2018 - Sustainable Industrial Processing Summit & Exhibition
4-7 November 2018, Rio Othon Palace, Rio De Janeiro, Brazil
| Explosive Forming of Metal Tubes for Heat Exchangers Andras Szalay1; Athanasios G. Mamalis2; Istvan Zador3; Pal Racz4; Hasebe Toshiaki3; 1S-METALLTECH 98 MATERIALS RESEARCH AND DEVELOPMENT LTD, Budapest, Hungary; 2PC-NAE, DEMOKRITOS NATIONAL CENTER FOR SCIENTIFIC RESEARCH, Athens, Greece; 3S-METALLTECH 98 LTD, Budapest, Hungary; 4BAY ZOLTáN NONPROFIT LTD, Budapest, Hungary; PAPER: 86/Manufacturing/Regular (Oral) SCHEDULED: 17:10/Tue./Sao Conrado (50/2nd) ABSTRACT: Large quantities of hot flue gases are generated from kilns, ovens, and furnaces. If some of this waste heat could be recovered, a considerable amount of primary fuel could be conserved. Although the energy lost in waste gases cannot be fully recovered, much of the heat could be recovered by heat exchangers or recuperators, and the loss will be reduced. A heat exchanger is an equipment built for efficient heat transfer from one medium to another. Generally, the two media are separated by a solid metallic wall, so that they never mix. These tubular heat exchangers are widely used in power plants, chemical plants, and metal processing plants. The main requirement for heat exchanger tubes is that the heat transfer between the media inside the tube and outside the tube should be at the maximum. This can be achieved in many ways; the most frequently used solution is the modification of the tubes construction as creation of enhanced surface, or applying spiral strips for causing turbulence in the streaming media. An innovative solution is enhancing the efficiency of the heat exchanger tubes by creating spiral deformations on the tubes. The advantages of the properly designed deformation of the tube material are twofold: on one hand the heat transferring surface of the tubes will be enlarged, and on the other hand the deformations will cause turbulence in the streaming media, enhancing the heat transfer. The task can be solved by explosive tubeforming [1]. The optimal form of the tubes have been designed by thermo-hydraulic computer simulation based on the ANSYS system [2]. The plastic deformation of the tubes is carried out by high pressure shock waves created by explosion of detonating cords positioned on the outer surface of the tubes. The efficiency of the heat exchangers built with explosively formed tubes are cca. 10 % higher than the heat exchangers built with plain tubes. In this presentation we briefly report the results of the simulations and introduce the manufacturing process. References: [1] Prümmer R, Explosive Welding, Forming and Compaction. Ed. T.Z. Blazynski, Applied Science, London 1983. [2]. A.Szalay, A. G. Mamalis, I. Zador, A. K. Vortselas, L. Lukacs: Explosive metalworking: experimental and numerical modeling aspects International Symposium on Explosion, Shock wave and High-energy reaction Phenomena 2013 March 27 - 29, 2013 Nago, Okinawa, Japan |
