Ultra-low temperature frosting in cryogenic engineering: Mechanisms, methods, features, and control strategies

Frosting below −100 °C represents a distinct cryogenic regime in which vapor deposition is governed mainly by desublimation, high supersaturation, and limited surface diffusion rather than conventional condensation–freezing. This review synthesizes recent advances in ultra-low temperature frosting, emphasizing the mechanisms, morphologies, modeling approaches, and frost-control challenges that distinguish cryogenic systems from ordinary refrigeration conditions. Reported studies show that desublimation-driven growth produces highly porous and irregular frost structures, including wisteria-like, shrub-shaped, and thread-like morphologies, which rapidly increase thermal resistance and degrade the performance of LNG vaporizers, aerospace precoolers, and related cryogenic equipment. Existing simulations confirm the dominant role of vapor-phase mass transfer and frost–fog coupling, but remain limited by simplified geometries, incomplete validation, and insufficient representation of frost deformation, detachment, and structural evolution. Surface-based anti-frosting strategies developed for moderate subzero conditions show reduced effectiveness in this regime, indicating the need for integrated diagnostic, modeling, and de-/anti-frosting frameworks specifically designed for cryogenic environments. This review identifies the critical knowledge gaps and provides a unified basis for future prediction and control of ultra-low temperature frosting.