i
I
CHEMICAL ENOINEERINO REVIEWS
I OPERATIONS REVIEW
I
II Flow of Fluids I
THE
fields of engineering which utilize the science of fluid dynamics and which in turn contribute to the development of this unit operation are so many and varied that attempting to spotlight the more important paths of development is like choosing the most important strand of a spider web. I n the review there are discussed 10 different articles on flow of a single phase through various conduits-from the flow of liquefied gases to convective circulation. Of particular interest to those who study flow through large pieces of equipment is an analysis of errors involved in various methods of weighting nonuniform duct flows to determine average flow properties. A study of unsteady motion explains some inconsistencies between previous reports by demonstrating that responses to unsteady flow depend upon whether the resistance is due to surface, form, or jet action. The utility of the fluid mechanics approach in understanding energy processes in more complex equipment is demonstrated in a number of papers which discuss cyclones, furnaces, and other equipment. This year’s developments in surging flow problems include both theoretical and experimental investigations into pulsating systems of both liquids and gases and apply this information to some very practical problems. One of the less satisfactory situations in the field of pipeline design is the lack of knowledge of exact means of calculating flow of liquids that do not follow the simple viscosity patterns of Newtonian fluids. Current developments have yielded several correlations which may improve this situation. These have been tested over only a limited range of variables and await experimental confirmation over wider ranges. In addition, new methods are being developed for predicting viscosity characteristics for various classes of materials.
The most widely applied phase of fluid mechanics is that of metering fluid flows. The orifice plate and its modifications continue to receive more attention than any other single device; there are investigations into use in vacuum flow and flow a t very low and a t very high Reynolds numbers and discussions of modifications to meet special requirements, such as low head loss and wide range of constant coefficient. The Pitot tube finds application in the extreme cases of minute local flows and flows through extremely large conduits. Despite their wide applicability, the orifice and Pitot tube do not solve all . problems; nine other methods of measuring fluid flow are mentioned. A basic problem in flow metering receiving increasing attention is that of sensing and indicating the true values of pulsating flow. Several authors have discussed the techniques of averaging this type of flow, and one well-debated article has attempted to set thresholds below which the problem may safely be neglected. In the subdivision of this review according to the fluid phases involved, flow through porous and granular media is somewhat unique, inasmuch as the contours of the stationary part of the systems are as important as +e properties of the fluid. Work in this field increases at a steady pace with interesting developments in flow through beds of screen and of shot and through beds of low porosity and with the elucidation of the mechanism of displacement of one fluid from a porous media by a second fluid. Economically the solid-gas system of greatest importance is the fluidized bed, This is reflected in the description of several large industrial processes utilizing the principle of the fluidized bed as well as the publication of several novel schemes for handling other processes with this type of system. The over-all energy
MURRAY WEMTRAWB, a najive New Yorker, received his B.Ch.E. from the Cooper Union Institute of Technology and M.S. from the University of Pittsburgh. At the U. S. Bureau of Mines, Central Experiment Station, Pittsburgh, Pa. he is engaged in applied research on combustion of solid fuels and related studies of fluid mechanics. Weintraub is a registered professional engineer and a member of the AMERICAN CHEMICAL SOCIETYand AIChE.
requirements for operation of a fluidized bed are now well established, but problems of flow distribution, interphase contacting, and mass transfer within the beds are still being investigated. The dilute phase of solid suspension in gas is also receiving attention, evidenced by publication of articles on the behavior of individual particles and on practical applications in the cyclone furnace, cyclone dust collector, and pulverized fuel furnace. Solid-liquid systems are under investigation, both with respect to the motion of particles relative to the liquid, as is involved in problems of sedimentation and with respect to hydraulic transport. This latter subject is a source of considerable activity with published reports on energy requirements, experimental facilities, and heaters, piping, and other mechanical problems. Of outstanding interest is the construction of two systems for the hydraulic transportation of coal and of gilsonite over distances of 110 and 71 miles, respectively. Gas-liquid and liquid-liquid systems have received a moderate amount of attention with investigations on the flow of water and air mixtures, water and steam mixtures, free-falling droplets, and sprays of mercury in water. Mechanical problems covered in this review are subdivided into stationary devices, such as pipes and valves, and into rotating machinery. Pipeline design problems include those of dead-load and wind, temperature effect, steamtracing, layout and valving, and provision for corrosion. A novel solution to some problems of handling liquid metals lies in the design of freeze seals in which the flowing fluid is chilled so as to act as a combined seal and lubricant. Contributions dealing with rotating machinery are classified as relating to operating characteristics, mechanical design, or cavitation research. A number of the articles reviewed on mechanical and operating characteristics will be of value to the purchaser and user of compressors, pumps and turbines.
