We present here phase equilibria calculations of polyethylene solutions in different solvents as obtained with two versions of the SAFT equation of state, soft-SAFT and PC-SAFT. The objective of this work is twofold: to check the accuracy of the soft-SAFT equation in providing reliable polymer solutions behavior and to propose a methodology from which systematic studies on polymer solutions can...

We have developed a “global” crossover (GC) statistical associating fluid theory (SAFT) equation of state (EOS) for associating fluids that incorporates nonanalytic scaling laws in the critical region and in the limit of low densities, F f 0, is transformed into the ideal-gas equation EOS. Unlike the crossover SAFT EOS developed earlier, the new GC SAFT EOS contains a so-called kernel term and ...

The SAFT-VRX equation of state combines the SAFT-VR equation with a crossover function that smoothly transforms the classical equation into a nonanalytical form close to the critical point. By a combinination of the accuracy of the SAFT-VR approach away from the critical region with the asymptotic scaling behavior seen at the critical point of real fluids, the SAFT-VRX equation can accurately d...

In B-mode imaging, lateral resolution is impeded by the size and shape of the ultrasound beam used to create the image. For improved lateral resolution, a focussing method that utilises a beam model calculated using the Fraunhofer far field approximations to enhance the Synthetic Aperture Focussing Technique (SAFT) is proposed. The Beam Model Weighted Synthetic Aperture Focussing Technique (BMW...

In previous work, we developed the crossover SAFT–VR equation of state (SAFT–VRX) for pure fluids by following the crossover approach proposed by Kiselev. The SAFT–VRX equation was shown to be very accurate in the prediction of PVT and phase behaviour for both nonassociating and associating fluids. In particular, simple expressions for the potential model parameters for the n-alkane homologous ...

In this work, we extend the pure fluid crossover statistical associating fluid theory (HRX-SAFT) equation of state (EOS) (Kiselev et al., Fluid Phase Equilib. 2001, 183-184, 53) to fluid mixtures of polar and associating components. HRX-SAFT incorporates non-analytic scaling laws in the critical region and is transformed into the analytical, classical HR-SAFT EOS far away from the critical poin...

The Special Affine Fourier Transformation or the SAFT generalizes a number of well known unitary transformations as well as signal processing and optics related mathematical operations. Shift-invariant spaces also play an important role in sampling theory, multiresolution analysis, and many other areas of signal and image processing. Shannon’s sampling theorem, which is at the heart of modern d...

The molecular-based SAFT equation of state has proven to be very versatile in the prediction of fluid phase equilibria. However, in common with all analytic equations of state, SAFT exhibits classical behavior in the critical region rather than the nonanalytical, singular behavior seen in real fluids. As a result, accurate agreement over the whole phase diagram cannot be obtained and must be lo...

INTRODUCTION New fast and efficient multi-channel ultrasonic echo measurement systems are currently introduced for practical applications in NDT-CE [ 1, 2]. The acquired multi-offset data are currently processed and imaged by the synthetic aperture focussing technique (SAFT, see e.g. [ 3, 4]). The application of SAFT, which is closely related to the seismic Kirchhoff migration method, is succes...