  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.
