Rheology data analysis software
Rheology data analysis software
Keywords: Bohlin Instruments, Rheology, Software, Data analysis
The RHEA™ Software is described as a user-friendly analysis package that has been specifically developed for rheologists who require rapid and easy to use viscoelastic analysis procedures.
RHEA includes a time temperature superposition package (TTS) with automatic shifting routines. Master-curves of stiffness or compliance information, in either the time or frequency domains, can be easily generated from dynamic or transient data types produced at different isotherms. The shift factors can be related using the Williams-Landel Ferry equations (WLF). The TTS package has several applications. For example, in the plastics industry, dynamic mechanical data are used for understanding the complex behaviour of polymers over a wide range of frequency or stiffness. Typically, a master curve can reportedly be generated covering more orders of magnitude in the frequency or time domain than would be possible using the rheometer's experimental operating range.
Additionally, RHEA is said to convert dynamic mechanical data (G ' G"vs. w) from the frequency domain to the time domain, G(t) and J(t) and vice-versa. The shifted master curves are fitted using a modified non-linear Marquadt-Levenburg least squares optimisation routine. This is followed by a numerical analysis calculating the discrete relaxation and retardation spectra. The software then numerically optimises the number of relaxation/retardation modes used in the analysis, thereby generating a discrete spectrum of relaxation or retardation times. A maximum of 32 relaxation modes can be calculated for the data sets.
The RHEA software is stated to be directly compatible with any Bohlin windows software version and operates on Windows 95, Windows 98 and Windows NT systems.
Details available from Bohlin Instruments. Tel: +44 (0)1285 644407; e-mail: mailto;lw@bohlin.co.uk; Web site: www.bohlin.co.uk
