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The last paragraph in section Conduction Transfer Function Module of EnergyPlus documentation says:

The coefficients (CTFs) in the equation are constants that only need to be determined once for each construction type.

Following the derivation by Seem (1987), this seems true if the coefficient matrices A, B, C and D in state space representation given in section Calculation of Conduction Transfer Functions are constant matrices. The 2-node example of a simple one layer slab in the same section has convection heat transfer coefficient in A, B, C and D matrices.

How is this handled when a temperature dependent correlation like Walton etc. are used for convection coefficients? If the convection coefficient and matrices are updated every time step,wouldn't the transfer function coefficients be computed at every step? What am I missing here?

The last paragraph in section Conduction Transfer Function Module of EnergyPlus documentation says:

The coefficients (CTFs) in the equation are constants that only need to be determined once for each construction type.

Following the derivation by Seem (1987), this seems true if the coefficient matrices A, B, C and D in state space representation given in section Calculation of Conduction Transfer Functions are constant matrices. The 2-node example of a simple one layer slab in the same section has convection heat transfer coefficient in A, B, C and D matrices.

How is this handled when a temperature dependent correlation like Walton etc. are used for convection coefficients? If the convection coefficient and matrices are updated every time step,wouldn't the transfer function coefficients be computed at every step? What am I missing here?

The last paragraph in section Conduction Transfer Function Module of EnergyPlus documentation says:

The coefficients (CTFs) in the equation are constants that only need to be determined once for each construction type.

Following the derivation by Seem (1987), this seems true if the coefficient matrices A, B, C and D in state space representation given in section Calculation of Conduction Transfer Functions are constant matrices. The 2-node example of a simple one layer slab in the same section has convection heat transfer coefficient in A, B, C and D matrices.

How is this handled when a temperature dependent correlation like (like Walton etc. etc.) are used for convection coefficients? If the convection coefficient and matrices are updated every time step,wouldn't step, wouldn't the transfer function coefficients be computed at every step? What am I missing here?

The last paragraph in section Conduction Transfer Function Module of EnergyPlus documentation says:

The coefficients (CTFs) in the equation are constants that only need to be determined once for each construction type.

Following the derivation by Seem (1987), this seems true if the coefficient matrices A, B, C and D in state space representation given in section Calculation of Conduction Transfer Functions are constant matrices. The 2-node example of a simple one layer slab in the same section has convection heat transfer coefficient in A, B, C and D matrices.

How is this handled when a temperature dependent correlation (like Walton etc.) are used for convection coefficients? If the convection coefficient and matrices are updated every time step, wouldn't the transfer function coefficients be computed at every step? What am I missing here?