Nonintrusive systems for the measurement on test rigs of aeroengine exhaust emissions required for engine certification (CO, NO(x), total unburned hydrocarbon, and smoke), together with CO(2) and temperature have been developed. These results have been compared with current certified intrusive measurements on an engine test. A spectroscopic database and data-analysis software has been developed to enable Fourier-transform Infrared measurement of concentrations of molecular species. CO(2), CO, and NO data showed agreement with intrusive techniques of approximately ?30%. A narrow-band spectroscopic device was used to measure CO(2) (with deviations of less than ?10% from the intrusive measurement), whereas laser-induced incandescence was used to measure particles. Future improvements to allow for the commercial use of the nonintrusive systems have been identified and the methods are applicable to any measurement of combustion emissions.
Abstract-We report on the installation and commissioning of two systems for the measurement of cross-sectional distributions of pollutant species in jet exhaust, within the engine ground test facility at INTA, Madrid. These systems use optical tomography techniques to estimate the cross-sectional distributions of CO 2 and soot immediately behind the engine. The systems are designed to accommodate the largest civil aviation engines currently in service, without obstruction of the exhaust or bypass flows and with negligible effect upon the entrained flow behavior. We describe the physical construction and installation status of each system. In the case of the CO 2 system, we examine the challenges of achieving the structural rigidity necessary for adequate suppression of pointing error within 126 laser-based transmittance measurements, each utilizing a 7 m overall path length. We describe methods developed for efficient implementation of co-planarity and 4-degree-of-freedom alignment of individual paths within this beam array. We also present laboratory performance data for three alternative optical designs that differ in their approach to the management of pointing error and turbulence-induced beam wander and spread. The FLITES soot monitoring capability is based on laser induced incandescence (LII) and uses a short-pulse fiber laser and two CCD cameras, in an autoprojection arrangement. We describe the measurement geometry currently being implemented in the test cell and discuss optical design issues, including once again the effect of the plume itself.
31 higher level employees in 1 firm and 26 in another were assessed by objective test batteries. Clinical interpretations of test data, test scores, and other predictors were analyzed with reference to criterion personality ratings and management decisions at a follow-up point of 3* yrs for the 1st sample and 7 yrs for the 2nd. Predictive validity of test assessments was generally satisfactory in the 1st sample, although not pragmatically superior to that of certain objective data Prediction was less satisfactory in the 2nd sample, but more unique to test data. A matching study indicated some correspondence of test reports and criterion personality sketches in the 2nd sample. Uninterpreted test scores were not generally valid except as measures of intelligence. Implications of the sample differences and of the method are discussed.
Calibrated coherent anti-Stokes Raman (CARS) spectra have been recorded for the resolved Q branches of the vibrational fundamentals and first hot bands of I4N,, l4N''N and 15N, at a temperature of 1200 K. The spectra show a convolved linewidth of 0.13 cm-', and have been used to derive new values of spectroscopic constants, for the species observed, with specific reference to the position of the Q branch lines where J > 20 for u = 1-0, and J = 0-30 for u = 2-1. The critical overlap region of the fundamental and the hot band may now be computer simulated with confidence, which should be of considerable help in combustor thermometry using CARS.
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