Single-phase Flow
Simple Channels. In surveying the field of floy through simple conduits a wide variety of subject matter is found. Wyatt (69A) shows that the use of conventional weighting methods may result in large errors in estimating the
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Dimensional standardization of centrifugal pumps would be advantageous but quite expensive.
average values of mass and momentum of a nonuniform spatial distribution of flow. He has developed an averaging method that yields correct values in the range of flow systems analyzed. Estimation of pressure drop for flow through standard pipe fittings has long been made by the use of the “equivalent length” concept. Decraene (73A) points out the limited applicability of published values and provides a new summary of available test data in a form into which new data may be injected. Buoyancy effects in hot gas systems may be studied in gas or liquid models. An improvement in this technique is being developed at the University of Sheffield (24A), where the high density fluid is represented by a magnetite slurry which has the advantages of a wide range of relative densities and is easily photographed. Daily (724 has investigated accelerated and decelerated floiv of water through smooth tubes and orifices. In flow through a uniform tube it was found that the boundary resistance at any instant during accelerated motion was slightly greater than the equivalent steady-state case, while for decelerated motion it was slightly less. The reverse was true in the case of flow through orifices. The authors conclude that when resistance is caused by boundary shear stresses, transients cause moderate change in resistance; when caused by conduit forms which generate high shear and turbulence-for example, jets from small orifices-transients produce large effects. Another investigation in unsteady-state operation is reported by Alstad (34,on unsteady-state operation of natural circulation loops with various temperature gradients. Flow through Equipment. Thoughtful analysis of all the energy conversions possible in a given system frequently reveals methods of improving system efficiency. Zinkl (77A) analyzes a cyclic energy process and calculates the influence of flow losses on the total efficiency of the process. The effect of pressure upon furnace combustion is tabulated by Reynst (47A), who estimates that the thermal efficiency of a boiler can be increased by 4.570 if the furnace is operated under conditions of pulsating combustion. Thring (59A) describes an approach to improving furnace performance by model investigations. Yano ( 7 0 4 discusses the pressure drop in cyclones and reports observations on the effect of inserting a Pitot tube into a small cyclone on the distribution of velocity and static pressure. Donohue
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(76,4) presents nomograms which summarize methods of computing pressure drop through shell and tube heat exchangers. Several different aspects of the flow branching and manifold problem are treated by Acrivos, Babcock, and Pigford ( 7 A ) , by \%‘inter (67A), and by Allen and Albinson (2‘4). Surge Flow. When fluid velocities vary with time, the destructive effects of water hammer and of gas pulsations may be generated. A major parameter in the determination of surge wave magnitude and velocity is the elastic properties of the containing pipe. Kennison (29A) contributes important information about wave velocities in concrete pipes. Another interesting paper (7A) explains the water hammer calculations which were made for certain power plant penstocks and shows the good agreement of test results with the calculations. Pressure surges in gas systems do not usually have the same damage potential as in liquid systems, but their control is made considerably more difficult by the compressibility of the fluid. Ken,man and Moerke (47A) describe the use of reactive and resistive elements in
INDUSTRIAL AND ENGINEERING CHEMISTRY
Table I.
the control of pulsation induced by reciprocating compressors. Design and efficiency problems created by pulsations in the inlet systems of internal conib[istion engines are discussed in two papers by Tsai and coworkers (58.4, 6OA). Non-Newtonian Fluids. \t’hen the physical properties of a fluid prevent it from following the simple Newtonian laws of constant viscosity, estimation of flow and pressure drop may br difficult. Three different correlarions (704, 37‘4. 64.4) are offered, each of which is experimentally substantiated over a given range of fluids. -4 broad experimental program is needed before a completely general method of attack will become acceptable. Methods of predicting nonA-ewtonian viscosity ar? contributed by De \Vitt (7\FL4) and b y Ree and Eyring (454, 46.4). Jet Mixing and Boundary Layers. I n the gas jet compressor a stream of high-prpssure gas is used to boost a second stream of lower-pressure gas to an intermediate pressure. Dotterweich and Mooney (77A) give typical operating characteristics of this device. They demonstrate the interdependence of
Instruments and Instrumentation
A. General Principles Dynamic analysis of control loop components Mass-rate metering methods; review Feeding, metering, and proportioning liquids ; review Methods of measuring Mach numbers Mathematical compensation ; commercial instruments for pulsating flow Magnitude of the mean-value error due to pulsation Threshold for neglecting the error of pulsation Response of pressure probe to pulsating flow Fast response meter with electronic linearization Elimination of pulsation errors in manometers H. Orifice Meters and Modifiuatiotis Nomograms for vacuum flows New coefficients for low Reynolds numbers Flow through sonic orifices Effect of approach piping Dall flow tube Theory of rounded entrance flowmeters Special orifices and nozzles for low Reynolds number flow C. Pitot Tubes Electric indicator Three-dimensional Pitot probe Pitot-tube bar for water in large pipes Properties of a cantilevered Pitot cylinder D. Miscellaneous Methods for Metering Flow Review of spark, corona, and other gas discharge methods Radioactive gas for multistream metering Radiotracers in determining duct profiles Flow of rivers by salting Mass metering with high accuracy turbine Large capacity with angular momentum principle Propellor meters in penstocks High velocities metered with sound wave photography Change in velocity of propagation of ultrasound Sonic anemometer for wind vectors Ultrasonic measurement of large quantities of water flow Flow by measurement of heat transfer through boundary layer Stable hot-wire anemometer Visual flow patterns with smoke and dye tracing
motive gas pressure, motive gas rate, suction pressure, and suction rate. Pressure distribution and weight-flow rate can be predicted for laminar fluid flow in a thin passage by use of methods presented by Grinnell (ZZA). A simplified method is used when the passage is so small that the viscous action predominates over that due to acceleration of the fluid, and a more complicated trial and error method is developed for larger passages. Fluid resistance in thin passages is undoubtedly one of the main forces present in the action of a regenerative pump. Several theories of the fluid-dynamic mechanism of this machine are compared by Senoo ( 5 4 4 , who believes that some of these theories are compatible, differing chiefly in the assumptions made, and that each theory is applicable over a limited operating condition and geometry. A hypothesis which treats a regenerative pump merely as a modification of a centrifugal device is supported by Wilson, Santalo, and Oelrich ( 6 6 A ) with data from observations of commercial pumps. Boundary layer theory is used by Deissler (144) to study turbulent heat transfer and friction in the entrance regions of smooth passages. Results, supported by some experimental data, indicate that approximately fully developed heat transfer and friction are attained in an entrance length less than 10 diameters. Ross (504 shows that the ratio of pressure drop and head loss to the corresponding values for fully developed pipe flow are practically independent of Reynolds number. Mixing and diffusion of mass and of momentum in boundary layers and in jets have been the subject of a number of investigations. Pai ( 4 3 4 , Weinstein ( 6 2 A ) , and Laurence ( 3 2 A ) have studied jet mixing on a theoretical and experimental plane, and Sandborn and Slogar ( 5 2 A ) have measured turbulent spectra of boundary layers. Cooper and Tulin ( 7 7 A ) have surveyed the hot-wire anemometry techniques essential in many of these investigations. Batchelor ( 6 4 , reviewing the difficulties associated with analysis of diffusion in turbulent motion, points out the chief source of difficulties: many different mechanisms contribute to the diffusion, such as longitudinal diffusion due to nonuniform velocity, convective transfer of eddies, and molecular transport. Instrumentation. Corresponding to the manifold aspects of fluid flow theory and practice are the many aspects of instrumentation development.
