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The application of T-junction has already been extended from the petroleum engineering to the emerging advanced thermodynamic cycles. How a T-junction, as a separator in an emerging thermodynamic cycle, affects the cycle efficiency is discussed in this paper. Firstly, based on the Eulerian method, parametric studies on the local pressure drop coefficients are conducted and two new local pressure drop (LPD) coefficients are predicted in this paper. Then, the effects of pressure drop on a composition adjustable organic Rankine cycle efficiency is analyzed. In the process, a composition adjustable organic Rankine cycle with zeotropic mixtures R245fa/R123 is chosen to calculate the effects of pressure drop on thermodynamic cycle efficiency. The quality of the outlet of the evaporator is assumed as 0.7, and the composition ratio as 0.6/0.4. The results show that the pressure variation of T-junction affects the adjustable organic Rankine cycle efficiency, and reasonable phase separation ratio can improve the thermodynamic cycle efficiency. The pressure drop could cause composition diffusion. In addition, two new local pressure drop coefficients are obtained. And the results demonstrate that K12J declines slowly with the increases of density ratio (ρ2/ρ1) and decreases with the increases of mass fraction of taken off (F). K13J shows an obvious trend with diameter ratio (d3/d1) and F. This work could push the research of T-junction as a separator in the adjustable organic Rankine cycle, Sí

Vertical profiles of local pressure, horizontal profiles of net vertical solid mass flux, and residence time distributions (RTD) of the solid phase are experimentally assessed in the riser of a small scale cold circulating fluidized bed of 9 m high having a square cross section of 11 cm × 11 cm. Air (density 1.2 kg/m 3 , dynamic viscosity 1.8 × 10 −5 Pa s) and typical FCC particles (density 1400 kg/m 3 , mean diameter 70 μm) are used. The superficial gas velocity is kept constant at 7 m/s while the solid mass flux ranges from 46 to 133 kg/m 2 s. The axial dispersion of the solid phase is found to decrease when increasing the solid mass flux. Simultaneously, 3D transient CFD simulations are performed to conclude on the usability of the eulerian–eulerian approach for the prediction of the solid phase mixing in the riser. The numerical investigation of the solid mixing is deferred until later since the near-wall region where the solid phase downflow and mixing are predominant is not well predicted in spite of well-predicted vertical profiles of pressure.