6 Replies Latest reply on May 18, 2009 9:28 AM by 1-HVOYZP

    External flow study...temperature problem!!


      Hello there!

      I recently started using Flow Simulation, so I ask a little patience with my questions !!!!

      I am studying the effect of temperature on the material of an equipment of light outside. equipment that uses 30 LEDs for a total of 10W. My problem is that I get the values of the temperature near 400 ° C, which is impossible to reach with a heat source so low.
      What can I be doing wrong ...??!

      Thanks for all your help.
      Best Regards, João Amaral.
        • External flow study...temperature problem!!
          Bill McEachern
          You cna defintely get that hot if you don't have anywhere for the energy to go. In the wizard set up you should use a default wall condition that convects the heat away in accordance with your situation or do an external analysis in a natural convection enviroment.
          • External flow study...temperature problem!!
            i've choosed the external simulation, so no lids are used. But it reminds me something: when we are in a external simulation, the external fluid it's the one we define in the wizard right??! like this: i have a product assembley and i run the wizard, so at some point we have to choose the fluid...i choose air!! so i think, this is the default fluid that the calculations use to the study, right?! if i don't indicate another one. it assumes air the study. Am i correct??!
            • External flow study...temperature problem!!
              David Paulson
              Joao,

              When I responded previously, I didn't give you a complete explanation. My flow model was internal, but i wanted to plot the temperature on the containing vessel due to ambient conditions. I used a "Fluid Subdomain" to simulate the ambient condition. In this case I assigned lids to the fluid subdomain and input a very low air flow rate across the vessel.

              This might work for you if you haven't already found another workaround. I've attached a picture showing the flow simulation aw well as the Fluid Subdomain flow.
              • External flow study...temperature problem!!
                Hi David.

                Yes, i think that could be a solution...i'll try it and see the results!!
                Thanks for all the help.

                Best regards,