Flow through Porous Media A major obstacle to an adequate analysis of flow through porous beds is the difficulty of securing geometrically similar beds over a wide range of porosity or of varying pore diameter while retaining constant particle diameter.
Two attacks on this problem have been made. Coppage and London (2%) simulated a porous bed by the use of wire screening and lead shot. The porosity and surface for the beds of screen were described by the corresponding values for a single screen and the introduction of the additional parameter of screen spacing. Observations of pressure drop and heat transfer were represented in the usual manner, with modified definitions of friction factor and Reynolds number to include the extra parameters of bed geometry. Brownell (7B)decreased the porosity of beds of uniformly sized spheres by consolidating them and partially filling the intentices with a resin. The data were analyzed in terms of an effective pore volume, and equations were developed for predicting pressure drop by use of a friction factor-Reynolds number plot similar to that previously developed for beds of spheres. An apparatus for determining relative permeability of two liquids under the high pressure conditions obtaining in oil reservoirs has been developed. WiIson (5B) reports that relative permeability measurements at 5000 pounds per square inch are essentially the same as those measured a t 30 pounds per square inch. Deemter (3B) has studied the quantity of fluid retained under conditions of displacement and report that for Poiseuille flow the holdup is a function of the molecular diffusion coefficient, the mean residence time, and the capillary tube radius. According to Von Rosenberg (&) the shape of the displacement profile and the length of the zone of mixing are dependent upon the rate of flow, the diffusion coefficient, the characteristics of the pore geometry, and the distance the displacement front has traveled.
Multiphase Flow
Solid-Gas Systems. The fields of applicability of solid-gas systems are fairly well defined in terms of the concentration of solids, although for research purposes the extreme cases of dilute suspension and of moving packed beds are frequently used as tools in the analysis of the more complex fluidized bed. Fluidization constitutes the most active group in this field, probably because of the dramatic expansion in its application and the challenge offered to the investigator by the complexities of the process. A recently published book (26C)consists of a symposium of nine papers, the first two of which are comprehensive surveys of the present state of knowledge of fluid dynamics and heat and mass transfer design correlations; the remaining seven papers describe modern industrial practice in design, operation, and control of various types of processes and mechanical units.
Basic gas requirements for the initiation of fluidization reported previously have generally been valid for only a limited range of conditions. For predicting this quantity Leva (79C) has developed a new equation which does not require a knowledge of the minimum voidage of the bed or the shape factor of the particle. The primary parameter for all fluidization calculations is particle diameter. Investigating the fluidizing properties of coal and of char, Jacobs and Minet ( 1 6 C ) have emphasized the calculation of the correct mean diameter for mixtures. Their choice of the representative diameter is the reciprocal mean. Another practical problem is that of maintaining stable flow distribution through a bed. Corrigan and Mills (SC, QC) have shown how stable flow may be produced by balancing the falling pressure dropflow characteristic of a fluidized tube against the rising characteristic of a properly chosen orifice. The intimate relationship between flow distribution and catalyst activity in a fluidized bed has been used by Johnstone, Shen, and Batchelor (77C, 37C) to evaluate gas-solid contact. They measured the rate of ammonia oxidation and of nitrous oxide decomposition in both fixed and fluidized beds and partitioned the observed reaction rates into portions taking place in a continuous phase comparable to the fixed bed and portions dependent upon mass transfer from the discontinuous phase. They concluded that the latter rate is a function of gas velocity and independent of particle size and that the velocity effect is very much dependent upon bed depth. Among novel fluidizing schemes and new processes, Godel ( 7 4 2 ) has described a furnace firing 40,000 pounds per hour of coal which is fluidized on a moving grate that removes slag and clinkers which have built up to settling size. The walls of the fluidizing chamber consist of unburned coal; fluidized air is pulsed to provide a large range of particle size suspension. Two other units have been described (3‘2, 28C), wherein solids are moved horizontally from one fluidizing chamber to the next, maintaining considerable fluidizing volume with low headroom. A somewhat more conventional method of achieving shorter units is the use of dense phase catalyst transfer which is one feature of a large “catalytic cracker’’ described in considerable detail by McWhirter and associates (27C). Descriptions of a Fischer-Tropsch pilot plant (75C) and of a British patent disclosure for heat treating combustible solids ( 7 7C) provide additional useful ideas for fluidization units. As a contribution to the study of flow of solids without benefit of fluidization, Franklin and Johanson (7ZC) have
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UNIT OPERATIONS REVIEW measured the flow of grains through horizontal circular orifices and have correlated their data in the form of an empirical equation. Within certain geometrical limits the mass flow rate is affected mainly by orifice diameter, particle diameter, particle density, and angle of repose of the granular material. Flow patterns around an isolated smooth sphere represent the extreme condition of infinitely dilute suspension. A calculation by Basina and Tonkonogii (PC)provides an estimate of the time for the separation of particles in a cyclone furnace over a wide range of sizes. The comparison of separation time with combustion time agrees with other evidence that most of the particles burn in the layer of slag on the combustion chamber wall. Barth (7C) has related cyclone dimensions and fluid properties with flow data to obtain an estimate of factors of merit for the design of cyclones for gas-solids separation. A problem of considerable interest to a number of experimental investigators is the behavior of solid particles tracking combustion