Selected Research Projects
DTR’s principal research interests fall naturally into distinct categories.
Fundamental fluid mechanics
A long-standing interest in phenomena influencing wave propagation along one-dimensional ducts has focussed on the influence of unsteady skin friction on the walls of ducts. Dundee’s work in this area has led to the only method available worldwide for estimating the values of unsteady shear stress coefficients without the need for empirical coefficients. Initially, the methodology was restricted to short-lived events typical of pressure wave fronts in rail tunnels. Subsequently, it has been used to predict values of an empirical coefficient in a popular alternative model of unsteady friction that is widely used in analyses of water hammer in pipelines.
Wave propagation and sonic booms
Waves generated by high speed trains in sufficiently long slab track tunnels can cause loud sonic booms to propagate from tunnel portals into the surrounding environment. DTR’s research on this topic has benefited from a series of collaborative projects with Japanese Universities as well as from participation in a major European research project, Transaero.
Control
The operational control of tunnels, especially technical systems such as ventilation, is increasingly handled automatically. DTR seeks to improve the effectiveness of such systems by the use of predictive algorithms that are more reliable than conventional extrapolation algorithms. Work on this topic has progressed in collaboration with Sohatsu Systems Laboratory Inc in Japan.
Numerical analysis
DTR prides itself on the accuracy with which its numerical analyses solve the analytical equations used to represent tunnel airflows. In addition to being unusually accurate, the algorithms are robust and fast. Historically, much of this development has been undertaken at DTR and transferred to the university. In recent years, a project with the University of Tokyo has added academic rigour to practical understanding and is leading to improved methods of choosing numerical grids for unsteady flow analyses.