## THERMAL SCIENCE

International Scientific Journal

### TRANSIENT ANALYTICAL SOLUTION OF TEMPERATURE DISTRIBUTION AND FRACTURE LIMITS IN PULSED SOLID-STATE LASER ROD

**ABSTRACT**

The exact analytical solution of axis-symmetry transient temperature and Tresca failure stress in pulsed mode solid-state laser rod is derived using integral transform method. The result obtained from this work is compared with previously published data and good agreement is found. The effect of increasing period is studied, and it is found that at constant pulse width as the period is increased, the allowable pumping power is increased too. Furthermore, the effect of changing pulse width with a constant period is studied, and it is found that as the pulse width is increased, the allowable pumping power is decreased. The effect of duty cycle is studied also and it is found that as duty cycle is increased the allowable pumping power is decreased. This work permits proper selection of pulse width, period and duty cycle to avoid laser rod fracture while obtaining maximum output laser power in the designing of laser system.

**KEYWORDS**

PAPER SUBMITTED: 2014-10-11

PAPER REVISED: 2015-03-20

PAPER ACCEPTED: 2015-03-29

PUBLISHED ONLINE: 2015-07-03

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**3**, PAGES [1213 - 1222]

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