gases. Gilbert and associates (73C) integrated the equation of motion in order to calculate the behavior of particles in the reaction zone of a laminar flame and in the propellant combustion of a rocket motor. For the sake of better comparisons, papers on pneumatic conveying are discussed in the next section lvith papers on hydraulic transport. Solid-Liquid Systems. Investigations in this field can be classified according to whether they deal with the motion of the entire suspension relative to the conduit, the particle relative to the liquid, or the particle relative to the conduit. A paper on the rheology of suspensions of cement (27C) is typical of the first class, in which the major interests lie in the viscometry of the suspension and its classification as a Bingham fluid or a pseudoplastic liquid. The work of Marris (23C), ivho studied the distribution of suspended sediment over depth of a very wide river, is typical of the second class. His calculations of the concentration distribution of sediment showed that the mean concentration occurred at 0.65 of the stream depth. Dell and Whelan (70C) found that they could improve the separation of coal from shale by the use of horizontal agitation sufficient to reduce internal friction in thick suspensions without interferring with vertical motion. Under these conditions, specific gravity and not size determines the direction of motion of given particles. An exception to this conclusion was that highly angular particles responded like lighter ones; the authors suggested that these particles hold envelopes of fluid which reduces their average specific gravity.
500
The third classification in this field is represented by developments in hydraulic transportation. Two notable advances in the field of hydraulic transport are the completion by the Pittsburgh Consolidation Coal Co. of a 110mile coal pipeline, to satisfy a contract calling for the delivery of 18,000,000 tons of coal over the next 15 years (30C) and the announcement (5C) of plans for the production of gasoline from gilsonite. For the latter, a gilsonite-water slurry will be elevated 100 to 1500 feet from the working face to the surface, and then pumped through 71 miles of 6-inch pipe from mine to plant. Steadman (34C) makes a general survey of the operations involved in hydraulic transport and of possible applications. Growing interest in commercial application of hydraulic transportation is shown in the description of two experimental facilities for establishing flow properties of slurries in pipelines and in pumps (‘IC, 7C). A comprehensibe report and discussion of hydraulic transport of solid materials are given by Worster and Denny (36C). They present a simple empirical correlation of available data and discuss design of feeders and pipeline and problems of degradation of the solids in transit. Energy requirements for hydraulic transport have been studied by a number of investigators. Spells (33C) obtained rough correlations from literature data for the minimum velocity required to prevent deposit of the solids and for that velocity, which he labels “standard velocity,” below which friction is greater than for the equivalent Newtonian liquid of the same density as the slurry and the same viscosity as the water. Smith‘s investigations (32C) provide additional data for sand concentrations of up to 27% by volume in pipes of 2-inch and 3-inch bore. Theoretical equations are derived by Newitt and coworkers (25C) for the head loss along a pipe in terms of the mean velocity of flow, the concentration, size, and density of the solids, and the pipe diameter for the various types of flow met in hydraulic conveying. These are compared \vith experimental results obtained in a 1-inch pipe. In contrast to the long distances considered for hydraulic transport, pneumatic conveying is used over comparatively short distances. Because of this and of the much greater slip between solids and gas, much of the energy injected for pneumatic conveying is absorbed in accelerating the solids. Weidner (35C) gives adequate consideration to this fact in his theoretical analysis, based essentially upon single particle flow characteristics. Because of the simplifying assumptions made, Weid-
INDUSTRIALAND ENGINEERINGCHEMISTRY
ner’s results await comparison with a large body of experimental data. Gas-Liquid Systems. One of the distinctive features of gas-liquid systems is the variety of possible modes of flowlayer, waving, or slugging. Levi (2OC) attempted to treat the emulsion type of system as a single-phase fluid but found that the coefficient of friction is not constant. A new formula was suggested that relates air concentration to hydraulic characteristics of the conduit. A new empirical correlation for turbulent two-phase flow, developed by Chenoweth and Martin (K),was derived from observations on air-water flow in larger pipes and at higher pressures than the experiments of Lockhart and Martinelli. It agreeswith that of the previous investigators in the lower ranges but deviates markedly at extreme conditions. Because of the complex energy rclationships involved, the flow of evaporating fluids presents both theoretical and practical difficulties. Monroe (2-/C) has presented a useful empirical relationship for the flow of saturated watcr through several orifices in series. He found that the flashing of the liquid into vapor is a much more important factor than any variations in the orifice discharge coefficient and that stable flow conditions between expansions seem to exist at distances over 6 inches. Maker (232) has shown that computation of pressure drops in heaters with evaporating fluids may frequently be simplified because of a linear relationship between the pressure-volume product and the enthalpy. He showed how allowances are to be made for velocity heads, especially in return bends where the changes are important. In one aspect of the mechanics offalling drops, van der Leeden and others (78C) have investigated the drag function applicable to the free fall of liquid droplets. They found that in the region of Reynolds numbers 500 to 1600 this function \vas independent of the Reynolds number and a unique function of kVeber’s number; the drag coefficient could be calculated by assuming an approximately elliptical deformation of the falling drops. Pierce (?!IC), studying another aspect of d r o p w k flow, reports that when droplets of mercury were spra!.ed into rising steams of water, each drop dragged downward with it a small surrounding mass of ivater countercurrent to the main flow. This film provided the principal resistance to heat transfer.
