Dynamometer

Example 5. There are six dynamometers available for engine testing. The test duration is set at 200 h which is assumed to be equivalent to 20,000 km of customer use. Failed engines are removed from testing for analysis and replaced. The objective of the test is to analy2e the emission-control system. Failure is defined as the time at which certain emission levels are exceeded. 

Power consumption during metal cutting can be estimated from forces acting on a tool during the cutting. This can be measured on a dynamometer. In cutting operations the power consumption, P, at the spindle, in watts, is approximately equal to... 

Dynamometer and Vehicle Testing. Friction materials are evaluated in the laboratory by a great variety of tests and equipment. 

The full brake dynamometer, when properly instmmented and controlled, reflects the actual brake performance in a vehicle with reasonable accuracy. High initial investment is recovered through operation independent of the climatic conditions and by a fully automatic operation for extended periods, minimizing personnel costs. 

A. E. Anderson and co-workers, "Asbestos Emissions from Brake Dynamometer Tests," SAE PaperNo. 730549, SAE, New York, May 1973. 

The test for evaluating individual vehicle emissions, the ETP (4), specifies that a test vehicle be stored in an area where the ambient temperature is between 20 and 29°C for at least 12 hours immediately prior to the emission test. Then, the vehicle is placed on a chassis dynamometer which is calibrated for the vehicle weight and road load. The vehicle is started and driven for 41 min on a prescribed cycle of accelerations, cmises, decelerations, idles, a 10-min shutdown (called the hot soak), and a period of remn. 

The EPA regulation prohibits more than 2 grams per test to escape into the atmosphere (114). The test consists of a diurnal cycle of 1 hour where the temperature of the fuel is raised from 15.6 to 28.9°C during a 17 mile mn on a chassis dynamometer. An immediate hot soak in a shed enclosure follows the dynamometer mn. 

Dynamometer method (for medium-sized motors, say up to 500 h.p.). The output of an induction motor may be calculated by... 

Calibrated machine. When brake and pulley or dynamometer methods are not possible, the test motor may be loaded onto a calibrated generator. The efficiency curve of the generator must be available. 

Most ethylene plants operate continuously with the expanders operating at or near design conditions. If necessary, due to their unique design characteristics, radial inflow turboexpanders can accommodate a wide range of process conditions without significant losses in thermal or mechanical efficiency. Expanders may be loaded with booster compressors, gear-coupled generators, dynamometers, or other in-plant mechanical equipment such as pumps. In ethylene plants, turboexpanders are typically used in eitlier post-boost or pre-boost applications. 

When power levels are low or cannot otherwise be utilized, a dynamometer or an air brake (blower) may be used. Figure 3-11 shows a typical dynamometer-loaded turboexpander cross-section. 

The choice of a turboexpander load may be influenced by the desire to optimize refrigeration. In other words, a dynamometer load may be chosen over a generator load due to speed considerations. Additionally, there are other constraints imposed on optimal design. Factors such as impeller peripheral velocity (tip speed), bearing design, axial load balance, material selection, and manufacturing methods (which have greatly improved in the recent decades) all have an influence. 

One of the critical measurements is torque or shaft power. A variety of methods is recognized direct methods such as torque meters or reaction mounted drivers (dynamometers) and indirect methods such as electrical power input to drive motors, heat balance, or heat input to a loop cooler. See Part 7, Measurement of Shaft Power, PTC 19.7 1961 [3] for additional information. 

If a preference were to be given, it would be listed in the order stated above, recognizing that the dynamometer is limited in size, but works well with the PTC 9 class of equipment. 

Kraft-mehl, n. starch, amylum. -messer, m. dynamometer, -mittel, n. forceful means powerful remedy tonic, -packpapier, n. kraft (wrapping) paper, -papier, n. kraft paper, kraft. -papierstoff, m. kraft pulp, -quelle, /. source of power, -rad, n. motorcycle. -rdhre, /. (Physics) tube of force, -sammler, m. accumulator, -sitz, m. (Mach.) forced fit. -speicher, m. accumulator, -spi-ritus, m. motor spirit, -stoff, m. power fuel, motor fuel (Paper) kraft pulp, -stoffge-misch, n. fuel mixture, -stoffverbrauch, m. fuel consumption, -stoffwirtschaft, /. fuel economy, -strom, m. (Elec.) power current, -iibertragung, /. power transmission, -ver-brauch, m. power consumption, -verkehr, m. motor traffic. 

The schedule used to measure highway fuel economy (MPG, ), also driven on a chassis dynamometer, is diagramed in Figure 3b. It covers 10.2 miles in 765 seconds at an average speed of 48.2 mph and a peak speed of 59.9 mph. In contrast to the urban schedule, there... 

These laboratory tests may be followed by engine dynamometer tests (BS5117 Section 2.4 1985(1989)) and finally by road tests in working vehicles (BS 5117 Part 2 Section 2.5 1985 (1989)), thus completing the sequence of laboratory, field, service testing. 

D 2758 1986 Method of testing engine coolants by engine dynamometer... 

The present study was initiated to understand the causes of large differences in perfonnance of various catalyst formulations after accelerated thermal aging on an engine dynamometer. In particular, we wished to determine whether performance charaderistics were related to noble metal dispersion (i.e. noble metal surface area), as previous studies have suggested that the thermal durability of alumina-supported Pd catalysts is due to high-temperature spreading or re-dispersion of Pd particles [20-25]. 

Conversion efficiencies of the dynamometer-aged catalysts were measured in a standard A/F sweep test on an engine dynamometer [6]. The sweep experiments were carried out at 450 and 85,000 h space velocity (volumetric basis standard conditions). The sweep ranged from 0.5 A/F lean of stoichiometry to 0.5 A/F rich of stoichiometry with imposed A/F perturbations of+.0.5 A/F at 1 Hz. After sweep evaluation, small samples of catalyst were renrroved from the front region of the brick for chemisorption and flow reactor experiments. 

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