Document Type : Article

**Authors**

Center of Excellence in Design and Optimization of Energy Systems (CEDOES), School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran

**Abstract**

Linear stability of a thixotropic fluid obeying the Moore model is investigated in pipe flow using a temporal stability analysis in which infinitesimally-small perturbations, represented by normal modes, are superimposed on the base flow and their evolution in time is monitored in order to detect the onset of instability. An eigenvalue problem is obtained which is solved numerically using the pseudo-spectral Chebyshev-based collocation method. The neutral instability curve is plotted as a function of the thixotropy number of the Moore model. Based on the results obtained in this work, it is concluded that the thixotropic behavior of the Moore fluid has a destabilizing effect on pipe flow

**Keywords**

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Transactions on Mechanical Engineering (B)

March and April 2018Pages 790-798