Orifice

Gaseous fuels. Gas burners can be diffusion flame burners or pre-aeraled burners. Diffusion flame burners may be relatively simple, with fuel gas burning at an orifice in the presence of... 

The viscosity is determined by measuring the time it takes for a crude to flow through a capillary tube of a given length at a precise temperature. This is called the kinematic viscosity, expressed in mm /s. It is defined by the standards, NF T 60-100 or ASTM D 445. Viscosity can also be determined by measuring the time it takes for the oil to flow through a calibrated orifice standard ASTM D 88. It is expressed in Saybolt seconds (SSU). 

Certain calibrated orifice instruments (Engler-type) provide viscosity measurements at temperature lower than pour point. This is possible because the apparatus agitates the material to the point where large crystals are prevented from forming whereas in other methods, the sample pour point is measured without agitation. 

Operating conditions all gas lift valves apart from the bottom orifice valve are closed. The energy to the system is delivered by a compressor. The performance of the system is monitored by observing flowrates and the casing and tubing pressures. 

A jet emerging from a nonciicular orifice is mechanically unstable, not only with respect to the eventual breakup into droplets discussed in Section II-3, but, more immediately, also with respect to the initial cross section not being circular. Oscillations develop in the Jet since the momentum of the liquid carries it past the desired circular cross section. This is illustrated in Fig. 11-20. 

Fig. n-21. Surface tension as a function of age for 0.05 g/100 cm of sodium di(2-ethylhexyl)sulfosuccinate solution determined with various types of jet orifices [109]. 

The physical structure of a surface, its area, morphology and texture and the sizes of orifices and pores are often crucial detemrinants of its properties. For example, catalytic reactions take place at surfaces. Simple... 

For effusion through an orifice Graham drew the following conclusions. 

As a consequence of these simple deductions, Graham s experiments c effusion through an orifice came to be regarded as one of the earliest direct experimental checks on the kinetic theory of gases. However, a closer examination of his experimental conditions reveals that this view is mistaken. As mentioned earlier, his orifice diameters ranged upwards from 1/500 in., while the upstream pressure was never very much less thai atmospheric. Under these circumstances the molecular mean free path len ... 

To obtain the necessary pressure on the lid, and for general protection when the bomb is being heated, the bomb is placed in a hea y metal case G, in which the collar E of the bomb rests in a circular recess at the top of G, and the base of A just appears through the bottom of G. The lid H of the case screws down over G, and has an orifice through which the pillar F of the bomb projects when H is screwed firmly down onto G. The bottom portion of G and the sides of H are made of hexagonal cross-section so that both can be firmly held with suitable tools whilst H is being screwed down and is thus thrusting the lid C of the bomb firmly down onto the base A. 

Fig. II, 55, 3 depicts a ground joint with glass hooks, to which light springs may be attached. Figs. II, 55, 4 and II, 55, 5 are drip cones for condensers and the like the latter is generally employed for joints larger than 29 mm. in diameter, the orifice being reduced to about 18 mm. Fig. II, 55, 6 is a double-cone joint in which two cones, e.g., B19 and 524, are made like a single joint this is valuable as it saves the use of an adapter.

Line-of-sight from Inlet tube to skimmer orifice... 

Ions and neutral molecules headed for skimmer orifice, drawn mainly by the vacuum system... 

The flow of droplets is directed through a small orifice (Skimmer 1 Figure 12.1) and across a small region that is kept under vacuum by rotary pumps. In this region, approximately 90% of solvent and injected helium is removed from the incipient particle beam. Because the rate of diffusion of a substance is inversely proportional to its molecular mass, the lighter helium and solvent molecules diffuse away from the beam and are pumped away. The heavier solute molecules diffuse more slowly and pass through the first skimmer before they have time to leave the beam the solute is accompanied by residual solvent and helium. 

For a plasma temperature of 8000 K and N(,= lO Vml, A, is about 0.0006 mm, which is very much smaller than the 1-mm sampler orifice, so ions can pass through easily. Hot gases from the plasma impinge on the edges of the sampler orifice so deposits build up and then reduce its diameter with time. The surrounds of the sampler orifice suffer also from corrosive effects due to bombardment by hot species from the plasma flame. These problems necessitate replacement of the sampler from time to time. 

The liquid sample flows into the nozzle and coats the inside walls. The sample stream arrives at the orifice (the nozzle outlet is about 0.01 cm diameter), where it meets the argon stream and is nebulized. 

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