Comment. The Lockett and Banik correlation confirmed the prediction of the Hsieh and McNulty correlation, and as expected, gave a more conservative answer. The weep fraction is small and can be tolerated. This conclusion is further supported by the observation that the minimum loads are about 50 percent of the maximum loads, and that a turndown of 2:1 is readily achievable by a sieve tray (Sec. 6.3.6).
Seal check. In Sec. 6.5.7, it was decided to go to clearances under the downcomers that exceed the outlet weir heights. For such designs, it has been recommended (1) that the clear liquid height in the down-comer under turndown conditions exceeds the downcomer clearance by at least 2 in. This will be checked here.
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