Point relaxation

Crimp. The tow is usually relaxed at this point. Relaxation is essential because it gready reduces the tendency for fibrillation and increases the dimensional stabiUty of the fiber. Relaxation also increases fiber elongation and improves dye diffusion rates. This relaxation can be done in-line on Superba equipment or in batches in an autoclave. Generally saturated steam is used because the moisture reduces the process temperatures required. Fiber shrinkage during relaxation ranges from 10 to 40% depending on the temperature used, the polymer composition used for the fiber, and the amount of prior orientation and relaxation. The amount of relaxation is also tailored to the intended apphcation of the fiber product. 

Components of dong quai may be capable of relaxing smooth muscle of visceral organs, including the intestines and uterus, via calcium channel blockade (Walker et al., 1998). The water-soluble, nonvolatile extract causes uterine stimulation, while the alcoholic extract (an essential oil with a high boiling point) relaxes the uterus (Huang, 1993). This relaxation may help reduce the pain associated with menstrual cramps (Johns, 1996). 

Point relaxation is best explained by assuming equal constant mesh widths Ax = Ay. Then, Equation 7-16 can be rewritten in the form... 

POINT RELAXATION BEGINS DO 400 NSWEEP=1,200 IF(MOD(NSWEEP,10).NE.O) GO TO 170 WRITE(, 155) NSWEEP WRITE(4,155) NSWEEP... 

Finally, there is the issue of vectorization, also referred to as scalar vs. parallel computing. Serial computers execute instructions sequentially, in specific order parallel machines execute multiple instructions simultaneously. Often, different flow domains are apportioned to different machines, and message passing interfaces must be designed so that these domains communicate with each other in an optimal way that minimizes computation time. Point relaxation gave way to line methods when serial computers were... 

Write a point relaxation program to solve the planar isotropic equation 5(k(x,y)5P/5x)/5x -l-9(k(x,y)cP/ )/ = 0. Assume solid walls at top and bottom, and high and low constant pressures at the left and right. Initialize the code with P = 0, and other functions show that convergence to a unique solution is independent of the function. Run this program for uniform permeabilities and show that pressures decrease linearly with x. 

W. Brown and S. Stepanek. Dynamic behavior in concentrated poly styrene/cyclohexane solutions close to the -point. Relaxation time distributions as a function of concentration and temperature. Macromolecules, 25 (1992), 4359 363. 

---