LED's are more than just another type of lightbulb..!

I have been talking to a fair number of engineers in lighting companies that are currently working on implementing "LEDs" into their product designs. Definitely the new thing right now. Let's look at why...

1. They are more energy efficient (more lumens/Watt).
2. The lighting is directional, so there is no wasted light.
3. Very long lifetime- 50-100k hours.
4. Environmentally sound - no Hg, Pb etc.
5. Infinitely dimmable
6. Work great in cold environments

Above is a video of a model we did for a customer recently. The user wanted to optimize the performance by ensuring that the junction temperature stayed below a critical value. We tried a variety of options, such as, different heat sink designs, different LED arrangements and different housing configurations. Classic application for Upfront CFD. Allows us to provide an answer to the classic question, "what if?".

There are a variety of challenges for engineers that are new to the LED world. Here is a list of the challenges engineers are facing.

1. The desire to get the maximum output, so engineers are constantly pushing the limit of the LED devices.
2. There is not enough data available so the "rules of thumb" are currently being developed.
3. The data provided to engineers is not accurate from the manufacturers.
4. The testing that is being done does not replicate the actual environments in which the LEDs are being used.
5. A wide variance in the lifespan of the LEDs based on the junction temperatures.
6. Finding creative ways to manage the heat.
   
   

The overwhelming concern for engineers is to maintain the junction temperature. Check out the graph above. It shows how increasing the junction temperautre drastically reduces the lifescycle of the LED.

There is a ton of info out there on the web that goes into more specifics. Go check it out. Always fun to be able to help engineers solve some of their fundamental issues. To me, LEDs are not much different than any other product out there from a simulation perspective. But it has been interesting learning more and more about how they are being used in the world.