## THERMAL SCIENCE

International Scientific Journal

### ANALYTICAL SOLUTION OF TRANSIENT TEMPERATURE IN CONTINUOUS WAVE END-PUMPED LASER SLAB: REDUCTION OF TEMPERATURE DISTRIBUTION AND TIME OF THERMAL RESPONSE

**ABSTRACT**

An analytical solution of transient 3-D heat equation based on integral transform method is derived. The result are compared with numerical solution, and good agreements are obtained. Minimization of response time and temperature distribution through a laser slab are tested. It is found that the increasing in the lateral convection heat transfer coefficient can significantly reduce the response time and the temperature distribution while no effect on response time is observed when changing pumping profile from Gaussian to top hat beam in spite of the latter reduce the temperature distribution, also it is found that dividing the pumping power between two slab ends might reduce the temperature distribution and it has no effect on thermal response time.

**KEYWORDS**

PAPER SUBMITTED: 2014-12-10

PAPER REVISED: 2015-11-09

PAPER ACCEPTED: 2015-11-29

PUBLISHED ONLINE: 2015-12-13

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**3**, PAGES [1223 - 1230]

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