A Fifth-Coordinate Heat Pump: Coefficient of Performance for Phase-Assisted Heat Transport

This paper presents a complete design study of a heat pump that moves part of its heat along a phase coordinate, computed throughout from stated assumptions. At a temperature lift of 45 K the combined coefficient of performance is 3.65 against 3.08 for the fluid cycle alone. At a lift of 60 K the figures are 2.90 combined against 2.31 fluid-only, while at a small lift of 15 K the combined machine reaches 7.50 against 9.24 for the fluid cycle, so the advantage concentrates at large lifts. Every figure is a computed result of the stated model and nothing was built or tested: the study is SIMULATED, NOT MEASURED, and its limits are stated as plainly as its performance.