Comparative analysis of different strategies exploiting the adjoint topology optimization method for enhancing the performance of a cooling device equipped with micro-channels

An array of micro-channels in parallel connected by Z-manifold, under consideration for the cooling of MW-class gyrotron cavities for fusion applications, is analyzed here. The micro-channels should allow the removal of a very non-uniform heat load, which can reach a peak up to 25 MW/m2. The adjoint topology optimization method is applied to the manifold regions. In the first case study, the micro-channels are not equally spaced but rather distributed and a uniform flow distribution in the micro-channels is targeted. In the second case study, a uniform micro-channels distribution is considered, but a flow rate distribution shaped to follow the heat load is targeted. The results suggests that a uniform flow repartition among the channels is more easy to achieve with respect to the non-uniform one, which would possibly require some additional modification of the channel geometry, on top of the shaping of the manifolds.