Melting Performance of Phase Change Material in Asymmetric Partitioned Enclosures Under Hypergravity

Phase change materials (PCMs) have gained considerable attention in avionics applications, where aircraft and onboard electronic systems experience hypergravity (HG) during maneuvering. However, the melting behavior of PCMs in asymmetric partitioned enclosures under HG remains insufficiently explored. In this study, PCM melting in a stepped asymmetric partitioned enclosure is numerically investigated under HG for three aspect ratios ([Formula: see text], 0.5, and 0.33), with a 5% partition plate volume. The analysis considers configuration orientation, partition arrangement, HG effects, and comparison with nonpartitioned and symmetric configurations. Results show that downward configurations with lower [Formula: see text] enhance melting rates across all gravity levels, whereas upward configurations exhibit an initial improvement followed by a decline. The downward design with [Formula: see text] reduces energy storage by 4.4–5% while shortening melting time by 56.4–68.8% compared to the nonpartitioned case. Velocity analysis reveals stronger natural convection in upward configurations. For lower [Formula: see text] downward designs, two distinct peaks in the maximum velocity are observed, with a weaker secondary peak at later times, indicating gravity- and geometry-dependent convection intensity. The enhancement is attributed to intensified buoyancy-driven convection associated with an increased Rayleigh number. However, the enhancement effect diminishes with increasing gravity, indicating practical gravitational limits.