Mechanical Design In this section there are reviewed articles dealing with mechanical problems such as steam tracing and piping layout which may be met by an operat-
FLOW OF FLUIDS ing chemical engineer and with such aspects of equipment performance as will assist the chemical engineer in intelligent choice and specification of equipment. Table I1 includes additional references to these subjects as well as to other items which, while of general interest to the engineer using the equipment, usually fall into the province of the mechanical engineer. Piping and Accessories. Proper layout of steam ‘tracing systems, including lines, traps, and condensate return, was described by Long (770). The proceedings of an “Experience in Industry” symposium (6D) present the various problems of piping systems planning, choice of valves and pumps, and operation and maintenance which are met in the application of fluid flow to the practice of petroleum refining. Bauer (30) has discussed the techniques necessary to ensure absolute tightness in reactive and toxic systems such as those utilizing liquid metals. His major advice is one of meticulous attention to detail. For example, separate welds should be used for structural and sealing purposes. Seal welds should not be made with coated welding rod, since slag might initially make a tight seal which would eventually be dissolved by the liquid metal. Holmberg (730) describes other design considerations to be given for corrosive fluids. He points out the necessity for considering the type of corrosion to be met when designing equipment-for example, where crevice corrosion is prevalent special attention must be paid to designing valve parts, piping connections, and other components so as to minimize threads or other crevices. The freeze seal (90) is also offered as an answer to corrosion problems of moving parts. Rotating Machinery. A nine-paper L
Table II.
Mechanical Design ReferSubject Matter ence A. Pipelines and Accessories External loads and deflections of overhead pipelines ($70) Cold springing to minimize high temperature creep (8.W New tabular method for calculating pipe stresses (140) Control valve performance (160) Valve design for scraped pipelines (1D ) B. Rotating Machinery Design of centrifugal and axial flow compressors (book) ($60 Design of axial flow liquid pumps (40) High-suction centrifugal pumps ($90) Losses in centrifugal impellers (1W Performance of Francis pump-turbines (18D) Optimum stages of axial flow turWgD) bines Developments in large centrifugal pumps (.W
symposium (80) provides a detailed review of compressors, fans, and other gas movers and their accessories in terms of application, selection, and design factors for each type. Another paper of value in pump selection is by Rostafmski (240),who describes the operating characteristics of centrifugal compressors and points out the much greater sensitivity of operation and narrower operating limits than the comparable liquid pump. When a pump is required to perform under conditions differing from those on which its original specification was based, other problems may arise. If it appears inadequate because of repeated mechanical failures, the user is frequently a t a loss to decide whether remedy lies in a simple change in operating load or a bearing repair or whether a unit must be discarded. U1lock, Reynolds, and Hudson (280) show how this question can be answered by appropriate measurements of shaft deflection. A new pump now being offered for handling of abrasive slurries (70) achieves its purpose by the use of a large volume, long cycle expanding sleeve which is extended by hydraulic pressure. The dimensional standardization of centrifugal pumps would have considerable advantages for the chemical industry. However, this could be accomplished only a t substantial costs for new designs and tooling. Brand (50) and Murdock (790) debate the advantages and costs of standardization from +e viewpoints of user and of manufacturer. Cavitation. Possibly the least understood phenomenon of importance in hydraulic design and operation is cavitation. Robertson (270) discusses the general principles of this phenomenon and its probable scaling factors and describes the research tools currently available. Existing knowledge of the occurrence of cavitation in pumps has been entirely experimental. Stahl and Stepanoff (250) attempt to extend these data to other operating conditions by inclusion of thermodynamic properties of the liquids that are involved. Daily and Johnson (700) have applied thermodynamics to analyze the effects of turbulence and boundary layer upon cavitation inception from gas nuclei. Ellii and Plesset (770, 200) have produced accelerated cavitation damage by an acoustic field and have shown that chemical activity is not required, inasmuch as equal damage could be produced in an inert atmosphere. Their conclusions are that plastic deformation occurs, leading to cold work and fatigue failure. Knapp (76D), however, estimates that bubble collapse should not be rapid enough to cause damage, and through the medium of high speed motion pictures he has shown that a
so-called fixed cavity is actually a cyclic formation and breakoff with a multitude of small cavities sweeping along the surface. After comparing the frequency of bubble collapse with a rate of pit formation, he has concluded that pits are formed by single blows and not by fatigue of the solid material.
