We have a plan to purchase a BlueROV and other electronic components to build an underwater robot (AUV) for testing our new control law in problem of pipeline tracking. Since we do not have experience in building a such system, we are really wonder about the heat radiating from the electronic components inside watertight enclosure. Through your website and forum, I try to find the topics relating to heating treatment. However, there does not exist a such topic. My questions are:
If the AUV works continuously 1 hour, the surround water temperature is 20°, so how many degrees could be inside the enclosure? Is it "too hot"?
I heard about a liquid cooling system. Is there anyone has experience with that?
A mechanical engineer or physicist can do the analysis for you, it is relatively simple. Heat transfer through the plexiglass is easy to do, so is the heat generated by the electrical components. The difference will be the temperature rise in the enclosure. Because of the very large area on the surface of the water tight enclosure, I don’t think high temperature will be a problem for you. The batteries will be your largest generator of heat energy and that is easily computed knowing the wattage draw and battery efficiency (internal resistance). If you batteries are in a separate compartment from your electronics then that source of heat goes away. If you use the blue ESC’s that eliminates a source of heat. Hope this helps.
Actually, we are thinking of creating a separate metal compartment for all the batteries. For the main CPU of the embedded computer, we will create a frame, that will be pressed to the CPU surface for absorbing generated heat. This frame is like what you find in an ordinary laptop. I will show you all these structures after finishing design.
The electronics inside do generate quite a bit of heat, but in our experience, it is dissipated well through the enclosure. We often operate 6 ESCs in a single 4" enclosure (for the BlueROV) without any overheating issues.
@Richard - It would be very interesting to know the heat dissipation capability of the acrylic tube at different temperatures. Then you could basically have a wattage rating for heat dissipation in the tube. I’ll look into doing that.
Hello Rusty,
I came upon this old thread while researching the forum for any issues with electronics heat in the WTE and was wondering if you followed through on your ‘wattage rating’ idea for heat disipation in the WTE’s?
Thanks for reviving this! There are so many factors that contribute to how much heat can be dissipated that we don’t have ratings. For instance, the length of the tube, plastic/aluminum, end caps, and where the heat source is mounted inside all have a dramatic impact. We’ve seen people running power supplies in aluminum tubes with good connections to the tube and they can dissipate a huge amount of heat. I’d recommend testing out your application and add paths to get the heat to the tube or switch to aluminum tubes if necessary!