Harvard Engineering Journal: A Quarterly Devoted to the Interests of Engineering in Harvard University, Volumes 3 à 41904 |
Autres éditions - Tout afficher
Harvard Engineering Journal: A Quarterly Devoted to the Interests ..., Volume 9 Affichage du livre entier - 1910 |
Harvard Engineering Journal: Devoted to the Interests of ..., Volumes 8 à 9 Affichage du livre entier - 1909 |
Harvard Engineering Journal: A Quarterly Devoted to the ..., Volumes 5 à 6 Affichage du livre entier - 1906 |
Expressions et termes fréquents
amperes angle arch architect Architecture armature attenuation constant belts boiler building cable Caliphs cent circuit coefficient coil column concrete conductors connected constant construction CORINTHIAN ORDER cornice corresponding curves cycle diagram diameter distribution Doric Doric Order effect electrical equations feet fictitious grade field flux frequency girders Greek HARVARD ENGINEERING JOURNAL HARVARD STADIUM heat Hitchin hysteresis impressed e. m. f. inches increase induction motor kilometre L. P. cylinder leakage reactance locomotive maximum miles Mosque ohms operation pair phase Plate platforms pole practice pressure primary Prof proportional railroad rails reactance reheater rods rolling friction running sand seat slabs secondary shown shows slip slots Soldiers Field speed square Stadium stations steam steel stone street surface telephone tests tion torque track tractive effort train resistance triglyph Tuscan Order vector voltage volts walls weight winding
Fréquemment cités
Page 49 - I neede now say no more concerning Columnes and their Adjuncts, about which Architects make such a noyse in their Bookes, as if the very tearmes of Architraves, and Frizes, and Cornices, and the like, were enough to graduate a Master of this Art...
Page 114 - bell" are placed two rows of leaves whose heads are curved. The first row, which is applied directly above the astragal of the shaft, is composed of eight leaves; these are called the small leaves. From the intervals between these small leaves arise the stems of the second row of leaves which are larger. Between these large leaves and just over the centers of the small ones, eight stems arise, from which develop eight other leaves which, divided into two parts, recurve above the large leaves at the...
Page 150 - B', C', each having twice the condenser capacity of the circuit in Kg. 44. frequencies, the capacity may be either lumped into a single condenser at the middle of the line, as in Figs. 45 to 47, thus forming the nominal T of the line ; or, as is usually more convenient for the purposes of computation, all the capacity may be collected into two equal condensers, and...
Page 103 - STADIUM steel structure. It was decided to have all supporting parts, such as walls, columns, floors, and arches, of concrete, while all inclined trusses, forming the immediate support of the seats, should be of steel. This seemed on the whole the best arrangement, as the steel underneath the seats would be fairly protected from the weather. After the engineering details had been worked out, the whole was submitted to Mr. CF McKim for criticism and modification, and drawings were made under his direction...
Page 102 - ... and then breaking them in the large testing machine. The results were instructive and valuable, and assisted materially towards deciding for concrete as the principal material for the Stadium. It is sometimes erroneously supposed that concrete is not reliable. While it does vary in strength, there is no reason why it should not answer for all purposes even better than limestone. The method of handling the ingredients and the care taken in mixing them has all to do with the results, if the cement...
Page 102 - Sankey's method applied to the Diesel motor, with the same broad river of heat, having a constant flow of 183,600 BTU per minute. The bulk of this enters the cylinder on its working stroke, but we have before lost more than thirty per cent, from three causes: The one is the actual negative work done in compressing the fresh air of the charge in the main cylinder, and which represents 30,700 BTU A very small stream is the heat expended in compressing air in the air pump, and a third stream, aggregating...
Page 237 - There being no separate steam supply to the reheater coils, nor any separate drain from the high pressure jackets, it is not possible to use either jackets or reheater alone. The receiver is a large cylindrical drum at the back of the engine and close to the cylinders. The reheater consists of one or more coils of pipe in the receiver. The low-pressure cylinder is unjacketed. I have gone into the principal details of this plant that you may appreciate the fact that the highest economy was sought...
Page 103 - ... the first diagram of the Louisville engine, this stream looks very large. In explanation, however, we must remember that the steam engine has four effective, or motor strokes, to one in the Diesel engine. As the latter has to do its whole work in this one stroke, while the frictions retard it, in all four strokes, it would be entitled to a percentage loss four times as great as that of the steam engine, without being subject to criticism as a mechanically inferior device. Furthermore, the total...
Page 105 - Many questions have been asked about the actual seating capacity of the Stadium, and much misinformation on the subject has been circulated by the newspapers. The structure is divided into 37 sections : each section has 31 rows of seats ; on the straight sides 20 or 21 persons can be placed in each row, on the curved end the number varies from 14 up to 26. The seating capacity, therefore, of that part on which stone seats are placed is either 21,000 or 23,000, dependent upon the way people are arranged....
Page 242 - ... All gauges, thermometers and indicators were calibrated. The water meter was calibrated during each run and the weight of water going to the main boiler was checked by feed pump displacement observations. The load on the engine was entirely electrical and consisted of the station load supplemented by an adjustable water rheostat load. - There was no difficulty in any of the tests in keeping the total load constant. The current for feed excitation was obtained from the main generator. All observations...