• Article  

      Determination of the rheological parameters of self-compacting concrete matrix using slump flow test 

      Neophytou, Marina K. A.; Pourgouri, S.; Kanellopoulos, A. D.; Petrou, Michael F.; Ioannou, I.; Georgiou, G.; Alexandrou, Andreas N. (2010)
      The classification of a concrete mixture as self-compacting (SCC) is performed by a series of empirical characterization tests that have been designed to assess not only the flowability of the mixture but also its segregation ...
    • Article  

      Flow instabilities of Herschel-Bulkley fluids 

      Alexandrou, Andreas N.; Menn, P. Le; Georgiou, G.; Entov, V. (2003)
      We investigate numerically the interactions of two-dimensional jets of Bingham plastic and Herschel-Bulkley fluids with a vertical surface at a distance from the die exit. This problem simulates the early stages of filling ...
    • Article  

      On the early breakdown of semisolid suspensions 

      Alexandrou, Andreas N.; Georgiou, G. (2007)
      Semisolid materials are suspensions of metal alloys which are processed while in a mushy state. In this state, the suspensions behave as viscoplastic materials with time-dependent material properties. During processing, ...
    • Article  

      Parameter estimation for semi-solid aluminum alloys using transient experiments 

      Alexandrou, Andreas N.; Georgiou, G.; Tonmukayakul, N.; Apelian, D. (2006)
      A rotating vane-cup rheometer is used to determine the rheological properties of semi-solid slurries, and a procedure is established for characterizing the rheology with emphasis given to the proper and self-consistent ...
    • Article  

      Predictions of structure breakdown, buildup and shear banding in semisolid suspensions 

      Alexandrou, Andreas N.; Constantinos, N.; Georgiou, G. (2008)
      When SSM material is subjected to a sudden transient the rate of buildup (aging) is negligible compared to the rate of breakdown (shear rejuvenation). While this is generally true, due to prolonged processing or the geometry ...
    • Article  

      Shear rejuvenation, aging and shear banding in yield stress fluids 

      Alexandrou, Andreas N.; Constantinou, N.; Georgiou, G. (2009)
      The purpose of this work is to simulate shear rejuvenation and aging effects in shear thinning yield stress fluids in a typical rotational rheometer and to provide a common framework to describe the behavior of yield stress ...
    • Article  

      Squeeze flow of thixotropic semisolid slurries 

      Alexandrou, Andreas N.; Florides, G. C.; Georgiou, G. (2014)
      An essential element for the integration of a semisolid process in the production of complex commercial components is the availability of accurate mathematical and computational tools that could describe both the rheological ...
    • Article  

      Wall shear rates in circular couette flow of a Herschel-Bulkley fluid 

      Chatzimina, M.; Georgiou, G.; Alexandrou, Andreas N. (2009)
      The objective of this work is to study quantitatively the errors introduced by the standard Newtonian and power-law assumptions used in the determination of the material properties of viscoplastic fluids from circular ...