3 Replies Latest reply on Apr 28, 2015 12:21 PM by Mike Pogue

    How to setup analysis to simulate heat source effects

    Janez Novak

      Hello everyone,

       

      I'm completelly new in Solidworks.

       

      I want to simulate a temperature changes beacouse of heat source (1000 W calorifer) in garden gouse (wooden walls with one window). I already tried to setup boudary conditions. I specified window as a real wall with wall heat transfer coeficient = 6 W/m^2/K and I specified all wooden walls as ideal walls. When I simulate for 600s I get strange results. Temperature around heater is about 5000°C ??

       

      I ask, how to setup bounday conditions properly to get ok results.

      my model looks like this: http://shrani.si/f/j/pm/AyvQYp7/1.png

       

      Thanks very much for answers!

        • Re: How to setup analysis to simulate heat source effects
          Mike Pogue

          Simulation isn't going to do this very well, because it can't see the air. You may also have not bonded the heater to the walls, which would drive your temperature to infinity over time. You don't say what your outside temperature is, but that's important. Also, I don't recall whether the R value for walls includes the convection on the outside or on the inside, or whether it's just the resistance through the walls, but these are both important.

           

          This is not a good problem for Simulation. You could probably do this as an exercise in Flow Simulation, but Simulation FEA will not do anything with the internal convection which is pretty critical to your answer. Normally room temps are done with hand calcs by solving for the temperature drop through the wall that produces 1000 W (you should also include values for occupants, latent heat, any electronics etc.)

           

          Temperature drop = P/(h A)

           

          P = total power in the room (W)

          H = Average heat transfer coefficient (W/m2 K)

          A = Total wall area (m2)

           

          Add this number to the outside temp and get the inside temp and know that it's hotter near the heater than far from it. The errors are so large no matter what you do, that sophisticated analysis is not justified.