Ambient testing

In well-controlled ambient tests, the Expected MAC is often close to 1. A complementary measure of the mode shape uncertainty is the expected value of the hyper angle between the random mode shape vector and the most probable mode shape vector. It can be shown that under the same asymptotic conditions in Eq. 37, the expected value of the hyper angle is given by... 

Tests on mineral oils are split between ambient tests concentrating on the action of additives, and temperature controlled tests. 

The Ohio State University (OSU) calorimeter (12) differs from the Cone calorimeter ia that it is a tme adiabatic instmment which measures heat released dufing burning of polymers by measurement of the temperature of the exhaust gases. This test has been adopted by the Federal Aeronautics Administration (FAA) to test total and peak heat release of materials used ia the iateriors of commercial aircraft. The other principal heat release test ia use is the Factory Mutual flammabiHty apparatus (13,14). Unlike the Cone or OSU calorimeters this test allows the measurement of flame spread as weU as heat release and smoke. A unique feature is that it uses oxygen concentrations higher than ambient to simulate back radiation from the flames of a large-scale fire. 

Unfilled Teflon PFA has been tested in mechanical appHcations using Teflon FEP-100 as a control (24). Tests were mn on molded thmst bearings at 689.5 kPa (100 psi) against AISI 1080, Rc 20,16AA steel, and at ambient conditions in air without lubrication. A limiting PV value of 5000 was found. Wear factors and dynamic coefficients of friction are shown in Table 4. 

Fuel economy, typically expressed as distance driven per volume of fuel consumed, ie, ia km/L (mi/gal), is measured over two driving cycles specified by the Federal Test Procedure (63). Oae cycle simulates city driving and consists of relatively low speed (- 32 km/h) driving, and iacludes a portion where the car starts after having equiUbrated at ambient conditions for 16 hours. The second simulates highway driving conditions and iacludes higher speeds and... 

In general, textile materials are moisture- and temperature-sensitive. As a result, all tests should be performed at ambient conditions of 21°C and 65% relative humidity unless otherwise stated. Most of the testing procedures discussed for textile materials are available in the Hterature (1,2). 

Handling and Storage. Cyanamide solution dimerizes to dicyandiamide and urea with the evolution of heat and a gradual increase in alkalinity accelerating the reaction. Storage above 30°C without pH stabilizer leads to excessive dimerization and can result in violent exothermic polymerization. Cyanamide should be stored under refrigeration and the pH tested periodically. Stabilized cyanamide can be kept at ambient temperature for a few weeks. 

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. 

These tests must encompass the complete interlock system, from the measurement devices through the final control elements. Merely simulating inputs and checking the outputs is not sufficient. The tests must duplicate the process conditions and operating environments as closely as possible. The measurement devices and final control elements are exposed to process and ambient conditions and thus are usually the most hkely to fail. Valves that remain in the same position for extended periods of time may stick in that position and not operate when needed. The easiest component to test is the logic however, this is the least hkely to fail. 

Impact testing is not required if the design temperature is helow —29 C (—20 F) hut at or above —46 C (—50 F) and the maximum operating pressure of the fabricated or assembled components will not exceed 25 percent of the maximum allowable design pressure at ambient temperature and the combined longitudinal stress due to pressure, deadweight, and displacement strain (see Par. 319.2.1) does not exceed 41 MPa (6000 Ibfiin ). 

Biological sui veys should be used together with whole-effluent and ambient toxicity testing, and chemical-specific analyses to assess the attainment/nonattainment of designated aquatic hfe uses in state water-quahty standards. ... 

Example 2 LNG Dispersion Tests Britter and McQnaid (1988, p. 70) report on the Burro LNG dispersion tests. Compute the distance downwind from the following LNG release to obtain a concentration equal to the lower flammability limit (LFL) of 5 percent vapor concentration by volume. Assume ambient conditions of 298 K and 1 atm. The following data are available ... 

For tests at ambient temperatures, the tests should be conducted at the highest temperature anticipated for stagnant storage in summer mouths. This temperature maybe as high as 40 to45°C (104 to II3°F) in some localities. The variation in temperature shoiild be reported also (e.g.,40°C 2°C). 

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