Sequential inverse method implemented into CFD software for the estimation of a radiation boundary

An inverse method was implemented in commercial CFD software to estimate the wall temperature of a simplified baking oven from the initial estimate of an inert baking product temperature located in the oven. The transport phenomena were modeled with the energy equation, the RANS equation (Reynolds-Averaged Navier–Stokes), the k-epsilon realizable turbulence model and the S2S radiation model. The optimisation approach was used, by formulating an objective function. The proposed method was sequential and the objective function was minimized at every given time step. The minimization iterative process was introduced within the CFD solver loop, therefore solving both field variables and the inverse problem at once. To address the noisy input data, two techniques were compared: 1- Tikhonov regularization 2- pre-filtering of data and evaluated for two different bakery products. Results showed that the pre-filtering method provided more accurate estimates and avoided the need for a realistic initial estimate of the wall temperature.

► Hot walls emitting radiation in oven are typically not monitor in practice. ► An inverse boundary problem is solved for a bakery oven model. ► The inverse method is implemented in CFD software using a sub-routine. ► Inverse problem, flow field and heat transfer are converged synchronously. ► Using measurement inside the oven, temperature of a radiating wall is estimated.