Experimental Investigation of Heat Loss from a Passive DMFC using Differential Interferometer

Abstract

AbstractThe knowledge of heat loss from the fuel cell will be helpful to decide on material components and fixture design. In the present study, a new methodology is proposed to estimate heat loss from passive DMFC using interferometry technique. Printed circuit board (PCB) fixture is adapted in our study that replaces end plate and current collector. The accurate cell temperature distribution is useful to estimate the heat from the cell fixture. The cell temperature distribution is measured based on infra‐red (IR) thermography and this temperature distribution is used to estimate the heat transfer coefficient of the fuel cell. Differential interferometer (DI) technique is used to estimate the heat transfer under different operating conditions of the fuel cell. The cell surface temperature measured on the cathode gas diffusion layer (GDL) is 42 °C for 5M methanol concentration whereas for 1M, it is 32 °C. Based on the analysis , the average heat transfer coefficient of the cell at vertical PCB rib orientation using 5M methanol concentration is estimated to be 2.7 Wm−2 K−1. A two‐dimensional non‐isothermal single‐phase half‐cell (cathode) model is developed and compared with experiments. The cell temperature distribution obtained from model is in good agreement with experiments. The model is extended to study the effect of PCB orientation and thermal conductivity of PCB material on heat loss. The cell at vertical PCB rib orientation retains 15 ‐ 20% more heat than horizontal rib. Therefore, the cell temperature showed 42 °C and performed 10% better compared to horizontal PCB rib.