glass particles account for of the mass in the system. and refer to the gas and particle temperatures, while is the stagnation temperature of the gas.
A comparison of experimental extinction data at with the two runs of the model for a water aerosol in argon. The conditions are: , , , , , and . Immediately behind the shock, the gas properties are: , . Note that the figure shows only the extinction from one color for clarity, though five colors were used to determine the initial size distribution.
Calculated diameter rate change for water droplets behind shock waves for the continuum and noncontinuum models. Initial pressure , , , . The spikes in this plot are a result of the transient behavior immediately behind the shock wave when the droplets have not yet reached their quasi-steady-state temperature. Each spike corresponds to one particle size in the discretized distribution, and following that line as it progresses to the left indicates its time history. The dash-dotted line traces out the behavior of one particle size class for clarity. Point A: Immediately behind the shock . Point B: steady-state condition, (particle time) after shock.
Diameter rate change for water droplets behind shock waves. The solid lines are the continuum calculations while the markers correspond to points taken from the noncontinuum calculations and normalized by the function given in Eq. (8). Case A: , . Case B: , . Case C: , .
Summary of shock-induced evaporation literature. DOP is di-octyl phthalate, and DIDP is di-isodecyl phthalate.
Effect of the Knudsen number on total evaporation time for water droplets where and .
Article metrics loading...
Full text loading...