![]() ![]() In this study, the effect of single (1-S), double (2-S) and triple (3-S) serpentine flow field configuration on the performance of PEM fuel cell (PEMFC) was investigated both numerically and experimentally. Nomenclature: A, area (m 2) a c, surface-to-volume ratio (m 2 /m 3) a, water activity D i, diffusivity of specie i (m 2 /s) h, enthalpy (J/mol) h c, free convection heat transfer coefficient (W/m 2 K) I, current (A) i, current density (A/m 2) i 0, volumetric reference exchange current density (A/m 3) k, gas permeability (1/m 2) M w, molecular weight (kg/kmol) P, pressure (Pa) p sat, saturation pressure (Pa) p v, vapor pressure (Pa) R, volumetric transfer current (A/m 3) R, universal gas constant (J/K-mol) r w, condensation rate (kg/m 3-s) s, liquid water volume fraction T, temperature (K) u, v, w, velocity components (m/s) V, volume (m 3) V, voltage (V) F, Faraday's constant (C/Kmol) Greek symbols: σ, electrical conductivity (1/ohm-m) ϕ, electric potential (volts) j ref, reference exchange current density per active surface area (A/ m 2) ζ, specific active surface area (1/m), ref, local species concentration (Kmol/m 3) γ, concentration dependence α, transfer coefficient η, surface over potential h react, net enthalpy change due to the electrochemical reactions R ohm, ohmic resistivity of the conducting media h L, enthalpy change due to condensation/vaporization of water The ECSSFF has shown superior performance over the triple serpentine design under all these conditions. ![]() A parametric study is carried out by varying operating conditions, viz, cell temperature and inlet humidity on air and fuel side. The performance is evaluated in terms of their polarization curves. The performance of PEMFC with ECSSFF has been compared with the performance of triple serpentine flow design on cathode side by keeping all other parameters and anode side flow field design similar. ECSSFF design is used for cathode part of the cell and parallel flow field on anode part of the cell. ![]() In the current work, a detailed performance study of enhanced cross-flow split serpentine flow field (ECSSFF) design for PEMFC has been conducted using a three-dimensional (3-D) multiphase computational fluid dynamic (CFD) model. The problem of inadequate water evacuation and improper reactant distribution become more severe and these designs become worse at higher current loads (low voltages). But these flow fields have inherent problems of high pressure drop, improper reactant distribution, and poor water management, especially near the U-bends. Most generally used flow channel designs in polymer electrolyte membrane fuel cells (PEMFCs) are serpentine flow designs as single channels or as multiple channels due to their advantages over parallel flow field designs. ![]()
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