Flow Induced Vibration in a Heat Exchanger With Seal Strips

Flow induced vibration tests using water as the shell side medium were conducted on a shell and tube exchanger with single segmental baffles and various tube layouts. The heat exchanger was of the externally packed floating head type with seal strips that directed the water flow into the bundle to prevent by-passing of the fluid between the bundle and the shell. High localized velocities exist in the vicinity of the seal strips and contributed directly to the vibration problem. The tube natural frequency for various baffle spacings was measured at the vibration point and a gap velocity at the critical section of the bundle was estimated. A correlation was then made with these parameters and the fluidelastic excitation theory. A discussion of the velocity profile through the heat exchanger is included.