Design Of Industrial Applications Research Articles

Current Progress and Future Trends in Turbulent Combustion

ABSTRACT This article discusses some recent progress and future trends in turbulent combustion. Issues in turbulent combustion modeling (TCM) and some perspectives in active control are specifically considered. Modeling methods are first briefly surveyed to identify future developments. It is anticipated that further progress will be made in physical modeling based on flame surface density concepts and that physical modeling of turbulent flames will rely more heavily on modern computational tools like direct numerical simulation (DNS), large eddy simulations (LES), detailed numerical modeling (DNM) of simple flames. Physical modeling as it is practiced today will continue to evolve into more reliable methods for industrial design applications. As the computational resources progress one may also foresee that LES methods will take over and that research will shift from the Reynolds average approach to the more advanced LES computation of turbulent reactive flows. Because turbulent combustion is so complex, physical modeling and LES calculations will continuously need detailed experiments. These will emphasize field measurements based on imaging methods. It is expected that current progress in optical diagnostics will continue. Imaging diagnostics will become more easily applicable to practical situations. Their spatial and temporal resolution will be enhanced. Images will continue to provide qualitative information on the basic processes of turbulent combustion but improved experimental methods will yield more quantitative data. Another area which holds promises is that of active control. From current progress in this field one may foresee that advanced control schemes will play an increasing role in experimental investigations of instabilities and in practical optimization of turbulent combustors. “Intelligent combustor” concepts combining control loops with a combustion system are now being explored and will probably become of importance in enhancing the stability of combustion, in augmenting the domain of operation and in reducing the pollutant emission levels.

Chemical and physical variables in polymer-induced flocculation

The flocculation of fine-particle suspensions by polymers is a nonequilibrium process whose performance is strongly influenced by physical as well as chemical variables. A standardized test procedure has been developed that provides quantitatively reproducible measurements of process performance in terms of the floc settling rate supernatant turbidity and sediment compressibility. The procedure provides information on the development of flocs in response to polymer addition and on their degradation behavior during subsequent handling. Extensive experimental observations using a variety of solids and flocculant types have been used to develop criteria for reagent selection and process design. It is shown that the appropriate choice of reagent(s) is determined primarily by chemical factors (solid type, solution chemistry, etc.). However, actual performance depends more on physical variables such as agitation intensity and the rate of flocculant addition. Some general guidelines for flocculant selection and process design in industrial applications are suggested.

Controlling and Monitoring Induced Unconsciousness: Ergonomics and Design in Anesthesia

This research is the continuation of that presented in these proceedings in 1987; the application of Ergonomics and Industrial Design to the problems of the anesthesia workstation. However, the focus has grown from simple estimation of the unconscious patients depth-of-anesthesia (via brain stem, vagus nerve, esophagus) to the super-ordinate ergonomic problems of controlling and monitoring anesthesia; i.e., positioning and mobility of the clinician and equipment, information feedback, line of sight and reach, etc. This required the empirical determination of the necessary and sufficient patient-derived information required to manage each case, then making this information-gathering system the basis for the design of a new integrated monitoring system. The resulting system combines and displays all the necessary parameters in such a way that the clinician can determine the instantaneous or trended states of the patient, the system and the anesthesia procedure. Secondarily, the investigation has produced a novel attempt to classify the types of mental effort required during monitoring, also a head-mounted display to satisfy the clinicians need for mobility. The system is embodied in a single compact mobile monitor with interactive screens and lends itself to easy relocation and interrogation. Although not yet statistically proven, early feedback from researchers now using the prototype system suggests that it simplifies the clinicians task of maintaining the required heuristic “mental model” of the patient, system, and procedure.

Semiotics and marketing New directions in industrial design applications

A flexible discipline with a wide range of applications, the scope of the semiological analysis is here discussed first as a ‘global’ tool to assist in marketing communication decision, product choice decision, or in communication strategy planning, whether industrial, advertising or media. The aspect of intercultural marketing communications is also briefly examined. One application of this discipline discussed in detail is that of industrial design. Particular examples taken from the field of car design illustrate how the semiotician can use models derived from Gestalt psychology, linguistics and semantics to analyse car body shapes, chiefly in terms of legibility and expressivity. This research can be undertaken during product development, during test marketing or at any other phase of the product's existence.

