Gas generation pressure

The supersonic air induced into the air-intake is converted into a pressurized subsonic airflow through the shock wave in the air-intake. The fuel-rich gas produced in the gas generator pressurizes the combustion chamber and flows into the ramburner through a gas flow control system. The pressurized air and the fuel-rich gas produce a premixed and/or a diffusional flame in the ramburner. The combustion gas flows out through the convergent-divergent nozzle and is accelerated to supersonic flow. 

Substituting Eq. (3.68) into Eq. (14.9), one obtains the gas generator pressure in a steady-state condition as... 

Fig. 15.18 SFJ test results obtained with a command signal composed of two sine waves, showing that the generated thrust follows the applied command signals through the gas generator pressure and the ramburner pressure.

Initially, the reactors in the days of the early methanol and ammonia syntheses operated at approximately 1000 atmospheres or 15,000 psi. This, over the years, has been reduced to 12,000, then to 5,000 and then to 750 but presently the trend is back up toward 2,500 psi (Figure 12). It is likely that, when single line 5,000 or 10,000 ton per day plants are constructed, the optimum pressure will be in the range of 2,500 to 4,000 psi. The economics of pressure and size are all closely related to many factors such as capital investment, reactor size, synthesis gas generating pressure, interconnecting piping size, method of generating synthesis gas, and problems of maintenance. 

Coal of up to 8 mm grain size is withdrawn from a bin, screw-fed to a coal Iqck and continuously introduced through the side of the gasifier shaft. In the case of the HTW, the screw feeders deliver the feed pneumatically to the coal locks, which are then pressurized to the gas generator pressure. Steam and... 

In addition, gas-generated pressure impedes deep penetration of the structure. 

For this reason water in the soil matrix will flow more easily in a horizontal direction than vertically. Thus gas bubbles will tend to form and coalesce in a horizontal plane as water in the soil matrix is displaced in the preferential horizontal direction. As more bubbles accumulate in tire horizontal plane they link together, forming networks which result in open cracks or fissures within the soil matrix through which gas can flow with little resistance (see Figure 5.1). Gas migrates through these open cracks or fissures either by gas generation pressure (advective flow), diffusion or buoyancy and escapes to atmosphere via the gas well installation (or other preferential vertical route). 

The type and amount of blowing agent governs the amount of gas generated, the rate of generation, the pressure that can be developed to expand the polymer phase, and the amount of gas lost from the system relative to the amount retained in the cells. 

Fig. 3.32. Basic principles of HF-plasma SNMS. Vhf, PHrarethe HF generator frequency and power, respectively, PArthe plasma gas (Ar) pressure 7e and the electron and plasma gas temperatures, respectively. Hpi = n is the plasma e, Ar" ) density. Bo the...

Uneonfined vapour eloud explosion a large flammable gas or vapour-air eloud burns in free spaee with suffleient rapidity to generate pressure waves, whieh propagate through the eloud and into the suiTounding atmosphere. Sueh events are extremely rare. 

The pressures exerted by gases demonstrate molecular motion. Gases are collections of molecules, so the pressure exerted by a gas must come from these molecules. Just as the basketball In Figure 2J exerts a force when it collides with a backboard, moving gas molecules exert forces when they collide with the walls of their container. The collective effect of many molecular collisions generates pressure. 

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