Simulation and Concept Evaluation of Extendable Lightweight Photovoltaic Modules for Vehicle Integration under Wind Loads

In this work, a design and concept evaluation of lightweight PV used for vehicle applications is shown, which uses honeycomb material as a supporting structure. Furthermore, the concept includes extendable modules to the side at the top of the vehicle which could higher the solar power output up to three-times when the vehicle is stationary. The mechanical properties of the honeycomb material depend on several design parameters and finding the right parameters can be time-consuming. Thereby, we present Shell-Solid-Shell approach with equivalent homogenized honeycomb core parameters to use it in a Finite-Element-Analysis (FEA) for structural mechanic simulation, which speeds up the design process and avoids time-consuming material tests. The ShellSolid-Shell approach was evaluated with three-point bending test, which shows good coincidence with only 2 % difference in deflection at maximum force comparing it to meso-scale modelling of the honeycomb material. Although the approach underestimates stiffness, resulting in a 40% difference in the flexural modulus of elasticity compared to the experimental data, we consider the Shell-Solid-Shell approach suitable for determining the correct honeycomb parameters. We define specific load scenarios for vehicle integration according to DIN EN 13561 and simulate a full-size lightweight honeycomb PV module. The simulation of the bare honeycomb material shows a good correlation between the analytical and numerical solutions, with a difference in maximum deflection of 9.6 %. Including the PV layers results in a maximum deflection of 40.4 mm for the module under a load of 84 N/m². Furthermore, we reduced the maximum deflection by performing a parametric study that increases the thickness of the lightweight honeycomb PV module. Increasing the thickness from 10 mm to 30 mm for the lightweight module reduces the deflection by 90%, while the weight increases by only 36%. These results provide valuable insights for the future development and integration of lightweight honeycomb structures in vehicle and other applications.