CONTINUOUS-CIRCULATION CALORIMETRY AND FLOW-SPLIT UNCERTAINTY IN A TWO-BRANCH SOLAR RADIANT-FLOOR SYSTEM WITH MACROENCAPSULATED RT52
DOI:
https://doi.org/10.5281/zenodo.23311785Abstract
A solar-driven hydronic radiant-floor experiment was re-analysed using a hydraulically explicit calorimetric framework in which the measured mass flow rate m belongs to the common line upstream of a split into conventional and PCM-integrated floor branches. The branch flow fraction fPCM was therefore treated as an unmeasured quantity, with fPCM = 0.50 used only as the nominal case and fPCM [0.30, 0.70] retained for sensitivity analysis. Because circulation continued overnight, the late-afternoon transition was identified as a genuine reversal of water-to-floor heat transfer rather than a pump shutdown. Under fPCM = 0.50, the control, system and PCM heat-flow reversals occurred at approximately 17:14, 17:15 and 17:16, respectively. The analysis provides a reproducible framework for separating exact hydraulic closure, conditional branch energetics and genuinely measured quantities in PCM-enhanced solar radiant-floor experiments.Keywords
hydronic radiant floor, calorimetry, parallel branches, flow-split uncertainty, heat-flow reversal, continuous circulation, PCM, solar heatingReferences
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