Inside radius/thickness ratio

The main influencing elements on this empirical k factor are the inside radius, material thickness, and the mechanical properties of the metal. The larger the rit ratio, the closer k is to 0.5. The larger the yield and tensile strength, the closer k is to 0.5. 

Fig. 8.13 illustrates the manner in which stress concentrates in inside corners by plotting the ratio of the inside radius (R) to the wall thickness (WT against the stress concentration factor. At ratios below 0.5, the stress concentration factor rises dramatically. At the ratio of 0.25, it has reached 2.25. That should be regarded as an absolute minimum. Below 0.25, the stress concentration factor reaches toward astronomical levels. Even a little radius is better than none at all. In addition to the reduction in stress concentration factor, radiused corners also improve the flow of plastic in the mold resulting in a more uniform melt and a shorter molding cycle. 

Ratio of inside radius/nominal wall thickness... 

FIGURE 6.14 Striation thickness reduction function in rotational Couette flow (RCF) for various ratios of the outside to the inside radius. Newtonian and power-law fluids do not exhibit any significant difference. 

Akyurtlu et al. [1988] have found that when B becomes depleted inside the membrane matrix, the reaction conversion is very sensitive to the annular space in a CNMMR (see Figure 10.20). The average conversion of at the reactor outlet increases as the radius ratio X(s / 2 3) increases. The rate of increase is particularly rapid as X approaches 1. This means that when the annular liquid region becomes small, the reaction conversion is high for a constant throughput and a constant membrane thickness. In the same study, a parameter y was defined as... 

With polyacrylamide adsorbed onto modified glass beads, a "hydrodynamic Isotherm" (variation of the thickness with the bulk concentration) could not be obtained through measurements of the suspension viscosity, since at low bulk concentration, adsorption Induces bead aggregation ( ). Table I presents the plateau values of for different samples, and they consistently overestimate the radius of gyration value by about 70 It Is therefore clear that, because of strong lateral excluded volume Interactions, the chain loops are stretched away from the surface. Moreover, Table I also shows that the ratio between the mean monomer density at the surface and in solution (Inside the coll) veurles between 20 and 30. Thus, despite the excluded volume Interactions, one observes that the... 

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