Inlet manifold tests and performance evaluation of dephlegmators in air-cooled steam condensers

[摘要] ENGLISH ABSTRACT:Measurements on air-cooled reflux steam condensers or dephlegmators at differentpower plants have shown that sections of these units do not transfer heat effectivelyover a range of operating conditions. The ineffective sections may be due to flooding inthe finned tubes although entrainment of condensate in certain steam inlet manifolds isusually the main reason for the poor performance.In this dissertation factors that limit effective dephlegmator operation are discussed andthe influence of two inlet manifold designs on dephlegmator operation is investigated.Laboratory experiments are conducted to show under which conditions liquidentrainment occurs and to visualize the flow distribution within the respectivemanifolds.An alternative, essentially horizontal arrangement of the dephlegmator is proposed. Inorder to evaluate the performance of such a system, the heat transfer and pressure dropon the steam-side is determined experimentally in an air-cooled finned tube. Noflooding was observed during tests conducted at zero and negative tube angles to thehorizontal.

[发布机构] Stellenbosch University