Bionic topology optimization of fins for rapid latent heat thermal energy storage

•Bionic topology optimal fins considering natural convection and different objective functions.•Melting/solidification process simulation of different optimization results.•Bionic analysis from the morphology and fractal dimension.•Non-linear dynamic analysis in melting process. The latent heat storage (LHS) technique has been widely applied in various thermal energy conversion and management fields. However, LHS device suffers from very slow heat storage/release process. Here, a bionic topology optimization method is proposed to enhance thermal storage/release performances considering different objective functions and heat transfer mechanisms. Taking minimized capacity dissipation as the optimization function and considering natural convection, the optimized fin structure can reduce the melting and solidification time by 93% and 80%, respectively. The underlying mechanism can be attributed to better synergy between flow and heat transfer. Moreover, the fractal dimension of optimized fins is similar to the leaf structure. This research provides a new route for the design of high performance LHS devices, and promotes the application of bionics in thermal energy storage fields.