Fabula 



At the time of the photographs of Fig. 10, 22 hours had passed since the 

 dispersal of the JlOO into mixing barrels. The master solution had been gently 

 stirred for 15 hours. In the other 7 hours, the master solutions were mixed 

 with the towing-tank water by a continuous-flow technique giving a 50:1 dilution, 

 with grid stirring to make the tank fluid homogeneous. After the photographs, 

 the tank was stirred again for 4-1/2 hours by continuous back and forth towing 

 of the grid by automatic switching. No changes in raggedness and noise resulted 

 from this stirring. The solution was left in the tank over a 7-day period and 

 then checked. No changes were found. Thus there is an extreme difference of 

 behavior of Polyox and JlOO solutions with respect to dependence of the signal 

 raggedness upon solution age. This difference is similar to their difference 

 with respect to the dependence of viscosity upon solution age. 



The variation of towing-tank solution viscosity with age was studied with a 

 Caraher, low -shear -rate viscometer (8). Figure 11 gives the relative viscosity 

 {t]^) measurements- of towing-tank solutions of P301B. The data are in three 

 groups, according to whether the total amount of polymer added is 2, 4, or 6 



SOLUTION AGE . day* 



Fig. 11 - Collected data of relative 

 viscosity versus solution age for 

 P301B solutions in the towing tank 



*The measurements are for wall shear rates of about 5 sec" ^ and the values 

 are believed to be near to the zero-shear-rate values (8). 



54 



