The Influence of Storage Tank Volume on the Nighttime Heat Dissipation and Freezing Process of All-Glass Vacuum Tube Solar Water Heaters

The issue of freezing often occurs when using all-glass vacuum tube solar water heaters during cold winter seasons, leading to problems such as pipe ruptures and tank leakage. In order further study the nocturnal heat dissipation characteristics these heaters, a three-dimensional transient numerical model their was established. simulated process, experimental validations were conducted through temperature drops collector individual tubes without storage tank. Experimental simulation results revealed that in clear weather conditions winters Luoyang, experienced issues night, with predominantly starting from bottom surface tubes. frozen length along wall thickness ice at section reached up 1180 mm 5 mm, respectively. absence tank, situation severe, approximately 4/5 completely frozen. Under specified operating conditions, different volumes exhibited varying degrees heaters. When volume increased 15 L, drop decreased by 12.1% 7.6%, Larger resulted reduced risks collectors. This provides valuable guidance for design application collectors serves reference development energy utilization technologies.