## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Numerical analysis on the thermal performances of different types of fin heat sink for high-power led lamp cooling

**ABSTRACT**

The efficient cooling is very important for a light emitting diode (LED) module because both the energy efficiency and lifespan decrease significantly as the junction temperature increases. Fin heat sinks are commonly used for cooling LED modules under natural convection conditions. This work proposed two novel models of fin heat sink, named the pin-plate fin heat sink (PPF) and the oblique-plate fin heat sink (OPF), by combining plate fins with pin fins and oblique fins and their thermal performances were studied numerically. The LED module was assumed to be operated under 1 atmospheric pressure and its heat input is set to 4 watts. The PPF with 8 plate fins inside (PPF-8) and the OPF with 7 plate fins inside (OPF-7) show the best thermal performances among all PPF and OPF designs. Total thermal resistances of PPF-8 and OPF-7 decreased by 9.0% - 15.6% compared to those of three original models. And heat transfer coefficients of PPF-8 and OPF-7 were higher by 12.6% - 35.2% than those of three original heat sinks.

**KEYWORDS**

PAPER SUBMITTED: 2017-06-23

PAPER REVISED: 2017-10-31

PAPER ACCEPTED: 2017-10-31

PUBLISHED ONLINE: 2017-12-03

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