Dr Peter Richards, University of Auckland

Peter Richards is an Associate Professor in Mechanical Engineering at the University of Auckland. He obtained his bachelor’s degree from Reading University and his PhD at the Royal Military College of Science, Shrivenham. He emigrated to New Zealand in 1981, but has returned to the UK on research and study leave on several occasions, working at the Silsoe Research Institute and the University of Birmingham on wind engineering research, with particular emphasis on storm damage of low-rise buildings. He has served as Director of the UoA Yacht Research Unit, which for many years conducted a majority of the world’s wind tunnel testing of sails. In recent years he has made several trips to Nicaragua, installing small wind and solar energy systems with a UK charity, the Peace and Hope Trust. In 2014 he received the UK-US Fulbright- Lloyds of London Insurance Scholarship which supported his 5 month stay at Florida International University’s Wall of Wind facility working on improved testing techniques for modelling hurricane force winds. He is the author of more than 80 journal and 100 conference papers.

“Capabilities and limitations of large scale test facilities”

In recent years a number of large-scale test facilities have been constructed including the Insurance Institute for Business & Home Safety Wind Tunnel in South Carolina and FIU’s Wall of Wind. FIU’s 12-fan Wall of Wind (WoW) is the US’s first university research facility capable of simulating Category 5 hurricane winds. With 520 kW behind each 1.8m tall fan, the Wall of Wind can generate winds of up to 250 km/h. With a test section 4.5m high by 6m wide, the Wall of Wind allows researchers, businesses, government agencies and industry to test and analyse how structures and products perform in various hurricane conditions. Unfortunately replicating the effects of hurricane force winds is not just a matter of having enough power to generate very high wind speeds, the flow must also reproduce the important features of the unsteady flow. Not only does the turbulence create unsteady loads but it can also stimulate resonant responses in internal pressures or other systems. In addition the medium to small scale vortices in the flow are important in determining the curvature of the flow around a building or structure and hence can indirectly affect the wind loads. Regrettably it is almost impossible in any test facility to fully reproduce all of the features of strong winds and so it is necessary to understand what features must be simulated and what deficiencies can be compensated for by appropriate post-processing.

During 2014 the author spent 5 months at the FIU, observing and analysing data from this facility. One of the test cases used was a 1:5 scale model of the Silsoe 6m Cube.

This paper will address a number of issues which arise with such large-scale facilities, including: