Resonance tests on a helically wound heat exchanger

Experimental resonance tests were carried out in late 1977 on a boiler pod of Heysham 1 advanced gas-cooled reactor station. The tests were used to measure the vibration properties of the boiler in terms of its natural frequencies, mode shapes and damping levels. The dynamic behaviour of loosely supported boiler tubes was also investigated and the relative motion between the tube and support strap was measured. The results of these tests validated the finite element model used to predict the boiler's high cycle stress levels and wear rates from acceleration response measurements taken during the commissioning tests and the raising to power phase of station operation. (author)