“Everything flows?”: elastic effects on startup flows of yield-stress fluids

It is now 30 years since Barnes and Walters published a provocative paper in which they asserted that the yield stress is an experimental artifact. We now know that the situation is far more complicated than understood at the time, and that the mechanics of the solid material prior to yielding must be considered carefully. In this paper, we examine the response of a well-studied “simple” yield-stress material, namely a Carbopol gel that exhibits no thixotropy, and demonstrate the significance of the pre-yielding behavior through a number of elementary measurements

Development of statistical process control (SPC) matlab-based software for automotive industries application

This project is motivated by an interest in promoting the use computer-based statistical process control (SPC) in manufacturing sector specifically for automotive industries in Malaysia. The use of computer-based SPC is essential in quality function. They are capable to perform various operations or tasks very accurately at fast speeds. SPC techniques are simple statistical techniques to help identify process problems and it can be implemented as simple as analyzing data and plotting charts. However, the development of SPC in Malaysian small and medium-sized enterprises (SMEs) is found lacking because they remain to use traditional SPC techniques which the data are calculated and analyzed manually. Consequently, manual work on traditional SPC has focused on particular limitations; with only little quality faults are detectable, time-consuming and burdensome. This paper highlights the results of an effort to design the SPC computer-based system for conducting simple statistical analysis. The system named as MagNa version 1.0 MATLAB-based software, which is able to offer more benefits to the Malaysian SMEs specifically for automotive industries application

Issues in the flow of yield-stress liquids

Yield-stress liquids are materials that are solid below a critical applied stress and flow like mobile liquids at higher stresses. Classical descriptions of yield-stress liquids, which have been the basis for asymptotic and computational studies for five decades, are inadequate to describe many recent experimental observations, and it is clear that the time dependence of microstructure must be taken into account in the description of many real yield-stress liquids