Segel-Pochettino geometry

Axial Motion Between Coaxial Cylinders (Segel-Pochettino Geometry)... 

With a similar principle, the apparatus of Chompff uses Segel-Pochettino geometry if of Fig. 5-1) with a thin foil to contain the viscoelastic liquid between the cylinders. The displacement of the inner cylinder is measured by a differential transformer and the force on the outer cylinder by a ferroelectric ceramic transducer. The frequency range is from 1 to 2500 Hz, and good temperature control is provided over an extremely wide range. The moduli G and G" arp obtained as in equations 19 and 20, with the form factor b specified by equation 13. A related apparatus with continuous recording at constant frequency has been described by Date. ... 

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