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arXiv · 1411.1255

On the flow and thermal characteristics of high Reynolds numbers (2800-17000) dye cell: simulation and experiment

G. K. Mishra·Abhay Kumar·O. Prakash·R. Biswal·S. K. Dixit·S. V. Nakhe
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Abstract

This paper presents computational and experimental studies on wavelength/frequency fluctuation characteristics of high pulse repetition rate (PRR: 18 kHz) dye laser pumped by frequency doubled Nd:YAG laser (532 nm). The temperature gradient in the dye solution is found to be responsible for wavelength fluctuations of the dye laser at low flow rates (2800<Red<5600). The turbulence Reynolds number (ReT) and the range of eddy sizes present in the turbulent flow are found to be responsible for the fluctuations at high flow rates (8400<Red<17000). A new dimensionless parameter, dimensionless eddy size (l_plus), has been defined to correlate the range of eddy sizes with the experimentally observed wavelength fluctuations. It was found that fluctuations can be controlled by keeping ReT~10 and l_plus max~1. The simulated result explains the experimental observation and provides a basis for designing the dye cells for high PRR pumping.

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G. K. Mishra, Abhay Kumar, O. Prakash, R. Biswal, S. K. Dixit, S. V. Nakhe. 2014-11-05. On the flow and thermal characteristics of high Reynolds numbers (2800-17000) dye cell: simulation and experiment. https://doi.org/10.1364/ao.54.003106

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