Abstract
The technique to measure planar elongation viscosity from both mechanical and optical measurement by using two-dimensional opposing flow has been developed. It was clarified a transitional change in flow birefringence and nozzle reaction force at start-up flow. And, the validity of this technique was considered from the experimental results. Transient behavior of the nozzle reaction force and flow birefringence are simultaneously measured by using new system. They show almost corresponding qualitatively. It indicates that this technique can evaluate planar elongation viscosity for not only fluid that obey stress-optical rule and has strong birefringence but also fluid has flow birefringence property.
