The general objective of this thesis is to contribute to the recognition of universal
patterns in wall-bounded adverse pressure gradient turbulent flows. For this purpose, the
experimental work has been carried out towards further understanding of this class of
flows, especially when the pressure gradient is increasingly adverse. Adverse pressure gradient turbulent flows and subsequent flow separation from a
plane or curved wall are encountered frequently in engineering applications in both
internal and external flows. Common examples of such internal flows can be seen in
diffuser flows in turbomachinery applications, in the flow passages of vehicles and
appliances, and in the flow passages inside a confining structure during a fire. Some
examples of adverse pressure gradient external flows are, the flow over an aerofoil, a
fuselage or a passenger car. In both internal and external cases, separation causes
momentum and energy losses, and due to the complexity of the resulting flow physics,
flow prediction becomes difficult for design purposes or performance optimisation. In
most cases, turbulent separation reduces performance efficiency. There is a definite lack
of turbulence data in the literature for adverse pressure gradient flows with and without
separation. Hence, thorough experimental investigation is valuable in developing a
fundamental understanding of such complex turbulent flows leading to practical
turbulence modelling.