Magnesium-manganese-oxide redox materials have significant potential for thermochemical energy storage; however, the material high-temperature physical properties, in particular, its thermal conductivity are critical for engineering storage devices.In this thesis, the effective thermal conductivity of packed beds of magnesium-manganese-oxide pellets is measured in the temperature range of 300 ℗ʻC to 1300 ℗ʻC with a 100 ℗ʻC span using the transient hot-probe method. The transient hot-probe method is a well-established technique to determine the effective thermal conductivity of materials by measuring the transient temperature response of a 1-D heat source with constant heat generation. In this thesis, a thin platinum wire covered by a thin alumina sheet is used as both 1-D heat source, and the temperature measurement device. A constant current is passed through the platinum wire emulating 1-D heat generation. Simultaneously, the electrical resistance of the wire is measured versus time by measuring the voltage across the platinum wire. The wire temperature is calculated based on the wire's temperature-dependent resistance using a calibration curve established prior to the experiment. The effective thermal conductivity is calculated by curve-fitting a conductivity-dependent model to the wire temperature. The effective thermal conductivity ranges from 0.46 to 1.64 (W/(mK)), and increases significantly with the temperature. The increase in thermal conductivity with temperature is primarily attributed to thermal radiation. The experimental results are compared to a theoretical dual-porosity model, showing good agreement.
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