0


RESEARCH PAPERS

J. Eng. Power. 1963;85(3):165-174. doi:10.1115/1.3675240.

An analysis of internal combustion engine cycles using thermodynamic charts usually involves a lengthy trial-and-error process. A graphical analysis of the results of many cycles, however, enables equations to be developed for theoretical mean effective pressure and efficiency of the Otto cycle in terms of intake and exhaust pressures, fuel-air ratio, compression ratio, and fresh charge temperature. These equations enable quick solution of a particular cycle and the effects of operating parameters on engine performance to be studied. Experimental results show similar relationships between engine performance and operating parameters to those obtained theoretically.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):177-179. doi:10.1115/1.3675244.

Bending fatigue strength data from many tests on internal combustion engine crankshafts are analyzed. This analysis results in the development of simply related strength and geometrical parameters which summarize and unify the results. The data presented are for crankshafts of one material type but in a wide range of sizes and shapes.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):183-188. doi:10.1115/1.3675250.

Measurements of volatile and residue burning times of captive coal particles have shown them to vary in proportion to the square of the initial particle diameter; this was true for each of 10 coals tested. For the volatiles, the measured constant of proportionality was found to be independent of coal rank when allowance was made for swelling, the burning rate apparently being controlled by the diffusional rate of volatile escape through a porous matrix of fixed carbon. For the residues, the experimental “square-law” relation confirms Nusselt’s prediction; and agreement between predicted and experimental values of the proportionality constant was found to be good. An apparent rank dependence, showing shorter burning times with less fixed carbon, was simply a consequence of there being less fixed carbon to burn. There was no influence of rank-dependent “reactivity.” The relevance of the results to flames is also discussed.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):191-198. doi:10.1115/1.3675253.

An unconventional type of turbomachinery employing a rotor composed of smooth disks is described and the history and motive principle of such devices briefly recounted. An experimental program of research on such devices is described, together with a description of the design and testing of an experimental water pump, a blower, and an air compressor using multiple disk rotors. Data resulting from the testing of the devices are presented in summary form with discussions of the conclusions which the data allow. A “first-approximation” analysis is presented of the flow processes within the rotor and of the limiting performance and efficiency of multiple disk pumps. Solution of the resulting equations, found by digital computation, is presented for a wide range of geometry and of flow variables, in terms of dimensionless parameters. A brief discussion is given of possible applications of multiple dish pumps, compressors and blowers, and of the information now available for the design of the devices.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):201-206. doi:10.1115/1.3675258.

A radial-flow type shear-force pump is analytically and experimentally investigated and certain conclusions for the application of shear-force pumps in general are drawn.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):208-212. doi:10.1115/1.3675261.

The performance of p-n gridded, water-cooled silicon photovoltaic cells was measured at radiation levels of up to 250 Langley per min. Outputs exceeded 1/4 watt per sq cm. An analysis of cell operation at high fluxes permits computation of the performance over a wide range of radiation intensities from a single high-radiation voltage-current curve. An array of eight p-n cells and an optical system used with the array is described. Characteristics of n-p cells were measured, and their peculiar V-I curves are noted. Methods of improving cell performance at high fluxes are discussed.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):213-220. doi:10.1115/1.3675262.

The variation with wavelength of thermal radiation properties of coated surfaces is important for solar energy absorbers and in other applications, and depends on the optical properties of the coating material and the substrate, and on the structure of the coating. Theoretical considerations indicate that, for homogeneous coatings, the good optical properties of semiconductors can be improved if the coating contains a high fraction of voids. This improvement has been shown by experimental particulate PbS coatings which are not homogeneous; the selective properties of particulate coatings are better than those calculated for solid coatings at the same coating weight. PbS coatings on aluminum substrates show absorptances for solar radiation of 0.9 and long wave emittance of 0.2 to 0.3. The feasibility of selective paints has been demonstrated; PbS can be mixed with a transparent binder, silicone, to make a paint which shows a good degree of selectivity, and absorptances of 0.9 and emittances less than 0.4 have been obtained.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):221-228. doi:10.1115/1.3675263.

A set of general graphical relationships has been developed for establishing the receiver-reflector area ratio which will provide the maximum useful heat delivery from a focusing collector. The method, applied to paraboloids and parabolic cylinders, gives the optimum area ratio in terms of incident radiation intensity, optical properties (including precision of reflector), and thermal loss rate. Use of the method for design and for evaluation of existing reflectors is illustrated; its use in economic optimization will be dependent on availability of adequate cost data.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):229-234. doi:10.1115/1.3675264.

Sulfur in fuel oil and coal, and its resultant oxidation to SO3 during combustion, is a recognized factor in corrosion and deposits. As a step toward controlling the formation of SO3 , and eventually controlling the conditions and rate of corrosion, a program has been undertaken under ASME support to establish, among other things, the mechanism by which sulfur compounds are oxidized to SO2 and to SO3 in flames. The present paper reviews some of the basic thermodynamics and reaction kinetics pertaining to the oxidation of H2 S and SO2 , and to the SO2 –SO3 equilibrium. Included in the review are discussions of the stability of H2 S, the slow oxidation of sulfur vapor and of H2 S, the induction period (preignition) reactions leading to the fast, explosive oxidation of H2 S, and effects of additives on the explosion reaction. The heterogeneous (catalyzed) oxidation of SO2 is discussed in terms of the effects of specific catalysts on the SO2 –SO3 equilibrium.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):235-244. doi:10.1115/1.3675265.

A generalized thermometer well is analyzed as to temperature-measuring uncertainties. A reliable finite difference approximation to the differential heat balance equation is developed. For those cases where the fluid may be considered transparent to radiation (i.e., for εg ≈ 0), a simplified linearized approximation is given. Whenever conduction effects can be neglected (i.e., for (hc D/k)(L2 /(D2 − d2 )) > 20), a rapid hand-calculation method is indicated. Several examples of graphical approximations are given.

Commentary by Dr. Valentin Fuster
J. Eng. Power. 1963;85(3):245-248. doi:10.1115/1.3675266.

Usual means for sensing temperature in a gaseous flow carrying suspended liquid droplets invariably yield the liquid temperature only. In this paper, we discuss a probe configuration which separates the liquid from the gaseous phase for water/gas mass ratios up to 1.2, and which provides for sensing the temperature of the gaseous phase by means of a miniature thermocouple. The overall system exhibits response rates on the order of 10 milliseconds for the water/gas environment in which the probe was evaluated.

Commentary by Dr. Valentin Fuster

DISCUSSIONS

Commentary by Dr. Valentin Fuster

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In