Spiral eccentrical spirals

Figure 5.9. Eccentric spiral pattern on a (0001) face of SiC, due to a supersaturation gradient over the surface [13]. The spiral center is indicated by c, and the arrows a, b show the directions of eccentricity (where the white arrow refers to the center of the crucible, and the black arrow refers to the wall).

The mash is conveyed from the fruit mill to the press, and to and from the heat exchanger, by means of valveless eccentric spiral pumps, large impeller pumps or slow-running piston pumps. 

A scroll vacuum pump uses two interleaved Archimedean spiral-shaped scrolls to pump or compress gases (see Fig. 1.9). One of the scrolls is fixed, while the other orbits eccentrically without rotating, thereby trapping and compressing gases between the scrolls and moving it towards the outlet. 

Sunagawa,/. Narita, P. Bermema, and B. van der Hoek, Observation and interpretation of eccentric growth spirals,/. Crystal Growth, 42,1977,121-6... 

This patent contains a description of a screw mixer with eccentric, triple-flighted spirals. 

Not all bodies are capable of attaining steady motion with unsymmetrical bodies spiraling and wobbling may occur. For an oblate spheroid [12 p 144] of eccentricity and equatorial diameter a, the maximum drag force, for tending to 0, is ... 

Spirality, like flexibility and geometrical eccentricity, increases the entropy of melting. 

The core-sheath (c-s) configuration is adaptable because many different polymers may be applied as a sheath over a solid polyester core, thus giving a variety of modified surface properties while maintaining all the major fiber and textile properties of PET. An early patent by Shima and coworkers uses an eccentric core-sheath configuration to achieve spiral crimp in a yarn [67]. A recent patent by Chang and coworkers discloses the use of side-side or eccentric c-s bicomponent fibers to achieve a self-crimping yarn made from polytrimethylene terephthalate, where one component is a melt-blend of PTT with a small amount of polystyrene [68]. 

Fig. 21.9. Nonossifying fibroma. Well defined eccentric lytic lesion with a spiral fracture extending up the tibial diaphysis...

A spiral still, with three spirals in series, vertical axis, and eccentric movement, was proposed by Piazza and Rouzaut (1939) for the distillation of alcohol from wines. Results higher by 0.1% to 0.2% compared to those with the ebullioscope were obtained. Using the apparatus Rouzaut (1939) was able to obtain all of the alcohol in 7 minutes. Hanak (1932) proposed an all-glass apparatus which Colombier and Clair (1936) have adopted for the distillation of wines. The latter investigators claim results from 0.1% to 0.2% higher than with the usual apparatus. 

For design, pure compression strength is a hypothetical condition since almost always there wiU be moments present due to various reasons. For this reason, AASHTO LRFD S.7.4.4 limits the nominal axial load resistance of compression members to 85% and 80% of the axial resistance at zero eccentricity, P , for spiral and tied columns, respectively. 

The explanation for this is that the pressure build-up in the peripheral direction of the piston (at an eccentricity equal to 0.5) is so large that the negative effects, which arise from a pressure difference across the spiral groove bearing, are compensated. 

I This situation shows the normal operation of the spiral groove bearing. The peripheral velocity u is responsible for the pressure build-up in the gap. It can be said that this type of bearing is stable (has positive stiffness) for every value of eccentricity. 

III This is the most interesting situation. Here, a piston that is provided with spiral grooves is situated eccentrically in a... 

The smooth section, which serves as a "seal", functions as a radial plain bearing. It is known that this type of bearing always tends to instability for relative values of eccentricity below 0.5. The two adjacent spiral groove sections must have sufficient positive stiffness to compensate the negative effect of the smooth section, thus making the whole construction stable. 

Fig. 4.2a-e. A 73-year-old male patient with renal cell carcinoma, diabetes mellitus and cardiovascular comorbidity. Multiplanar reformat (MPR) in the coronal plane from a pre-interventional multislice spiral CT depicts an eccentric 3.6-cm tumor of the right kidney (arrows) (a). The patient was considered to be at high risk for surgery. Because of the size of the hypervascularized tumor, a tumor embolization was performed prior to RF ablation (b,c). An umbrellashaped RF probe was introduced percutaneously via a lateral approach (d). Four months after RFA the axial CT image shows no contrast enhancement in the tumor area (arrows), corresponding to complete tumor necrosis (e). A sufficient safety margin without contrast enhancement is visible... 

A pair of neutron stars, with initial separation 500 km, would spiral together in a matter of minutes, whereas a neutron star would take more than a decade to spiral into a super-massive black hole (10 Mg) from 5 times the radius of the black hole. The decay time is shorter for eccentric orbits. 

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