Thermocouple sheet sensor

We investigated a thermoelectric thermal sensor which responded to heat in a short time and generated electricity to drive electric parts such as a light emitting diode or a piezoelectric buzzer. The sensor was composed of the insulated metal sheet and thermoelectric thick films on it. The device contained 8 pairs of iron disilicide thermocouple connected in series, generated 1.5 V within 5 seconds and 2.8 V within 25 seconds reacting to a gas flame. 

Temperature Profile n (1) In extrusion or injection molding, the sequence of barrel temperatmes from feed opening to head, sometimes presented as a plot of temperatme versus longitudinal position, hence profile. (2) The sequence of metal temperatmes across a sheet or film die, or around a large blown-fihn die. (3) The sequence of temperatmes across the width of a slab of newly extruded or cast plastic foam, is indicated by temperatme sensors placed laterally at the same depth in the foam. (4) In analysis of Nonisothermal, laminar flow of very viscous liquids (e.g., polymer melts) within tubes and dies, the sequence of temperatmes from the one sidewall through the center to the opposite sidewall at any point along the axis of flow. Such profiles have also been measured experimentally with traversing thermocouples. 

For fundamental research where the thermal parameters are not precisely known and to define unknown thermal transport parameters, we would like to directly measure the temperature profile within the electrolyte. To approach this problem, a thermocouple can be embedded directly in the diffusion media of a PEFC [32, 33]. However, the contact resistance between the diffusion media and the thermocouple becomes another unknown parameter. To circumvent these difficulties, Burford et al. invented a method to embed an array of microthermocouples directly between two 25-pm-thick Nafion electrolyte sheets of a membrane electrode assembly [34, 35]. Local temperature variation in PEFCs was determined to reach > 10°C at high current density for a thick diffusion media (>400 pm for woven cloth media). This proved that an isothermal assumption is typically not justified over a full range of performance and indicates phase change plays a role in water transport in PEFCs. An even smaller MEMs-based thermosensor array has been developed using vapor deposition [36] and has been embedded within a PEFC electrolyte, providing precise locational control of the sensor position. 

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