China
Africa
Explore chapters and articles related to this topic
Materials
Published in Ansel C. Ugural, Youngjin Chung, Errol A. Ugural, Mechanical Engineering Design, 2020
Ansel C. Ugural, Youngjin Chung, Errol A. Ugural
Toughness is usually associated with the capacity of a material to withstand an impact or shock load. Two common tests, the Charpy and Izod tests, discussed in the next section, determine the impact strength of materials at various temperatures. We observe that toughness obtained from these tests is as dependent on the geometry of the specimen as on the load rate. The units of both the modulus of toughness and modulus of resilience are expressed in joules (N ⋅ m) per cubic meter (J/m3) in SI and in in. ⋅ lb per cubic inch in the US customary system. These are the same units of stress, so we can also use pascals or psi as the units for Ur, and Ut. As an example, consider a structural steel having Sy = 250 MPa, Su = 400 MPa, εf = 0.3, and E = 200 GPa (Table B.1). For this material, by Equations (2.18) and (2.20), we have Ur = 156.25 kPa and Ut = 97.5 MPa, respectively.
Water Hydraulics
Published in Frank R. Spellman, The Science of Water, 2020
The relationship shown above is also important: Both cubic feet and pounds are used to describe a volume of water. There is a defined relationship between these two methods of measurement. The specific weight of water is defined relative to a cubic foot. One cubic foot of water weighs 62.4 lb. This relationship is true only at a temperature of 4°C and at a pressure of one atmosphere [known as standard temperature and pressure (STP)—14.7 lb/in2 at sea level containing 7.48 gal]. The weight varies so little that, for practical purposes, this weight is used from a temperature 0°C to 100°C. One cubic inch of water weighs 0.0362 lb. Water 1 ft deep will exert a pressure of 0.43 psi on the bottom area (12 in × 0.0362 lb/in3). A column of water 2 ft high exerts 0.86 psi, one 10 ft high exerts 4.3 psi, and one 55 ft high exerts55 ft×0.43 psi/ft=23.65 psi
Coal
Published in Roy L. Nersesian, Energy Economics, 2016
Suppose that Mary and Joseph deposited one penny at the first Christmas at a local savings and loan bank that gave 3 percent interest on the outstanding balance. No withdrawals were ever made. At 3 percent compound growth, what is the current value of the deposit? Taking the current value of gold per troy ounce, what would be the value of the deposit in terms of troy ounces? There are 10.17886 troy ounces in a cubic inch. A cubic foot is 12" × 12" × 12" or 1,728 cubic inches or 17,589 troy ounces. How many cubic feet of gold does the balance represent? What is the radius in feet of a solid sphere of gold that could be purchased today given that volume is equal to 4/3 Pi R3? Redo for 5 percent growth: the compounding factor makes a big difference!
In-situ measurements of engine particulate filter ash deposits via X-ray computed tomography scanning
Published in Aerosol Science and Technology, 2021
Yujun Wang, Ben Wang, Carl J. Kamp, Leigh Rogoski, Connor Ryan, Michael J. Cunningham
Two quarter-size DPF parts, named DPF #11 and #12, are used in the validations. After the necessary CT scans, multiple 1 cubic inch samples, which are suitable for the mechanical density measurements, are extracted from the quarter-size parts. As shown in Figure 5a, four columns (A, B, C, and D), with a cross section of 1 inch × 1 inch and at different radial locations, are removed from the quarter-size parts with caution. Then, three segments (i.e., A1, A2, and A3) of 1 inch length are taken from each column at the designed axial locations, as illustrated in Figure 5b. From CT images, it is quite straightforward to calculate the average ash density in each cubic inch sample. In parallel, the average ash density in each cubic inch sample can be measured by the mechanical method. Although the ash volume in the small samples can be obtained by other methods (i.e., microscope imaging at the two ends of the sample), the total volume of ash in the sample is integrated by 3 D CT images, which helps to reduce the sample handling times and the resulting particle loss.
The square root rule – a case study of a scaling factor for machines with dynamic similitude
Published in Mechanics Based Design of Structures and Machines, 2020
Robert E. Farrell, Jiradech Kongthon
As it turns out, the injection units also follow the same scaling factor as for the clamping system. The clamp size is selected by the molder according to a rule of thumb of 2 US tons/inch2. Thus the expected projected area of the part is proportional to the clamp force. During the molding filling, the melt experiences a pressure drop due to shear losses in the runners and parts. Thus, larger parts require a greater wall thickness. On the basis that the average part thickness is larger for larger parts, then it would be reasonable to scale the thickness using the square root rule. Thus, the required shot size for a 1000 US ton machine should be four times the area and twice as thick or eight times the volume. This is (1000/250)1.5 or eight times that of the 250 US ton machine. The screw diameter for the 250 US ton machine was 2.5 inch (63.5 mm) and its maximum stroke was three diameters or 7.5 inch (190.5 mm) for a rated shot size of 36.8 cubic inch (603 cm3). According to the square root rule, the screw diameter for the 1000 US ton machine should be 5 inch (127 mm) with a maximum stroke of 15 inch (381 mm). The shot size would be 294.5 cubic inch (4826 cm3). This is eight times the shot size of the 250 US ton machine.
Humphry Davy’s Early Chemical Knowledge, Theory and Experiments: An Edition of His 1798 Manuscript, “An Essay on Heat and the Combinations of Light” from The Royal Institution of Cornwall, Courtney Library, MS DVY/2
Published in Ambix, 2019
Expt: 21st. One cubic inch of Conferva fæniculacea previously dried was put into a Phial containing 13 cubic inches of Hydrogen Gas. It remained in a heat of 58° for six hours & at the end of that time was examined. The Hydrogen Gas was diminished 8/10s of a cubic inch, I could get no ballance sufficiently accurate to determine