Cord geometry

The pneumatic tire has the geometry of a thin-wallcd toroidal shell. It consists of as many as fifty different materials, including natural rubber and a variety ot synthetic elastomers, plus carbon black of various types, tire cord, bead wire, and many chemical compounding ingredients, such as sulfur and zinc oxide. These constituent materials are combined in different proportions to form the key components of the composite tire structure. The compliant tread of a passenger car tire, for example, provides road grip the sidewall protects the internal cords from curb abrasion in turn, the cords, prestressed by inflation pressure, reinforce the rubber matrix and carry the majority of applied loads finally, the two circumferential bundles of bead wire anchor the pressnrized torus securely to the rim of the wheel. 

Bolton, R. G. Boddy, L. (1993). Characterisation of the spatial aspects of foraging mycelial cord systems using fractal geometry. Mycological Research, 97, 762-8. 

Holsheimer, J., Struijk, J.J., and Tas, N.R. Effects of electrode geometry and combination on nerve fibre selectivity in spinal cord stimulation. Med. Biol. Eng. Comput. 1995 33 676-682. 

Ropes and cords are made in long lengths and cut up for particular uses. Reflecting this geometry, they are often called lines. In addition to the strictly one-dimensional forms, there are some others to be mentioned. Slings are circular forms made by... 

Table 8.4 Changes in fractal geometry of mycelial systems during interactions between Stmpharia caerulea and other cord-forming, saprotrophic basidiomycetes in trays of compressed soil. Data from [61].

Rounding up tower diameter D to 3 ft. Note that the diameter is small for trays as the tower is used for laboratory testing. Weir length L is the cord length in a circle, while weir width is the rise as shown in Figure 12.17. From geometry, there is a relationship between arc area (Aj), rise (the same as downcomer width Wd) and radius (r = D/2) ... 

Shaped breast beams as machine devices to increase or to decrease warp end and weft spacing in a centre part of a woven fabric have been suggested long time ago (e.g., Wever and Seel, 1899). However, if the shell geometry is a single shell like a helmet and not continuously curved like a corset fabric or a tire cord fabric, then there are two main drawbacks of this method ... 

The joint geometry of our samples surely implied the presence of spew fillets, being the shaft press-fitted into the hub. The external spew fillet was visible after the coupling and it was removed before the adhesive cure. The internal one was observed after the breaking of the joint, but the geometry of the sample made impossible to remove it. Indeed, according to the pin and collar test method, a cord shaped adhesive spew must remain in one of the collar ends (Abenojar et al., 2013). 

Some criteria are presented for evaluating the various tyre design theories that are based on the equilibrium shape of the sidewall and on the rolling contour of a tyre. Tyre failure types and the mathematical models by which they can be predicted by modem theories of mbber/cord fatigue are also described. A tyre design theory based on stress-strain optimisation of its elements is proposed as is a hierarchic system of complicated tyre models for calculation of stress-strain cycles. Influence of the cross-section geometry and of the iimer stmcture of the tyre on stress-strain cycles in the belt and bead of radial tyres is investigated. 21 refs. 

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