HW2Problem3

HW2Problem3 - A uniformly heated rod bundle has operating...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Critical Heat Flux 23 1 A uniformly heated rod bundle has operating characteristics given below. The critical heat flux mechanism is dryout, and can be correlated by the Hench-Levy correlation as ′′ = −− q xx xG x x x x x c cc c c c 10 1 19 33 07 3 10 06 07 009 2 6 1 26 12 2 .( ) . . . t a n h ( / ) () .. . t a n h ( /) ( ) where: . . t a n h ( ) . . tanh ( / ) . tanh ( / ) G c c 1 2 0 273 0 212 3 10 05 0 269 3 10 0 0346 2 10 =− + Assuming a minimum Critical Heat Flux Ratio of 1.0, determine the maximum heat flux the channel can safely operate. Problem Data Channel Mass Flux 1.33 x 10 6 lbm/hr-ft 2 Rod Pitch 0.640 inches Rod Diameter 0.493 inches Channel Pressure 1000 psia Channel Height 146 inches Inlet Temperature 532 F SOLUTION The critical heat flux decreases monotonically with quality and therefore position up the channel. For a uniformly heated channel, the minimum critical heat flux ratio will then occur at the channel exit. The critical quality is given by fg f crit crit h h h x = where m DH q h h in crit ± π + = such that
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

HW2Problem3 - A uniformly heated rod bundle has operating...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online