Literature Cited Single-Phase Flow Acrivos, A., Babcock, B., Pigford, R. L., A.1.Ch.E. meeting, Detroit, Mich., November 1955. Allen, J., Albinson, B., Proc. Instn. Civil Engrs. (London) 4 (No. 1, Part 3), 114 (1955). Alstad, C. D., Isbin, H. S., Amundson, N. R., Silvers, J. P., A.Z.Ch.E. Journal 1, 417 (1955). (4.4) Aniansson, G., Aniansson, G., Noren, O., Tek. Tidskr. 86 (No. 21,
VOL. 49,
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Barry, F. W., Trans. Am. SOC.Mech. Engrs. 78, 581 (1956). Batchelor, G. K., Appl. Mechanics Rev. 9 (No. 3) 89 (1956). Brathch, A. E., Cartwright, K. O., Tram. Am. SOC.Mech. EngTs. 78, 1329 (1956).
Catheron, A. R., Hainsworth, B. D., IND. END.CHEM.4 8 , 1 0 4 2 (1956). C h m . Eng. News 34, 3300 (1956). Christiansen, E. B., Ryan, N. W., Stevens, W. E., A.I.Ch.E. Journal i, 544 (1955). Cooper, R. D., Tulin, M. P., AGARDograph No. 1 2 (1955). Daily, J. W., Hankey, W. L., Jr., Olive, R. W., Jordaan, J. M., Jr., Trans. Am. SOC.Mech. Engrs. 78, 1071 (1956).
Decraene, E. P., Valve World 54 (No. I), 24 (1956). Deissler, R. G., Trans. Am. SOC. Mcch. Engrs. 77, 1221 (1955). De Witt, T. W., J. Appl. Phys. 26, 889 11955).
Donohhe, D: A., Petroleum RcJsner 34 (No. l l ) , 175 (1955). Dotterweich, F. H., Mooney, C. V., Zbid. (No. lo), 104 (1955). Dupin, P., Compt. rend. 240, 1687 (195 5 ).
Elkott. D. E.. Aero. Chart. 6 (Part 3),
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181 ( 1 9 5 5 j.
Fucks, W., A$@. Sci. Research E 5 (NO. 1-4), 167 (1955). Greenhalgh, R. E., Miller, J. W., (No. l ) , 222 (1956). d i E i i ~ TK.,~ Trans. Am. Sac. Mech. Engrs. 78, 765 (1956). Head, V. P., Ibid., 78, 1471 (1956). Horn, G., Univ. Shefield Fuel SOC.J. 7, 19 (1956): Industrial Development Laboratories, Inc., Jersey City, N. J., “Laub Electro-Caloric Flowmeter,” Bull., 1956. Iversen, H. W., Trans. Am. SOC. Mech. Engrs. 78, 359 (1956). Jorissen, A. L., Zbid., 78, 365 (1956). Jung, R., Bremtof- Warme-Kraft 7 (No. 7 ) , 300 (1955). Kennison. H. F.. Trans. A m . Sod. M c c h . Engrs. 78; 1323 (1956). Kritz, J., Instruments and Automation ~
28, 1912 (1955).
Kronauer, R. E., Grant, H. P., “Proceedings of Second U. S. National Congress on Applied Mechanics, June 1954,” p. 763, American Society of Mechanical Engineers, New York, 1955. NO. 3, PART II
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501
UNIT OPERATIONS REVIEW Laurence, J. C., Natl. Advisory Comm. Aeronaut., Tech. Note 3561 (1955). (33.4) Lee, J. C., Ash, J. E., Trans. A m . Soc. ’llech. Engrs. 78, 603 (1956). (34.4) Li, Y. T., Am. SOC.Mech. Engrs., Paper 55-SA-79 (1955). (35A) Li, Y. T., Lee, S. Y., Ibid., 55-SA-72 (1955). (36.A) Lowy, L., Chem. E n g . 6 3 (No. 5 ) , 175 (1956). (37.4) Metzner, A. B., Reed, J. C., A.I.Ch.E. Journal 1, 434 (1955). (38.4) Miner, I. O., Trans. A m . Soc. M e c h . Enprs. 78. 475 (1956). (39.4) Mull&, H.7 P., kasse;uirtschaft 45 (No. 8), 193 (1955). (40.4) hfurdock, J. W’., Foltz, C. J., Gregory, C., Jr., Trans. A m . Soc. hfech. Engrs. 78, 369 (1956). Newman. C.. Moerke. N. H., Am. SOC.Mech: Engrs., Paper 55-Pet8 11955’1. (42.4) Numachi, F., Murai, H., Abe, S., Trans. A m . Soc. .2lech. Engrs. 78,
1079 (1956). (43‘4) Pai, S.I., J . Appl. kiech. 22 (No. 1), 41 (1955). Product E n g . 26 ( S o . 8), (44.4) Perry; C. d, 154 11955’1. (45A) Ree, T., Eyiing, H., J . Appl. Phys. 26, 793 (1955). (46.4) Ibid., p. 800. (47‘4) Reynst, F. H., Energie 7, 361 ( t 9 5 5 ) . (48A) Richardson, F. hl.. Ferrell. J. K.. Lamonde’, H. A,; Beatty,’K. 0.: Jr., iYucleonics 1 3 ( S o . 7 ), 21 ( 1955). (49‘4) Rivas, hl. A., Jr., Shapiro, A . H., Trans. A m . Soc. ;tlech. Engrs. 78,
(50A) (51.4)
(52.4)
(53.4)
489 (1956). Ross: D., Ibid., 78, 915 (1956). Rousselet, R., Chaleur t 3 ind. 36, 217 (1955). Sandborn, V. A . , Slogar, R. J.; Xatl. Advisory Comm. Aeronaut., Tech. Note 3453 (1955). Schotland, R. hf., J . .\feteor. 12 (No. 4), 386 (1955).
