Recycle Effect on Double-Pass Concentric Circular Mass Exchangers under Uniform Wall Fluxes

✍ Scribed by C.-D. Ho; Y.-C. Chuang; J.-W. Tu

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 510 KB
• Volume: 31
• Category: Article
• ISSN: 0930-7516
• DOI: 10.1002/ceat.200800244

✦ Synopsis

Abstract

A study on improvement in device performance of a double‐pass concentric circular mass exchanger with uniform wall fluxes and external refluxes was conducted under counterflow operations. The linear superposition of an asymptotic solution and a homogeneous solution with the use of an orthogonal expansion technique for solving such a conjugated Graetz problem is formulated theoretically and the analytical predictions are applied to investigate a substantial masstransfer improvement. A mathematical expression for the average Sherwood numbers and the outlet dimensionless concentration is given. Comparisons of analytical results are made with the single‐pass operations of the same working dimensions (without permeable barriers inserted and without recycle). Considerable device improvement in mass transfer rate is obtained by introducing the recycle‐effect concept in designing such double‐pass devices. The effect of permeable barriers on the mass‐transfer efficiency improvement as well as on the power consumption increment has also been delineated.