## THERMAL SCIENCE

International Scientific Journal

### NEW METHODS TO COPE WITH TEMPERATURE ELEVATIONS IN HEATED SEGMENTS OF FLAT PLATES COOLED BY BOUNDARY LAYER FLOW

**ABSTRACT**

This paper documents two reliable methods to cope with the rising temperature in an array of heated segments with a known overall heat load and exposed to forced convective boundary layer flow. Minimization of the hot spots (peak temperatures) in the array of heated segments constitutes the primary goal that sets the platform to develop the methods. The two proposed methods consist of: 1) Designing an array of unequal heaters so that each heater has a different size and generates heat at different rates, and 2) Distancing the unequal heaters from each other using an insulated spacing. Multi-scale design based on constructal theory is applied to estimate the optimal insulated spacing, heaters size and heat generation rates, such that the minimum hot spots temperature is achieved when subject to space constraint and fixed overall heat load. It is demonstrated that the two methods can considerably reduce the hot spot temperatures and consequently, both can be utilized with confidence in industry to achieve optimized heat transfer.

**KEYWORDS**

PAPER SUBMITTED: 2013-01-28

PAPER REVISED: 2013-09-30

PAPER ACCEPTED: 2013-11-25

PUBLISHED ONLINE: 2013-12-22

**THERMAL SCIENCE** YEAR

**2016**, VOLUME

**20**, ISSUE

**Issue 1**, PAGES [45 - 52]

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