UC Irvine

As proton exchange membrane fuel cell technology advances, the need for hydrogen storage intensifies. Metal hydride alloys offer one potential solution. However, for metal hydride tanks to become a viable hydrogen storage option, the dynamic performance of different tank geometries and configurations must be evaluated. In an effort to relate tank performance to geometry and operating conditions, a dynamic, two-dimensional, multi-nodal metal hydride tank model has been created in Matlab-Simulink®. Following the original work of Mayer, Groll, and Supper1 and the more recent paper from Aldas, Mat, and Kaplan2, this model employs first principle heat transfer and fluid flow mechanisms together with empirically derived reaction kinetics. Energy and mass balances are solved in cylindrical polar coordinates for a cylindrically shaped tank. The model tank temperature, heat release, and storage volume have been correlated to an actual metal hydride tank for static and transient adsorption and desorption processes. The dynamic model is found to accurately predict observed hardware performance characteristics portending a capability to well simulate the dynamic performance of more complex tank geometries and configurations. As an example, a cylindrical tank filled via an internal concentric axial tube is considered. Copyright © 2006 by ASME.