Flank angle

Elastic solutions are often available for notches with small flank angles and small root radii. In the limit of zero root radius, the notch will be equivalent to a crack, i.e.. 

Another method to reduce the screw contact area is to use flat slanted flight flanks, i.e., a trapezoidal flight geometry see also Fig. 8.4(b). If the flight flank angle is 45°, the screw contact area in the flat plate model becomes ... 

Figure 8.88 shows the smallest values of the slot flank angle for which the inequality above is satisfied. 

As Fig. 8.88 indicates, the slot flank angle must be increased as the ratio of flight width to slot width decreases. When the slot width is twice the flight width, the slot flank angle has to be 90° to maintain full wiping. As a result, this will be the smallest value of the width ratio that will be practical. The preferred range of the flight to slot width ratio is from 1 1 to 3 1. 

Minimum slot flank angle for flight helix angle of 45°... 

Leakage through the tetrahedron gap causes interscrew material transfer. In fact, it is the only leakage flow that causes interscrew transfer. The tetrahedron gap increases when the flight flank angle is increased. Janssen, Mulders, and Smith [16] developed an empirical formula for the leakage flow through the tetrahedron gap ... 

This relationship allows the determination of the throughput pressure relationship for the filled length of a CICT extruder as a function of viscosity and machine geometry, Experimental verification with Newtonian fluids [15] has shown this relationship to be accurate to about 5 to 10%. Figure 10.34 shows the dimensionless output V as a function of flight flank angle when the dimensionless pressure drop AP = 1E4. 

Dimensionless output versus the flight flank angle... 

Clearly, the effect of calender clearance Is similar to the effect of flight flank angle. The effect of the radial flight clearance Is shown in Fig. 10.36 when AP° = 1E4. 

Longitudinal specimens from 1.09 mm (0.043 in.) annealed sheet, with an ultimate tensile strength of 955 MPa (138.5 ksi) and tensile yield strength of 915 MPa (132.8 ksi). Stresses are based on net section 3600 cydes/mln. Spedmens had 11 mm (0.448 in.) gross width, 7 mm (0.300 in.) net width, 0.5 mm (0.022 in.) root radius and 60° flank angle, and were as machined, edges polished with emery paper. 

Peterson approach represented a simplification of the original Neuber one [3] of 1937. Neuber, studying V notches having flank angle

effective notch factor flower than the theoretical one k, and linked to this last by the equation... 

In the plastic regime (grooving), the coefficient of friction (COF) of SLS glass increases with the indenter flank angle ft (Li, Shapiro and Li, 1998). 

Flank pain Pain in the side of the trunk between the right or left upper abdomen and the back (costovertebral angle). 

The H atom flanked by the two 0=0 groups in (22) exhibits hardly any more acidic character than the analogous one in the corresponding hydrocarbon. The different behaviour of (22) stems from the fact that after proton removal, the carbanion s lone pair would be in an sp3 orbital more or less at right angles to the p orbitals on each of the adjacent carbonyl carbon atoms (cf. p. 259) no sp3/p overlap could thus take place, consequently there would be no stabilisation of the -ve charge through delocalisation, and the (unstabilised) carbanion does not, therefore, form. 

The Sn structure84 87 again contains at least one long bond (208-211 pm) that is flanked by two short bonds (203-204 pm) with large enclosed torsion angles of 137 and 141° - reminiscent of S7 (Figure 27). 

The largest of all isolated Era moieties characterized by an X-ray structure is S20, which contains the unique ring structure shown in Figure 33.83>88>90>93 Unexpectedly, for an even-membered homocycle this S20 contains two long bonds at 210 pm that are flanked by short bonds (202 pm) and smaller enclosed torsion angles of 66° (see before S7, S9, Sn and S13). The long bond may also be responsible for the low-thermodynamic stability of dissolved S20. 

The more residues there are in an arc, the greater the turn of the polypeptide chain (Fig. 12). Two-residue arcs change the chain direction by 90-120°, three-residue arcs by 90-180°, four-residue arcs by 160-180°, and five- and six-residue arcs by 180°. For two-, three-, and four-residue arcs, the value of the turn-angle depends on the size of the side chains of the /Fstrands flanking the arc (in the 1B3 and 2B1 positions). 

The constraint that the tip of one screw element wipe the flank of its mate in self-wiping, corotating twin-screw extruders leads to a unique relationship for the shape of the screw channel (Booy, 1978,1980). Figure 13 is an isometric view of this channel and Fig. 14 is a cross section of the channel in a plane that is perpendicular to the plane which defines the helix angle. Figure 14 shows the actual shape of the channel, which is described by the following expressions ... 

The central seven-membered ring of the TCAs imposes a 120° angle between the two flanking aromatic rings, in contradistinction to the flat ring system present in phenothiazine type neuroleptics (p. 237). The side chain nitrogen is predominantly proto-nated at physiological pH. 

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