AST for thermo-structural analysis

[Rickfds]

Hello,
I want to use the AST from FDS as an input for a thermo-structural analysis. If I understood it right one way to think of the AST is that it is the "effective" exposing temperature that accounts for both radiation and convection and that the AST would provide the effective furnace temperature of a structure in a controlled furnace.
For the thermo-structural analysis I want to set for the structure the emissivity=0.8 and the heat transfer coefficient=35 W/m²K and then use the fds-output AST as the “effective" exposing temperature for the heat transfer into the structure.
So am I right that I have to define in FDS the EMISSIVITY=0.8 and the HEAT_TRANSFER_COEFFICIENT=35 of the surface for which AST is calculated?

[RIO4FDS]

Take a look at equation 22.38 in FDS Users Guide (and its references) and be sure that you are using the same equation (or the same terms) to calculate the input into your thermo-structural model. In some codes you need to add convection and radiation terms separately.

To recreate the same exposing condition in your thermo-structural code, you should transfer from FDS the variables used to calculate AST (fixed or time-dependent).

The use of some simplifications, like, a constant heat transfer coefficient to the whole surface, depends on your scenario and structure.

Take a look at fds2ftmi: https://drive.google.com/drive/folders/0BzJEIogPt2TyfnFERGNQNFVnWXJ4aXd5bFRhRzNDSktSN1o1dERFT3ZwaHJxNkM1T0ZMeXc?resourcekey=0-d5AdP45Gi4TWutPNUXz9rg&usp=drive_link