(54A) Senoo, Y., Trans. A m . Soc. J l e c h . Engrs. 78, 1091 (1956). (55.4) Shepard, C. E., Xatl. Advisory Comm. Aeronaut., Tech. Note 3406 (1955). (56.4) Swengel, R. C., Hess: W. B., Waldorf, S. K.. Trans. A m . Sac. .Mech. Engrs. 77, 1037 (1955). (57.A) Taylor, C. F., Am. SOC. Mech. Engrs., Paper 56-AV-20 (1956). (58‘4) Taylor, C. F., Livengood, J. C., Tsai, D. H.?Trans. A m . Sac. Atlech. Engrs. 77, 1133 (19551. Thring, Sf. W., Coke and Gas 17 (.4pril), 133, (May), 176 (1955). Tsai, D. H., Trans. A m . Soc. .lIech. Engrs. 78, 197 (1956). Vagas, I., Hidrol. Korlony 35 (No. 5/6), 202 (1955). Weinstein, A. S., Osterle, J. F., Forstall, W., J . Appl. .\fech. 23 (No. 6), 437 (1956). Weir, A . , Jr., York, J. L., Morrison, (63‘4) R. B., Trans. A m . Sac. .Mech. Engrs. 78, 481 (1956). Weltmann, R. N., IND.ENG.CHmi. 48, 386 (1956). Williams, T. J., Trans. A m . Sot. Mech. Engrs. 78, 1461 (1956). Wilson, W. H., Santalo, M. A., Oelrich, J. A , , Ibid., 77, 1303 (1955). Winter, ’H,, Osterr. Ing.-Arch. 9 (No. 2/3), 239 (1955). Winternitz. F. A. L.. Engineer 199. 729 (1955). Wyatt. De M. D.. Natl. Advisorv Comm. Aeronaut., Tech. Note 3400 (1955). I
502
.
,
(70A) Yano, T., Kitaura, Y., Yamaguchi, T., Takako, T., Chem. E n g . ( J a p a n ) 19, 388 (1955). (71A) Zinkl, R.,Brensto~-Tl/hrme-Kraft 7, (No. 81, 350 (1955).
Flow through Porous Media (1B) Brownell, L. E., Gami, D. C., Miller, R. A,, Nekarvis, W. F.! A.I.Ch.E. Journal 2, 79 (1956). (2B) Coouaee. J. E.. London. A. L.. Chem. ,- - , (3B) Deemter, J. J. van, Broeder, J. J., Lauwerier. H. A . , Appl. Sci. Research A-5 (No. 5), 374 (1955). (4B) V o n Rosenberg. D. E., A.I.Ch.E. Journal 2, 55 (1956). (5B) Wilson, J. W., Ibid., 2, No. 1, 94
(1956).
Multiphase Flow Barth, W.,Brenstoff- ll’irme-Kraft 8 (No. l ) , l(1956). Basina. I. P.. TonkonoKii. A. V.. TeploenergetLh-a 1955, 17. Chem. Eng. 63 (No. 2), 116 (1956). Ibid. (No. 5), 242. Chem. Eng. ‘Yews 34, 3546 (1956). Chenoweth: J. Si.,hlartin, M. LV., Petrolrum Rpfiner 34 (No. lo), 151 (1955). Coiliery Engineering 32, 425 (1955). Corrigan. T. E., hfills, LV. C., Chem. E n g . 63 (No. 5 ) , 203 (1956). Ibid., (No. 6)>253. Dell, C. C., Whelan, P. F., J . Inst. Fuel 28, 462 (1955). (11C) Dorr Co., Jukkola, W. W., Brit. Patent 728,868 (Appl. April 23, 19531. ___.,
(12C) Franklin, F. C., Johanson. L. K., Chem. E n g . Sci. 4, 119 (1955). 113‘2) Gilbert, M., Davis, L., Altman. D., J e t Propulsion 25, 26 (1955). (14C) Godel, A . , Porcer 100 (h-0. 7 ) , 86 (1956). (15C) Hill, C.‘ C., Taylor, A . H., J . Inst. Petroleum 41, 101 (1955). (16C) Jacobs, J. K., Minet, R. G., A.1.Ch.E. Meeting, - . New Orleans, La., May 1956. (17C) Johnstone. H. F.. Batchelor. J. D.. Shen, C. Y., A’.I.Ch.E. Journal 1 ; 318 (1955). Leeden, P. van der, Liem, D. N., Suratman, P. C., Appl. Sci. R r search A-5 (No. 5 ) , 338 (1955). Leva. M.. Shirai. T., Wen, C.-Y.. (2OC) Levin, L., H o u k e Blanche 10, 555 (1955). (21C) McWhirter. W. E., Jr., Tusson, J. R., Parker, H. A., Petroleum Refiner 35 (No. 4), 201 (1956). (22C) Maker, F. L., Zbid., 3 4 (No. 11,, 140
(1955). (23C) Marris, A. W., Can. J . Technol. 33, 470 (1955). (24C) Monrok, E. ’S., Jr., Trans. Am. Soc. Mech. Engrs. 78, 373 (1956). (2.5’2) Newitt, D. M., Richardson, J. F., Abbott, M., Turtle, R. B., Trans. Inst. Chem. Eners. 3 3 (No. 2). 93 (1955). (26C) Othmer, D. F., ed., “Fluidization,” Reinhold, New York, 1956. (27C) Papadakis, M., Reu. ma‘teriaux construction et trav. publ. 476, 121 (1955). (28C) Parsons, C. A., and Co., Ltd., Osola, V. J., Brit. Patent 738,026 (Appl. Jan. 7 , 1953).
