| Heat transfer during two phase flow frequently encountered in oil and gas industrialproduction. Therefore, The design of such equipment as condensers, heat exchangers weredependent the knowledge of fluid dynamics and heat transfer process during forcedconvective. The occurrence of paraffin deposition on the pipe wall in wellbores and pipelinesis another key. The accurate predict can effectively prevent wax and hydrate plugging,optimize site operation, and bring significant economic benefits.A systematic experimental study was carried out on the heat transfer and hydrodynamicof air-water two-phase flow in horizontal tube, upward1°and3°pipes. Electrical probeswere used to measure the slug parameters. Good agreements were observed between themeasurements and the predictions.The heat transfer coefficient of water-air two-phase flow was influenced by thesuperficial velocities of liquid and gas. Generally, htpincreased as Vslincreased for a fixed Vsg.In addition,at a constant Vsl, htptypically increased with increasing Vsgand passed through amaximum then decreased as Vsgincreased. The effect of the gas flow rate on increasing htpwas more pronounced at low Vsl,and was not so remarkable at high Vsl.Based on the experimental measurements, the influence of the slug parameter on theconvective heat transfer coefficient was analyzed firstly. The length of slug and elongatedbubble represent the share of the slug and elongated bubble in slug unit; the unit cellfrequency represent the slug number which through the text section during per unit time;These factors determines the gas-liquid two phase heat transfer characteristics of the slug flow.Based on the accurate parameter values,improve the existing model, the new model can bepredictions more accurate.A new two-phase heat transfer correlation is obtained, which based on the Gnielinskicorrelation and used multiparameter fitting. The deviation between the experimental resultsand the predicted values for upward1°and3°pipes were-6.13%and-15.15%. |
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