5.2.2  BEAMA design recommendations


The thermal design procedures set down in the BEAMA design recommendations are very similar to those followed by the HEI, except differences occur in the statements regarding tube cleanliness, and the correction factor for cooling water temperature as applied to the overall heat transfer coefficient (Fig 4.17).

Graph indicating differences in assumptions made by HEI and BEAMA design documents

The curves for the BEAMA heat transfer coefficients are based on tubes in the brushed-clean condition and include an allowance for the normal oxide film coatings which are an inherent feature of any tube during its operational life, whereas the HEI curves relate to tubes in the clean, as-new condition. In addition, the BEAMA curves for cooling water temperature correction are based on a mean temperature, and not on tube inlet temperature as in the HEI curves.

Taken collectively, these departures have very little effect on any design, providing due recognition of these differences is made.


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