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This study investigated determination of physical and thermal properties of herbal compress ball. These properties are dispensable for studying heat transfer mechanism and process because herbal compress balls are generally heated by steam before use. Some physical and thermal properties of dried herbal compress ball were measured and characterized in this study. Some reliable measuring methods of such properties as well as in-house-made gas expansion pycnometer were developed. Experimental results showed that significant physical and thermal properties were successfully measured and in-house-built apparatus could work well with small error (+0.70%). Also, it was obvious that the temperature change in herbal compress ball was strongly affected by diffusion of steam inside the herbal compress ball and its thermal conductivity was close to that of woods.
Keywords: Herbal compress ball, physical properties, thermal properties, heat transfer
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