INDUSTRIAL AND ENGINEERING CHEMISTRY
I
(29C) Pierce, R. D., Dwyer, 0 . E., Martin, J. J., A.1.Ch.E. Meeting, Detroit, Mich., November 1955. (30C) Pittsburgh Post-Garettep. 24(Sept. 13, 1956). (31C) Shen, C. Y., Johnstone, H. F., A.I.CI2.E. Journal 1. 349 (19553. Smith, R. A , T r a i s . Ins;. Chem. Engts. 33 (No. 2), 85 (1955). Spells, K. E.: Ibid., 33, No. 2. 79 (1955). Steadman, A. T., Chem. 3 Process E n g . 36, 168 (1955). Wridner. G.. Forsch. Gebiete Ingenieurw’. 21 (No. 5), 145 (1955). (36C) Worster, R. C., Denny, D. F., Inst. ‘Mech. Engrs. Proc. 169 (No. 32), 563 (1955).
Mechanical Design (1D) Anderson, A. G., Valve W70rid 54 (No. 2), 34 (1956). (2D) Anderson, H . H., Inst. Mech. Engrs. Proc. 169 (No. 6), 22 (1955). (3D) Bauer, S. G., Chem. Enq. Progr. 52 (No. 2), 75-F (1956). (4D) Bokverman, R. D., Am. SOC..Mech. Enqrs., Paper 55-A-127 ( 1 955). (5D) Brand, D. C . , Chem. Eng. Progr. 52 (No. 4), 130 (1956). 16D) Csddell, J . R . , ed., “Fluid Flow in Practice,” Keinhold, New York, 1956 (7D) Chem. Eng. 63 (No. 3 ) , 238 (1956). (8D) Ibzd., (No. 6), p. 175. (9D) Cygan, K., Stelle, A . hl., ChPm. Enq. Proer. 52 (No. 4). 157 11956). (10D) Daily; J. bi’.; Johnson. ‘V.E., Jr., Am. SOC. Llech. Eng., Paprr 55-A-142 (1955).
(11D) Ellis, A. T., J . Acoust. Sur. Amer. 27, 913 (19.55). (12D) Hamrick, J. T., 7’runs. Ani. Soc. Afech. Engrs. 78, 591 (1956). (13D) Holmberg, E. G., Corrosion 11, No. 9. 58 119551. (14D) Hsiao, K. H:, Prtroleum Rrjirier 3 4 (No. lo), 157 (1955). (15D) Johnson, C . h i . , Fallis, J. hl.. .\in. SOC.Mech. Engrs., Pdper 55-A152 (1955). (16D) . I R I l a D D . R. T.. ’I’rons. Am. SOL. -MkLh:E n u s . 77. 1045 (1955 I. (17D) Long, J. F.: Pdro1;urn Rgfinu 35 (No. 7), 187 (1956). (181)) McCormack, Wr. J., 7’ranj. A m . &or. Mech. Engrs. 78, 417 (1956). (19D) hfurdock, hf. I,,, Lhenr. Eng. Progt. 52 (No. 4). 135 (1956). (20D) Plessit. hf. S.. Ellis. A . T.. Trans. \
I
Am. SOG.Mech. Eiigrs. 77, 105.5 (1955). (21D) Robertson, J. M.,Ibzd., 78, 95
(1956).
(22D) Robinson. E. L., Ibid., 77, 1147
(1955). (23D) Ross, C. C., Banerian, G., Am. Soc. Mech. Eng., Paper 55-A-124 ( 1 955 1. (24D) Rdsrafin‘ski, W. A , , Petroleum Rpfiner 3 4 (No. lo), 116 (1955). (25D) Stahl, H. A., Stepanoff, A. J.: Am. SOC. Mech; Eng., Paper 55-A-136 (1955). (26D) Stepanoff, A. J., “Theory, Design and Application of Centrifugal and Axial Flow ComDressors and Fans,” Wiley, New $ark, 1955. (27D) Sweeney, R. J., Chem. Eng. 63 (No. 3), 199 (1956). (28D) Ullock, D. S., Reynolds, J. A , , Hudson, T. W., Chem. Eng. Progr. 5 2 (NO.l ) , 3-5 (1956). (29D) . . V a n Le. N., J . Aeronaut. Sei. 22. 503 (1955).
