The baffle height for standard 25 percent cut baffles equals (where D = shell inner diameter) ?
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Answer: C. 0.75 D
Explanation
Standard 25 percent cut baffles block one quarter of the shell cross-sectional area. The baffle height, representing the remaining window opening, equals seventy-five percent of shell diameter. Geometric calculations for 25 percent cut baffles establish the window height precisely at 0.75 D. Baffles support tube bundles and direct shell-side fluid across tubes to enhance heat transfer. Baffle cut percentage refers to the fraction of shell diameter removed to create flow windows. Standard baffle cuts typically range from 15 to 45 percent depending on pressure drop limits.
Heat exchanger fabricators follow TEMA standards to determine exact baffle geometries and cuts. Proper baffle window design prevents flow stagnation and destructive fluid-induced tube vibration. Engineers specify baffle cuts to balance shell-side heat transfer coefficients against pressure drops. 0.25 D represents the baffle cut height rather than the remaining window opening height. 0.50 D corresponds to a 50 percent baffle cut configuration instead of a standard 25 percent cut. Option D is incorrect because 0.75 D is the exact standard measurement for 25 percent cut baffles.
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- Engineering
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- Chemical Engineering
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