Published online by Cambridge University Press: 04 July 2016
Measurements of oscillatory derivatives made in various tunnels at the NPL over the past few years have indicated that slotted walls, as used in high-speed tunnels, may give rise to large interference effects on damping derivatives. Other workers in this field, notably in America, have also observed interference effects both with solid and with slotted walls. This paper presents the available evidence, so that those making similar measurements may be aware of the effects.