This paper presents some recent results for flow-induced vibrations experiments conducted in single phase and two-phase cross-flow of Refrigerant 11. Examined here is the vibration response of a model heat exchanger tube array, of parallel triangular arrangement with a pitch-to-diameter ratio of 1.44. The primary intent of this paper is to present damping measurements as a function of homogeneous void fraction, and compare these with comparable results of other researchers who used a variety of modelling fluids. These results show that the two-phase damping follows a similar trend with respect to void fraction as that of others results, and when normalized by liquid mass ratio and a confinement function, the damping results agree well with other researchers' values. A comparison of the vibration response of a fully flexible bundle and single flexible tube in a rigid bundle is also presented. It was revealed that the fluidelastic stability threshold was the same for both cases in single phase flow, but was greatly delayed or absent in two-phase flow for the single flexible tube bundle.
展开▼
