Pipes gases, flow through

While plug flow is an idealization, fluid flow through long pipes, gas flow through packed beds under certain conditions, and some transfer line reactors may be regarded as plug flow systems as a reasonable approximation. 

The method is based on the international standard ISO 4053/IV. A small amount of the radioactive tracer is injected instantaneously into the flare gas flow through e.g. a valve, representing the only physical interference with the process. Radiation detectors are mounted outside the pipe and the variation of tracer concentration with time is recorded as the tracer moves with the gas stream and passes by the detectors. A control, supply and data registration unit including PC is used for on site data treatment... 

FIG. 6-26 Parameters for pressure drop in liqiiid/gas flow through horizontal pipes. (Based on Lockhatt and Maitinelli, Chem. Engr. Prog., 45, 39 [1.94.9],)... 

Gas flow through the compressor is measured by flow nozzles or other devices installed in the piping. Among the various devices are ... 

Annular Liquid flows in continuous annular ring on pipe W all, gas flows through center of pipe... 

As the air or gas flows through the blower system (piping/ ducts, filters, etc.), the movement causes friction between the flowing air/gas. This friction translates into resistance to flow, whether on the inlet (suction side) or outlet (discharge side) of the system in which the blower is a part and that creates the pressure drop (see Chapter 2, V. 1, 3 Ed., of this series) which the blower must overcome in order for the air/gas to move or flow. This resistance to flow becomes greater as the velocity of flow increases, and more energy or power is required to perform the required flow movement at the required pressures. 

A bare thermocouple is used to measure the temperature of a gas flowing through a hot pipe. The heat transfer coefficient bet ween the gas and the thermocouple is proportional to the 0.8 power of the gas velocity and the heat transfer by radiation from the walls to the thermocouple is proportional to the temperature difference. 

When a gas flows through a pipe the gas density is a function of the pressure and so is determined by the pressure drop. Equation 5.3 and Figure 5.7 can be used to estimate the pressure drop, but it may be necessary to divide the pipeline into short sections and sum the results. 

Figure 14.1 presents the main components of a typical in situ SVE system.910 Vertical extraction wells are installed inside the contaminated zone at appropriate distances from one another. The SVE wells are typically constructed of PVC pipe, with a screened interval, which is placed within the contaminated zone. The wells are connected to blowers or vacuum pumps, which induce a continuous airflow through the pores of the unsaturated zone. The soil surface is sometimes covered with an impermeable seal, made from high density polyethylene (HDPE) or bentonite clay for example, to prevent the vertical influx of air from the surface, which might cause short-circuiting problems, and promote horizontal gas flow through the contaminated area. The airstream, which contains the contaminant vapors, passes initially through an air-water separation unit to remove the entrained moisture and is then directed to the gas treatment unit, where the contaminants are thermally destroyed or removed by adsorption. 

The quantity of gas flowing through a piping element during a unit of time -in accordance with the two concepts for gas quantity desaibed above - can be indicated in either of two ways, these being ... 

Caution If the inlet side T1 for any cylinder end is hotter than the main gas inlet header pipe, then there is zero gas flow through this cylinder end. Then both the adiabatic and relative compression efficiencies are also zero. 

Circular Cross-section Pipes. In contrast to nozzles and apertures, the calculation of gas flow through tubes (/ d) has to take the effects of gas viscosity into account. For smooth-walled tubes, gas fluxes less than q l3 and laminar flow conditions, the well-known expression for p F-throughput, can be obtained ... 

Room A was also equippedfor the diffusion of carbon monoxide from the second steel container located in the exterior room. The installation consisted of a pipe (smaller in diameter than in room Bl), running along the southern wall [= eastern wall] and 30 cm above the floor. The gas flowed through perforated metal plates at both ends of the pipes, located in the corners of the room. No openings were made in the ceiling, and it was not possible to view the inside of the chamber from the side room. 

TEST A gas flows through a long pipe of constant diameter. The outlet of the pipe is higher than the... 

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