Fluid stream

The principle of operation of the hydraulic reciprocating pump is similar to the beam pump, with a piston-like sub-surface pump action. The energy to drive the pump, however, is delivered through a hydraulic medium, the power fluid, commonly oil or water. The power fluid drives a downhole hydraulic motor which in turn drives the pump. A separate surface pump delivers the hydraulic power. The power fluid system can be of the closed loop or of the open type. In the latter case, the power fluids are mixed with the produced fluid stream. The performance of the hydraulic pump is primarily monitored by measuring the discharge pressures of both surface and sub-surface pumps. 

The statistics of the detected photon bursts from a dilute sample of cliromophores can be used to count, and to some degree characterize, individual molecules passing tlirough the illumination and detection volume. This can be achieved either by flowing the sample rapidly through a narrow fluid stream that intersects the focused excitation beam or by allowing individual cliromophores to diffuse into and out of the beam. If the sample is sufficiently dilute that... 

Basic Heat-Transfer Equations. Consider a simple, single-pass, parallel-flow heat exchanger in which both hot (heating) and cold (heated) fluids are flowing in the same direction. The temperature profiles of the fluid streams in such a heat exchanger are shown in Figure 2a. 

Optimum heat-transfer results when the thermal capacity rates of the two fluid streams are balanced, ie, where or = 1.0. 

The term pressure drop usually refers to the pressure loss that is not recoverable in the circuit, and it is lost energy that is dissipated into the fluid stream in the form of heat energy. The pressure drop in a flow circuit is associated with various forms of energy dissipation owing to friction, change in flow area, flow turning, and others ... 

Direct Contact Heat Exchangers. In a direct contact exchanger, two fluid streams come into direct contact, exchange heat and maybe also mass, and then separate. Very high heat-transfer rates, practically no fouling, lower capital costs, and lower approach temperatures are the principal advantages. 

A second property, closely related to the first, is the abiHty of the heat pipe to effect heat-flux transformation. As long as the total heat flow is ia equiHbrium, the fluid streams connecting the evaporatiag and condensing regions essentially are unaffected by the local power densities ia these two... 

All elements of a given fluid stream have the same thermal his-toiy in passing through the exchanger. ... 

Corrosion fouling. The heat transfer surface reacts chemically with elements of the fluid stream producing a less conductive, corrosion layer on all or part of the surface. 

Biofouling. Organisms present in the fluid stream are attracted to the warm heat-transfer surface where they attach, grow, and reproduce. The two subgroups are microbiofoulants such as shme and algae and macrobiofoulants such as snails and barnacles. 

In all of these configurations, maintaining longitudinal flow on both the shellside and tubeside allows the decision for placement of a fluid stream on either one side or the other to be based upon design efficiency (mass flow rates, fluid properties, pressure drops, and veloci-... 

Regenerators are by nature intermittent or cycling devices, although, as set forth previously, the Ljunstrom design avoids interruption of the fluid stream by cychng the heat-retrieval reservoir between the hot and cold fluid streams. Truly continuous counterparts of regenerators exist, however, and they are called recuperators. 

Basic to establishing whether power recovery is even feasible, let alone economical, are considerations of the flowing-fluid capacity available, the differential pressure available for the power recovery, and corrosive or erosive properties of the fluid stream. A further important consideration in feasibihty and economics is the probable physical location, with respect to each other, of fluid source, power-production point, and final fluid destination. In general, the tendency has been to locate the power-recoveiy driver and its driven unit where dictated by the driven-unit requirement and pipe the power-recoveiy fluid to and away from the driver. While early installations were in noncorrosive, nonerosive services such as rich-hydrocarbon absorption oil, the trend has been to put units into mildly severe seiwices such as amine plants, hot-carbonate units, and hydrocracker letdown. 

If chemical reactions occur only over the catalyst and none on the walls or in the homogeneous fluid stream in the recycle loop, then conservation laws require that the two balances should be equal. 

Total temperature is the temperature rise in the gas if its veloeity is brought to rest in a reversible adiabatie manner. Total temperature ean be measured by the insertion of a thermocouple, RTD or thermometer in the fluid stream. The relationship between the total temperature and static temperature can be given ... 

A. Hougen and K. M. Marshall Adsorption from a Fluid Stream Flowing Through a Stationary Granular Bed, Chemical Engineering Progress, 43 197 (1967). 

When a hot fluid stream and a cold fluid stream, separated by a conducting wall, exchange heat, the heat that is transferred across a differential element can be represented by the following expression (refer to Figure 1) ... 

In this manner, an average value of U can be applied to the whole exchanger. Ideally, the heat lost by the hot fluid stream is transferred totally to the cold stream, and hence, integrating results in the following expression ... 

Jet a fluid stream having a velocity greater than the surrounding fluid which discharges from a nozzle or impeller. 

From an industrial viewpoint, the objective of the unit operation of filtration is the separation of suspended solid particles from a process fluid stream which is accomplished by passing the suspension through a porous medium that is referred to as a filter medium. In forcing the fluid through the voids of the filter medium, fluid alone flows, but the solid particles are retained on the surface and in the... 

In a fluidized bed reaetor, the solid material in the form of fine partieles is eontained in a vertieal eylindrieal vessel. The fluid stream... 

As a simple and efficient particle separation device, cyclone collectors can be used for anything from dust removal in a fluid stream to material collection in the fluid conveying system. However, the cyclone is not suitable or economical for the separation of extremely small particles (say, less than 1 /xm), which frequently occur in industrial processes. It is recommended that the size of particles to be separated in an industrial ventilation cyclone be in the region of around 10 to 100 p.m. However, for the purpose of aerosol sampling, the size of particles to be separated may be much less than 10 jxm. 

Blender An enclosure in which two different fluid streams are mixed. 

Cooling load, sensible The quantity of hear to be removed from a fluid stream to maintain a desired fluid temperature. 

Degasser A packed tower through which a fluid to be degassed flows. Air is forced through the fluid stream, stripping the gas from the liquid. 

Filter Any medium used for the separation of solid, gaseous, or liquid contaminants from a gas or fluid stream. The collection efficiency depends on the materials used. Some types of filters are listed here. 

Filtration The process of removing particulate or gaseous matter from a fluid stream. 

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