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3 Experiments in Pebble Bed Heat Transfer
3.3.4.1 Sensitivity Analysis
In the inverse method, sensitivity is used to distinguish different effects of estimated
parameters on the computed temperature T ( P). The normalized sensitivity coefficient is defined by
X
i, j = |p
j |
∂ T i ( P)
∂ p j
(3.47)
where i is the same subscript as Eqs. (3.11) and (3.12), and j indicates different
estimated components in P.
Figure (3.17a) shows the normalized sensitivities of ten parameters of the piecewise function of the effective thermal diffusivity at the optimal solution, and
Fig. (3.17b), shows the normalized sensitivities of six thermocouple positions at
Fig. 3.17 Normalized
sensitivity coefficients of (a).
diffusivity parameters with
the C1 set data of first
vacuum test, and (b).
thermocouple positions of
T1–T6