Heat Sink Design & Thermal Analysis

Cooler by design

48.7°C lowest modeled peak temperature

Problem

Compare passive cooling designs for a 50W COB LED streetlight dissipating 35W of heat, with an 85°C temperature limit.

My contribution & engineering decisions

I modeled rectangular, triangular, and cylindrical pin-fin geometries in SOLIDWORKS and compared steady-state temperature distributions, heat flux, and thermal gradients in ANSYS. The model used aluminum 6063-T5, 27°C ambient, and a uniform convection coefficient of 10 W/m²·°C.

Validation

I checked the simulations against extended-surface fin-theory calculations. Reported differences were 1.3–3.6%. This is an analytical comparison, not physical testing.

Outcome

Peak modeled temperatures were 48.7°C for rectangular fins, 51.77°C for triangular fins, and 52.11°C for pin fins. I recommended rectangular fins for their lowest peak temperature, 36.3°C margin below the limit, and suitability for aluminum extrusion. Their fin surface area was about 29% greater than the triangular design.

Model limits

The study assumes steady state, ideal LED-to-base contact, uniform convection, and no radiation. The triangular-fin hand calculation uses an average-thickness approximation. Contact resistance, transient behavior, and varying airflow remain future study areas.

Figures are from my Spring 2026 report, Thermal Analysis of LED Street Light Heat Sinks. Temperatures are simulation results.