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Surface radiation damage to laser optics is a problem unique to laser-fusion reactor design. Of the radiation sources created by fusion reactions, the optics appear to be most vulnerable to neutron radiation damage. Although no specific designs are available, some general evaluations of anticipated problems will be presented.

The University of Wisconsin fusion research program is divided between plasma physics and fusion reactor technology studies. Both research and teaching are the integrated efforts of several departments, with a substantial number of courses available to both graduate and undergraduate students. The program has been successful in producing students for the national controlled thermonuclear research program. It has also produced significant research results, particularly in the toroidal confinement and conceptual reactor design fields. (auth)

The advent of enzyme immobilization, allowing re-use of enzymes, and essentially eliminating product contamination, has greatly increased the potential of enzymatic processes for industrial use. Although this is a relatively new field of study, the literature is rapidly expanding. The compendium of references prepared by the New England Research Applications Center for Corning Glass Works now lists over 800 papers concerning immobilized enzymes. For this reason the scope of this paper is limited to immobilized enzyme engineering, including reactor design and performance. Although medical and analytical applications of immobilized enzymes are important, they will not be discussed as such here. Another large body of information concerning enzyme immobilization techniques will be treated only briefly as an introduction. Other general articles and reviews [1–5] may be useful in providing additional background information.

Chemical engineers comprise a significant segment within the U. S. nuclear industry, yet few study nuclear subjects before they begin their careers. Nuclear chemical engineering is defined, then, as an arena for action rather than a field of knowledge. Of the classical problem areas in nuclear chemical engineering, fuel fabrication and isotope separation have made the best recent progress. Radiation chemical engineering, once an activity of ebullient promise, is nearly moribund. Only rarely do chemical engineers approach the central locus of reactor design; when they do the results are often ambivalent or worse. Surprisingly, perhaps, chemical engineering has made several important contributions to elementary particle physics. Fusion technology presents many challenges for creative chemical engineering, e.g., in fuel recovery, gaseous permeation, and the materials effects that result from ionic bombardment. (auth)

The physical factors that may affect the performance of a microbial reactor for producing syntlietic protein are reviewed in ternis of chemical engineering principles. In particular, it is shown that an appreciation of these principles can be used to maximize the productivity of synthetic protein from liquid-hydrocarbon and cellulose fermentations.

The problem of homogeneous and heterogeneous reactions in tubular flow reactors has been studied on the basis of the axial dispersion model. The model parameters are evaluated ‘a priori’ and the quantitative results of the reactor exit concentration obtained on the basis of this model are compared with the exact numerical solution. It is shown that the model gives good predictive results for reactor design purposes.

The results of two-dimensional (r,z) multigroup calculations of an experimental low-power reactor (PPA-19) are described. Comparison is made between calculated results and experimental measurements of reactivity, power distribution, and sodium activation. Generally good agreement is observed between calculation and experiment. This calculation was performed in 1954 and represents the first application of Roe's two-dimensional multigroup formulation to the analysis of an operating critical assembly. The over-all objective of such calculations is to ascertain the accuracy of two-dimensional multigroup methods in order to facilitate their application to future problems in reactor design. (auth)

The various ways of operation of a two-phase system with consecutive reactions are discussed. The conversion rate and the yield-conversion relation are evaluated for batchwise, co-current and countercurrent continuous operation. The effect of mixing of either of the two phases is considered for both co-current and counter-current flow, with the tank reactor and the respective plug-flow type reactor as the extremes.

A new continuous method for preparing aniline from nitrobenzene by Bechamp's reduction method has been developed, using a liquid fluidized bed of iron particles induced by upward flowing liquid reaction-mixtures. Outline of the experimental apparatus is shown in Fig. 1.The rate data obtained from this small-scale continuous apparatus in Fig. 3, when compared with those by batch reduction, showed that the latter is somewhat lower than the former. Possible reasons are presented for this lowering.It has turned out from this basic survey that aniline of 99 to 99.9% purity may be prepared in industrial scale without much difficulty, using this new continuous method. Quantitative formulation of the behavior of the reactor has been developed, including reactor design of multistage type in series

The notions of instantaneous and overall reaction yields are developed more fully than in earlier papers. Experimental methods of determining instantaneous yields are described and also the method of using the results for calculating optimum reactor design. This is illustrated by reference to two examples, one concerned with a reaction of known kinetics and the other with a reaction whose mechanism is unknown.

The application of electrical simulation methods to nuclear reactor calculations considerably shortens the time required for the computational work. In this review the advantages and disadvantages of simulators are discussed and an example is given of the simulation of the reactor isotopic composition with the help of the simulator MN-7. The effectiveness of the electrical simulation method for the investigation of non-stationary reactor processes is shown by an example of design calculations carried out for an automatic power regulator for a reactor. It is shown that it is possible to simulate nonstationary processes occurring in a power reactor, taking into account the temperature coefficients of the reactivity; other applications of simulators in reactor design are indicated.

