{"id":357595,"date":"2024-03-18T11:54:07","date_gmt":"2024-03-18T11:54:07","guid":{"rendered":"\/forum\/forums\/topic\/under-low-velocity-there-is-difference-between-hand-calculation-and-simulation\/"},"modified":"2024-03-18T11:54:07","modified_gmt":"2024-03-18T11:54:07","slug":"under-low-velocity-there-is-difference-between-hand-calculation-and-simulation","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/under-low-velocity-there-is-difference-between-hand-calculation-and-simulation\/","title":{"rendered":"Under low velocity, there is difference between hand calculation and simulation"},"content":{"rendered":"

The simulation model is a simple jacketed tube model.<\/p>\n

<\/p>\n

The flowing fluid is air, which is available in fluent by default, and the jacket material is aluminum which is modified the thermal conductivity of the initial aluminum to 1e-5 W\/m K.<\/p>\n

The inlet is set as mass flow inlet (4.02577e-9 kg\/s, 26.8 K) (velocity is about 4e-5 m\/s) and the outlet is pressure outlet.<\/p>\n

The boundary temperature of tube is set as 300 K.<\/p>\n

The flow state in the tube is laminar.<\/p>\n

The calculations all converged, but the gas heat absorption (m cp T), calculated from the temperature difference between the inlet and outlet, is in significant error(about 200%~300%) from that calculated from the intrusion of heat flux at the tube wall (q” A).<\/p>\n

 <\/p>\n","protected":false},"template":"","class_list":["post-357595","topic","type-topic","status-closed","hentry","topic-tag-fluent"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t