A twisted tape is a well-established and simple technology used since the 19th Century, a flat piece of metal or strip, twisted to obtain a regular pattern.
In order to design and use twisted tapes, a few variables have to be considered when these enhancement devices are specified.
The width of the twisted tape must be less than the tube inside diameter, with the thickness and the twist ratio being inter-dependant correlations that have to be specified at design phase. Design data and correlations are widely available in the public domain, but much of this information is considered to be old and specific to certain flow regimes. The modern research has looked into modifications of tapes and the issues of fitting inside a tube or more advanced studies on flow pattern in 2-phase applications.
The universal and comprehensive used correlations were studied by Manglik and Bergles, as they cover both laminar and turbulent flow and have been widely accepted and adopted as the basis for most of the heat transfer software calculation methods. Some of these corelations use a Reynolds number based on the equivalent tube diameter and others use the hydraulic diameter.
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A large variety of high-quality raw materials are stocked at CALGAVIN’s headquarters in Alcester, United Kingdom. From carbon steel, through to stainless steels or higher grades such as pure Nickel, Tantalum, Zirconium or Titanium – all ready to meet your requirements.
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