New pressurized water reactor designs are obtaining higher efficiencies and smaller physical size by operating primary coolant loops at higher temperatures and pressures. Since the ultimate temperatures and pressures are limited by the critical point of water and instrument errors, highly accurate process-type instrumentation is required and the instrument engineer becomes an important member of the reactor design team.

Plutonium, the man‐made element of atomic number 94, has established itself mainly as the fissile component of nuclear weapons. It is always made in the operation of a uranium‐fueled reactor and has been manufactured in large quantities since its introduction in World War II. It has long been considered inevitable that plutonium will become an important reactor fuel. It offers hazards and puzzles to reactor physicists, and for two reasons in particular they must know the conditions under which assemblies containing it become critical. First, they must design processing systems that will not have accidental and dangerous chain reactions. Second, they need data for reactor design.

The following paper is in the form of a review of the scope of high speed computer methods as applied to a particular reactor design study in connexion with which the author has been responsible for the mathematical work. For a more general review the reader is referred to, e.g., H owlett (1958). By reviewing a particular design study the author has been able to discuss certain aspects of the work in some degree of detail, but even so it has not been possible in the space available to do more than review the types of problems to which machine methods have been applied in the pursuance of this specific study: the derivation of equations (most of which are, however, now well-known) and the evaluation of results has had to be omitted. It is hoped to publish more detailed papers dealing with more specialized branches of the subject in subsequent issues of Reactor Technology.

This paper reviews research in the area of polymerization systems engineering. Polymerization systems engineering is divided into six subareas: thermodynamics, modeling and simulation, optimal reactor design, dynamic optimization, stability analysis, and optimal synthesis. Basic concepts of polymerization are presented, and research in these subareas is reviewed. It is concluded that much remains to be done.

A brief description is given of the measurements and calculations of the ZR-5 project which worked out the nuclear design of the Polytechnical University’s Training Reactor. The system of programs — the reactor physical model — used in the calculations is described together with some of the experimental techniques, that have confirmed high precision and great potential value. It is emphasized that most nuclear aspects of reactor design and operation can be effectively studied with such a calculation model.

The consideration about the concentration stability in the isothermal reactor is made in this paper. The heterogeneous catalytic and the autocatalytic reactions are employed for this purpose. The technical problems of the reactor design and operation are also considered from this point of view.

Comparative dimensional data from irradiation experiments that included both high temperature isotropic (HTI) and low temperature isotropie (LTI) carbons show that at high fluences the volume expansion and accelerations in the dimensional change rates are considerably more pronounced for HTI carbons than for LTI carbons. Alloying LTI carbons with up to 15 wt-% silicon enhances the dimensional stability slightly at ~ 600°C but has no effect on the behavior in irradiations at higher temperatures. For HTI carbons the effects of the alloying additions are more pronounced. In neither case, however, are the improvements thought to be of practical importance. Data from both multiple irradiations at different temperatures and irradiations in which the temperatures were programmed down during the course of the irradiation show that prior irradiation at high temperature markedly enhances the dimensional changes that occur in subsequent irradiations at lower temperature. The implications of these findings to reactor design are discussed.

The prediction of chemical yield and productivity for packed tubular reactors is examined in two articles. A mathematical model and digital computing scheme are presented for reactors with several reactions, large heat effects, and heat exchange at the wall. Case studies show that yield loss depends strongly on the dimensions and flow rate adopted in reactor design. Part 1 presents a steady state reactor model based on material and energy balances formulated in partial differential equations on radial and axial space coordinates. The model allows for multiple reactions with arbitrary rate expressions and stoichiometry, axial bulk flow, radial effective diffusion and conduction, and a heat transfer resistance at the wall. Problems of scale-up and similitude are discussed in terms of the model. Part 2 presents the numerical computing scheme and case studies.* Le probleme de la prevision du rendement des reacteurs tubulaires a garnissage est etudie dans une serie de deux articles. Dans la premiere partie, un systeme d'equations aux differentielles partielles en coordonnees radiales et axiales est etabli pour un reacteur continu, non-adiabatique, operant en etat de regime et dans lequel plusieurs reactions accompagnees d'effets thermiques appreciables peuvent avoir lieu simultanement. Les problemes de prototypes et de modeles reduits sont discutes a la lumiere de ces equations. La seconde partie expose une methode de calcul a l'aide de calculatrices numeriques et les resultats d'etudes particulieres.

An accurate prediction of the hydraulic losses in multirod fuel bundles is necessary for reactor design calculations. Correlations of the pressure drop at the spacers are important for these calcul...

The equations which describe the performance of a continuous tubular photochemical reator have been formulated and analyzed by dimensional analysis. Experimental data obtained in a study of the decomposition of hexachloroplatinic acid in water were correlated as suggested by the dimensional analysis, thus partially confirming the validity of the approach.

