A novel method of in-situ temperature distribution measurement of solid oxide fuel cell stack

Abstract

A novel method for measuring the in-situ temperature of the Solid Oxide Fuel Cell (SOFC) stack is developed. Multiple optical silica fibers with a 0.4 mm diameter were integrated into a 3 × 3 array which was plugged into a 1 kW stack. The in-situ temperature of the stack with different loads in steady-states and dynamics operating conditions was tested within a furnace heated up to 750 °C. By moving the fiber array using a three-axis manipulator, the temperature distributions along the cathode flow channels were scanned and the measurement resolution was set to 1 mm. For the current load with 10 A, 20 A and 30 A in a steady-state, the experimental results show a clear trend of higher temperature on outlet and top of the stack in steady-state. The maximum temperature differences inside the stack were more than 44 °C for 30 A. During the processes of the start-up, current linearly increased from 0A to 10 A, 20 A and 30 A individually with a fixed slope of 2.5 A/min and the current was maintained for 20 min, the maximum temperature of the stack raised to 766 °C, 783 °C and 805 °C, respectively. Moreover, the dynamic responses of the temperature with fluctuating inputs such as a rapid step loading and unloading test from 0 A to 30 A and 30 A to 0 A in 4 min recorded that the temperature change rate inside the stack was within 1 °C/min, which shows a capability of quickly power adjusting of SOFC.