Wire-plate and sintered hybrid heat pipes: Model and experiments

• A new hybrid heat pipe technology that associates high liquid pumping capacity with the low liquid pressure drop is proposed.
• A theoretical and experimental thermal study of a wire-plate and sintered hybrid heat pipe is presented.
• A parametric study of the influence of the major design parameters in the heat transfer performance is performed.
• The maximum heat transfer capacity of the heat pipe are mathematically determined by the models.
• An experimental setup was built and several heat pipes were constructed and tested.

A new hybrid heat pipe technology that associates high liquid pumping capacity of sintered metal powder structures with the low liquid pressure drop of diffusion welded wire-plate grooves is proposed in this work. It consists of covering both internal surfaces of the heat pipe casing plates, in the evaporator region, with layers of sintered metal powder wicks, while the wick of the adiabatic and condenser sections consist of grooved structures, sandwiched between the metallic casing plates and wires welded by diffusion process. Hydrodynamic and thermal models were presented, composed of models developed in this work and others taken from the literature. These models were used to design several hybrid heat pipes that were tested in an experimental setup especially constructed for this purpose. The theoretical models, used for the prediction of the maximum heat transport limit and of the temperature distribution along the heat pipe, compared very well with data, showing their excellence. Also, several parameters that affect the thermal performance of this device were studied, and, among them, the geometry of the sintered porous media and the inventory of the working fluid showed to be the most important ones.