Convected Jeffreys model

Shearing flows of the convected Jeffreys model. The convected Jeffreys model [6] or Oldroyd s B-fluid [54] is given by,... 

Indicating that the convected Jeffreys model gives a constant viscosity and first normal stress coefficient, while the second normal stress coefficient is zero. 

Develop expressions for the elongational viscosities fji and fj2 for steady shearfree flows of a convected Jeffreys model. Comment how this expression compares with experiments. 

An example of (a) is the convected Jeffreys model or Oldroyd B model " ... 

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