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(a) is a vertical DWHR device with a quadruple copper helix , (b) is a vertical device with a single copper helix , (c) is a vertical device with straight cold water pathways , (d) horizontal design .
Schematic of the experimental setup.
DWHR device drawing with cross-sectional views.
Temperature response at a flow rate of (a) 1.5 gpm, (b) 2 gpm, (c) 2.5 gpm, and (d) 3 gpm.
Transient experimental effectiveness data at different flow rates.
Fraction distribution of hot water draws over 24 h.
Comparison of hourly energy consumption profiles for a water heater with and without a DWHR device.
Cumulative daily energy consumption comparison of a water heater with and without a DWHR device under steady and transient operations.