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sun vector position and ambient temperature in the domain

    • ansys beginner
      Subscriber

      Hi,

      I am beginner in Ansys s at the moment struggling with things that can reults easy for other but I have two issues:

      1- After running a 24 timesteps (1 day) solar load calculation (only activated solar ray tracing/fear weather condition) of a stand-alone buiding in ansys (image "1"),

       I want to get for each time step of my simulation (i.e. for the facade south of the builfing) (unique value in each timestep) : the sun vector postion, ambient temperature (or ambeint temperature inside my domain), and the contribution of beam, diffuse and ground reflected radiation in "Solar heat flux" (imafe "3") as outputs of my simulation to understand how solar ray tracing works.

       

      How can I do it? what are exactly the steps I need to follow?

      2- When I want to add a model such as SFS and DO, run the simulation and compare the heat flux values for each building facade and contour heat flux distribution across the façade (image 2)

       

      i get the same values of heat flux and countour figure for each timestep (not all time steps exactly the same value unless at 1 pm for case 1, 2 and 3 for example: 134 Wm-2, at 4 pm for case 1, 2 and 3: 88 Wm-2 and so on) for all three cases with no difference

      case 1- only solar ray tracing

      2- solar ray tracing + DO

      3- solar ray tracing + S2S

      i expected to see for example for the case 1, something like image "2" but for the case 3 something like figure "4" see below with also different heat flux value in each time step comparing each case.

      when I apply DO or S2S only with no solay ray tracing in both, I get these images below where heat flux values are close to 0

       

      I hope to explain my issues properly and I am sure this post will help many beginners that needs to understand solar load calculation how works.

      Regards and thanks in advance

    • AG
      Ansys Employee
      1. Details of solar load (Fair Weather Conditions) as you are pointing in Table, is printed to fluent console or trn file whenever Solar Load Updates. By default it is set to 10 by Update Parameter "Time Steps per Solar Load Update=10". If you wish you can change it to 1 to get these details per timestep as you mentioned.
      2. In second part of your question, its not clear which images you are referring to. Check details on S2S and DO model and verify if you are using correct boundary conditions to expect variation in results. DO model is used when you have a participating media or transperent solids. So check your material properties or boundary conditions to further expect variation in results with these models.
      3. In last part where you are refering 0 heat flux on wall. I think you dont have any other heat source or higher temperature wall in your domain. Solar load is the one and only source of energy in your domain and when you switch it OFF, you are observing almost 0 flux. 

      Thanks. 

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