Design, Manufacturing and Testing of Primary Separators to Removal of Condensed Water at the Inlet of PEMFC

One of the main problems in reducing performance and life time in polymer electrolyte membrane fuel cell stacks is reduced performance due to flooding and as a result fuel starvation. One of the approved parameters in the voltage drop of the primary cells of the fuel cell module is the flooding caused by condensed water at the dehumidifier outlet gasses. To prevent this water from entering the elementary cells, it is recommended to make an initial separator. For this purpose, in this paper, the requirements of the initial separator design are stated and then a design is presented according to the assumptions of the problem. Then, by presenting the test setup, the desired parameters are designed, controlled and, if necessary, reviewed, and at the end, the results are presented. The results showed that with the special geometrical parameters the flow rate of initial separator can be controlled and without and sensible change in the PEMFC stoichiometry is applied Stable and continuous operation of a fuel cell requires proper operation of all its components. One of the causes of dysfunction of the fuel cell is the presence of liquid water at the inlet of the fuel cell and its penetration into the primary cells and as a result their flooding. The primary separator is designed to prevent liquid water from entering the primary cells with a structure compatible with the fuel cell. In designing an initial separator, the items in Table ۱ should be considered [۱-۲]. Figure ۱ shows the design of the initial separator and its prototype. All requirements and geometric constraints are considered in its design Also, the flow rate through the separator at different pressures for oxygen gas is shown in Figure ۲. According to the flow rate in the pressure difference between the inlet and outlet manifolds, the design has been able to meet the requirements and design constraints. An innovative plan is presented for collecting and directing liquid water in the stack inlet manifold. This design has been able to prevent flooding and voltage drop in the initial cells of the stack by observing the requirements and geometric and functional constraints. At the same time, due to the design proportional to the pressure drop between the output and input manifolds, there is no significant change in the stoichiometry of the stack

کلیدواژه ها:

Separator ، PEMFC ، Flooding ، Pressure drop