| Chemical oxygen sources are popular with the aero/astrospace and mining communities because they can provide a great quantity of oxygen from a small package. Lithium perchlorate has the potential to be an excellent chemical oxygen source in a reactor which supplies oxygen at an adjustable rate. In order to avoid the use of moving parts in the reactor feed system, a capillary pumping scheme has been envisioned to move the molten salt from a relatively cool storage reservoir to a hot reaction zone within the porous medium where the liquid decomposes liberating oxygen. The oxygen flow control concept could include feedback control of the reaction zone temperature with a radiant heater. In order to develop such an oxygen generator reactor, the fundamental processes that control the bulk transport and reaction within the porous medium must be studied, defined and characterized. A lumped parameter model is proposed where the wick reactor tends to operate through a series of sequential processes at the pore level. This lumped formulation yields a parameter which enables construction of a distributed, finite-volume, steady-flow model of the wick reactor where there is complete coupling between the conservation equations. These models compare well to the data acquired through a series of experiments performed on a variety of sintered particle wicks. Qualitative predictions and conceptual arguments appear to capture the observable qualitative characteristics of the experimental reactors. The quantitative predictions yielded by the distributed model are good agreement with the measured output of a wick specifically designed and fabricated for high output. Simulation and experimentation results are summarized in a wick operating regime map. |
