Expansion force

Design Temperature of Outlet Piping - The design temperature of outlet piping from PR valves discharging to the atmosphere is normally ambient. However, autorefrigeration and need for brittle-fracture-resistant materials or thermal expansion forces should be examined if the release pipe is unusually long. 

If a fluid contained in a cylinder expands so that its pressure remains constant (e.g.9 saturated steam in contact with water), the work done is that of raising the piston, of area a, which supports a weight W just sufficient to keep the expansive force indefinitely near equilibrium. If s = distance of outward motion of piston work A = W. s = pa. s = p. as = p v, where Av is the increase of volume. 

The mixing can be performed isothermally and reversibly by sinking the apparatus in a constant temperature bath, and opposing the expansive forces of the gases by forces differing only infinitesimally from them, and applied to the piston rods. 

A waterside expansive force that can be caused by a sudden drop in steam pressure without a corresponding decrease in temperature (especially in a FT boiler). Or a furnace expansive force due to the ignition of highly inflammable gas, vapor or dust. Minor furnace explosions are called puffs, flarebacks, or blowbacks. 

When a shock wave travels in a solid wall from one end to the other, a compressive force is created at the front end of the shock wave. When the shock wave reaches the other end, a reflection wave is formed, which travels back in the reverse direction. This reflection wave forms an expansion force that acts on the wall. 

When a shock wave propagates from one end (A) to the other end (B) of a solid body, a compression force is exerted in the wake of the shock wave that acts within the solid body. The shock wave is reflected at B and becomes an expansion wavethat propagates towards A. An expansion force is then exerted in the wake of the expansion wave that travels back from B. This process is shown schematically in Fig. 9.6. 

Fig. 3.33 Expansive forces are created within the capillary structure during freezing.

If such shells were stored at elevated tempe-raturefin tropical countries or in the deep South of the United States), the low melting point areas would liquefy and, due to expansion, force their way out thru the threads of the booster cup... 

Baalow b estimate of expansive force, A Bbraud s coai-wesbiag oiachine, 95, B uiraiua e analyses or fuels, 0fo-Bassix R fl patent fuel, iu0-i03. bituminous coai, analyses of, 77.7 Boghead coal, 83-B ... 

Figure 12.1. The process of spray atomization. (A) Conventional atomization break up of a liquid film from the shear with surrounding air (B) UNICARB vigorous decompressive atomization produced by the expansive forces of the compressed carbon dioxide (C) RESS solute precipitation due to solution supersaturation followed by nucleation and spinodal decomposition.

The swelling mechanism is well established in rubbers (Flory, 1943). The expansion force generated by the solvent penetration is equilibrated by the entropic force linked to chain stretching. Little is known, in contrast, for the case of glassy polymers where plasticization effects are not sufficient to induce a devitrification. Swelling can be defined by... 

Fire seemed to have the surprising power to divide bodies into their ultimate parts and to reach the most intimate nature of Bodies. Boerhaave did not believe, however, that fire could destroy the ultimate particles or Elements themselves. In the second experiment, he used the effect of cold or the absence of fire to establish the existence of contractive force inherent in the particles of bodies. The constitution of bodies would then be determined by the action and reaction of the expansive force of heat and the contractive force of union ... 

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