Carreau—Yasuda model parameters

C.1 Carreau-Yasuda Model Parameters from Regression Analysis. Use either Solve in Excel or the IMSL subroutine RNLIN (Example 2.1) to find the Carreau-Yasuda model parameters [Eq. 2.8 with (n — l)/2 replaced with (n - )/a] for LLDPE at 170 °C (viscosity data are given in Appendix A.3) and compare the results with those given in Table 2.1. 

If some or all of this curve is present, the models used to fit the data are more complex and are of two types. The first of these is the Carreau-Yasuda model, in which the viscosity at a given point (T ) as well as the zero-shear and infinite-shear viscosities are represented. A Power Law index (mi) is also present, but is not the same value as n in the linear Power Law model. A second type of model is the Cross model, which has essentially the same parameters, but can be broken down into submodels to fit partial data. If the zero-shear region and the power law region are present, then the Williamson model can be used. If the infinite shear plateau and the power law region are present, then the Sisko model can be used. Sometimes the central power law region is all that is available, and so the Power Law model is applied (Figure H. 1.1.5). 

The Bird-Carreau-Yasuda Model. A model that fits the whole range of strain rates was developed by Bird and Carreau [7] and Yasuda [72] and contains five parameters ... 

Figure 4 illustrates how the Carreau-Yasuda model meets the shear viscosity data of Fig. 2. A non-linear fitting algorithm (i.e. Marquardt-Levenberg) was used to obtain the parameters given in the inset. As can be seen the fit curve provides a shear viscosity function that corresponds reasonably well with experimental data so that the high shear behavior is asymptotic to a power law and the very low shear behavior corresponds to the pseudo-Newtonian viscosity po- The characteristic time X (56.55 s) can be considered as the reverse of a critical shear rate (i.e. = Yc = 0.0177 s ) that corresponds to the intersection between the high shear power...

During the experiments, the solid concentration was increased to 20% by volume. Except for suspensions with plastic particles, the suspensions showed a Newtonian behavior up to volume contents of 15 %. Suspensions with glass beads and s = 0.2 as well as all examined suspensions with plastic particles showed a shear thinning behavior. Considering the non-Newtonian behavior of these suspensions in the calculation of the time steady flow based on Eqs. (5.9-5.21), the viscosity of the suspension had to be described by a model depending on the deformation speed y. A Carreau-Yasuda model according to Eq. (5.52) fitted well to measurements carried out with a Couette system. The parameters Hq, a, n, and X were determined by the rheological measurements. 

The Yasuda model (Yasuda et al., 1981) is a modification of the Carreau model with one additional parameter a (a total of five parameters) ... 

The empirical Carreau-Yasuda (or, sometimes, Carreau-Yasuda-Elbirli) model contains two additional parameters and is extensively used to correlate melt data ... 

We investigate the influence of different destabilizing parameters on the primary breakup of non-Newtonian jets to analyze the primary breakup process. During our research our numerical simulations have constantly been improved. The more accurate Carreau-Yasuda viscosity model was implemented in FS3D and validated against experimental data. The earlier simulations used aqueous PVP solutions as model fluids due to their status as model fluid inside SPP 1423 and the good... 

Modeling the shear viscosity function of filled polymer systems by combining two Carreau-Yasuda equations the curve was calculated with the following model parameters Tioj = 8x10 Pa.s X = 500 s Aj = 1.9 = 0.4 rioj = 3x10 Pa.s - O l s = 3 Wj = 0.33. 

By combining two Carreau-Yasuda equations, an eight parameter model is obtained that would meet all the likely typical features of the shear viscosity behavior of filled polymer systems. 

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