Major parametric effects on isothermality in horizontal steam-generating tubes at low- and moderate-steam qualities

In some special boiler installations (for example, once-through boilers and fluidized-bed type boilers), horizontal or slightly inclined steam-generating tubes are used for technological or other reasons. One of the problems of these installations, leading to frequent failures, appears to be the circumferential anisothermality that occurs at certain operating and geometric conditions in the horizontal boiler tubes. This is a serious constraint for successful boiler design and maintenance. Although we have studied the subject both experimentally and theoretically in previous works, major parametric effects on the tube top-to-bottom isothermality resulting from distinct two-phase flow phenomena are identified in this paper. The anisothermality creates high temporal and spatial variations in thermal stresses, which is of utmost importance to engineers involved in the design of industrial applications containing horizontal tubes. Approximate relationships, design recommendations, and a practical example of the proposed approach are presented.

Toward Fast Color-Shaded Images of CAD/CAM Geometry

A software processor developed at RPI adds color-shaded imaging capability to 3-D geometric modeling systems, greatly enhancing their usefulness in industrial design applications.

An Energy Alternative for Industry—The High-Temperature Gas-Cooled Reactor Steamer

Large industrial complexes are faced with new requirements that will lead to a transition from such fluid fuels as natural gas and oil to such solid fuels as coal and uranium for supply of industrial energy. Power plants using these latter fuels will be of moderate size [800 to 1200 MW(thermal)] and will generally have the capability of co-generating electric power and process steam.A study has been made regarding use of the 840-MW(thermal) Fort St. Vrain high-temperature gas-cooled reactor (HTGR) design for industrial applications. The initial conceptual design (referred to as the HTGR Steamer) is substantially simplified relative to Fort St. Vrain in that outlet helium and steam temperatures are lower and the reheat section is deleted from the steam generators. The Steamer has four independent steam generating loops producing a total of 277 kg/s (2.2 × 106 Ib/h) of prime steam at 4.5 MPa/672 K (650 psia/750°F). The unit co-generates 46 MW(electric) and provides process steam at 8.31 MPa/762 K (1200 psia/912°F). The basic configuration and much of the equipment are retained from the Fort St. Vrain design. The system has inherent safety features important for industrial applications. These and other features indicate that the HTGR Steamer is an industrial energy option deserving additional evaluation. Subsequent work will focus on parallel design optimization and application studies.

Design equations for the complete shaking force balancing of 6R 6-bar and 6-bar slider-crank mechanisms

The article presents the design equations for complete shaking force balancing of commonly used planar Stephenson's and Watt's type 6R 6-bar and 6-bar slider-crank regular force transmission mechanisms using the method of linearly independent mass vectors. Regular force transmission mechanisms are those in which the shaking force can be completely balanced by distributing the masses of the existing links. Design equations are developed by considering the existing links. Design equations are developed by considering mass distributions of the coupler links and sliders specified whenever possible, so that the counter-balancing masses are mounted on the shafts supported by the fixed frame of the mechanism. Industrial design applications of the design equations given are illustrated in two numerical examples where the shaking force in a Stephenson's Type-1 6R mechanism and a 6-bar double-slider-crank mechanism used in V-engines is balanced.

Synthesis in the design of chemical processes

AbstractUntil recently, the subject of chemical process synthesis was largely ignored in the chemical engineering literature despite its importance in chemical engineering practice. However since 1968, attention to the subject has greatly increased and important progress has been made. This review article critically surveys the readily accessible literature in chemical process synthesis from two points of view: theory and applications. It is concluded that a number of effective synthesis tools are now available for application in industrial chemical process design. However, much more remains to be done, particularly with regard to the development of synthesis procedures which can lead to novel processing system structures.

Human Factors Interaction with Industrial Design

A working relationship between the fields of Human Factors and Industrial Design is postulated. It is described as a symbiotic relationship evolving out of the common objectives and unique methodologies of each discipline, and determined by the characteristics of the design problem that requires their collaboration. In working toward the solution of a specific problem, the disciplines exchange leadership roles as the contributions of each field selectively predominate during various stages of the development of a solution. Three examples are discussed in which human factors specialists and industrial designers collaborated to develop design solutions. In the first, a handheld weapon was designed in accordance with the findings of a human factors analysis. These findings established requirements for the industrial designer. In the second example, a system of console and workplace modules was designed by the simultaneous application of human factors and industrial design. In the third, the functional feasibility of a concept for a small field compass was established by the human factors specialist, and the structural feasibility was established by the industrial designer.