This paper discusses the use of EHV shunt reactors on transmission systems from the application and reactor design viewpoints. Various factors relating to reactor construction, including testing, are discussed, and emphasis is placed on a gapped-core design for EHV applications. The results of steady-state and transient performance studies for this design are presented.

The mathematical problems of reactor design and performance depend primarily on the solution of a set of partial differential or difference equations. These equations are linear if the reactions are first-order, if temperature variations are not significant, and if mass transfer by diffusion obeys Fick's law. When a reactor problem can be solved for a single irreversible first-order reaction, it can also be solved for a system of coupled first-order reactions of any number of chemical species and of arbitrary complexity. Les difficultes mathematiques du calcul des reacteurs et de leur performance proviennent du Systeme d'equations differentielles a resoudre. Ces equations sont lineaires lorsque les reactions sont du premier ordre, les variations de temperature sont negligeables et le transport de masse par diffusion suit la loi de Fick. Lorsqu'un probleme de reacteur peut ětre solutionne dans le cas d'une seule reaction irreversible du premier ordre, il peut aussi l'ětre pour un Systeme complexe de reactions de premier ordre.

This paper traces the development of heat exchangers for gas-cooled reactors, indicating the influence that the reactor design has had on the Magnox system and, more recently, on the reactors of the advanced gas-cooled type. It also discusses the possible line of development of boilers for the proposed High-Temperature Reactor which is the logical development of the present A.G.R. system. This survey highlights particular problems such as the choice of tube surface and the preferred method of fabricating individual units, i.e. whether boilers should be contained in separate pods within the reactor vessel or in a single compartment around the core. Other items discussed are the choice of tube material for the developing gas conditions, the problem of control in once-through systems, and the problem of operation with varying load conditions which will arise when the installed nuclear capacity exceeds the base load. Reference is also made to the degree to which boiler units of the above type can be fabricated in other countries.

L. S. Pontryagin's maximum principle is used for solving problems in which it is necessary to find the minimum critical size of a reactor for a given power or to find the maximum power for a given critical size . Recently Pontryagin's maximum principle [1] has been successfully used both for determining the optimum transient conditions for reactors [2, 4] and for finding the optimum spatial arrangement for reactors with prescribed physical characteristics [1]. In the present study this principle is used in two otherproblems encountered in the theory of reactor design.

The spectral-synthesis method is investigated to assess its applicability for solving the diffusion equation in fast reactor design. The equations are derived so they may be solved by a standard di...

Criteria defining the stability of forced water circulation through heated passages are introduced. A general method is derived for predicting stability criteria for a system with any form of variation of heat input with respect to passage length. A convenient method for calculating pressure loss is developed. Criteria and integrated functions are presented for the forms of heat-input distribution commonly encountered in reactor design, and their application is demonstrated in a worked example.

The theory and design of continuous stirred tank reactors are extended to the complex but industrially important field of continuous-heterogeneous-reaction systems. The present investigation is concerned with the elementary process occurring when solid particles and a liquid flow into and from a single reactor or a chain of these reactors. The equations are developed for dissolution processes, and the theoretical size distributions and specific areas are confirmed experimentally. Performance is also related to operating conditions and reactor design.

A method has been developed for evaluating flux and reactivity changes in a reactor due to long-term changes in the quality of the fuel under irradiation. An account is given of the method, and the results in two simple cases. It is tentatively concluded that the permissible maximum heat output and channel ratings may vary very considerably during the lifetime of a charge, a point of possible importance in reactor design.

The determination of ratios of spectrum-averaged cross sections from isotopic concentrations is described along with their application to verification of analytical reactor design tools. The determ...

The decision to use beryllia in a reactor requires a balance between cost and performance in the light of a continually developing technology and reducing costs of raw materials. This paper attempts to summarise some of the properties of beryllia most pertinent to high temperature gas-cooled reactor design and to discuss the relative advantages in improving these properties; the fabrication processes are discussed whereby improved properties are most likely to be attained at minimum cost.

1. 1. A study was made of catalytic hetero-cyclization of a butane-butylene fraction and hydrogen sulphide in various laboratory reactors. It was found that this reaction is effectively carried out in a fluidized catalyst layer: thiophen yield increases markedly compared with the yield obtained using a stationary catalyst layer. 2. 2. A laboratory vibratory reactor design is proposed with effective fluidization of the catalyst layer. 3. 3. By simplex experimental planning optimum process conditions were found by which thiophen yield in a fluidized layer reaches 90%.

Recaps fission physics and reactor design, then relates the evolution of nuclear fuels to that of reactors

In many chemical operations for which large scale reactors must be designed, the rate of reaction is influenced by the fact that chemical and physical processes may proceed with comparable rates. This leads to considerable difficulty in constructing appropriate models for studying the behavior of reactors. In this paper, a few representative techniques which have been found useful are described, and compared with methods for modeling combustion chambers.