Research PaperExperimental comparison of the thermal performances of acetanilide, meso-erythritol and an In-Sn alloy in similar spherical capsules

- Performances of three PCMs in similar spherical macro-capsules studied.
- Meso-erythritol had the best charging performances.
- Subcooling affected quality of heat discharged by acetanilide and meso-erythritol.
- The In-Sn alloy is a superior PCM for medium temperature heating applications.

The thermal performances of acetanilide, meso-erythritol and an In-Sn alloy, as phase change materials (PCMs) for medium temperature applications, inside separate, spherical aluminum capsules are investigated. The average radial temperatures in the capsules are used for analyses during the charging and discharging experiments. The influences of the HTF flow rate during simultaneous discharging of the encapsulated PCMs are also investigated. Meso-erythritol showed the greatest charging rates at all HTF flow rates and HTF charging temperatures considered, followed by the In-Sn alloy and lastly by acetanilide. The influences of HTF flow rate during simultaneous discharging of the encapsulated PCMs are also investigated. Large subcooling exhibited by acetanilide and meso-erythritol greatly reduced the quantity of discharged thermal energy that is useful for the intended application. The In-Sn alloy, due to the very little subcooling it exhibits, discharged the highest quantities of useful thermal energy at all the flow rates considered.