Minimizing Sampling Loss in Trace Gas Emission Measurements for Aircraft Engines by Using a Chemical Quick-Quench Probe

Author(s):  
Elena de la Rosa Blanco ◽  
Jay Peck ◽  
Richard C. Miake-Lye ◽  
Frank B. Hills ◽  
Ezra C. Wood ◽  
...  

This paper describes the development and testing of a gas sampling probe that quenches chemical reactions by using supersonic expansion and helium dilution. Gas sampling probes are required for accurate measurement of exhaust emissions species, which is critical to determine the performance of an aircraft engine. The probe was designed through rounds of computational modeling and laboratory testing and was subsequently manufactured and then tested at the University of Tennessee Space Institute behind a General Electric J85 turbojet engine at different power settings: idle, maximum military, and afterburning. The experimental test results demonstrated that the chemical quick-quench (CQQ) probe suppressed the oxidation of carbon monoxide (CO) inside the probe system and preserved more CO at afterburning conditions. In addition, the CQQ probe prevented hydrocarbons from being partially oxidized to form CO at idle powers and measured higher hydrocarbons and lower CO emission compared with a conventional probe at that low power condition. The CQQ probe also suppressed nitrogen dioxide (NO2) to nitric oxide (NO) conversion through all engine power settings. These data strongly support the conclusion that the CQQ probe is able to quench unwanted chemical reactions inside the probe for all engine power levels.

Author(s):  
Elena de la Rosa Blanco ◽  
Jay Peck ◽  
Richard C. Miake-Lye ◽  
Frank B. Hills ◽  
Ezra C. Wood ◽  
...  

This paper describes the development and testing of a gas sampling probe that quenches chemical reactions by using supersonic expansion and helium dilution. Gas sampling probes are required for accurate measurement of exhaust emissions species, which is critical to determine the performance of an aircraft engine. The probe was designed through rounds of computational modeling and laboratory testing, and was subsequently manufactured and then tested at the University of Tennessee Space Institute (UTSI) behind a General Electric J85 turbojet engine at different power settings: idle, maximum military and afterburning. The experimental test results demonstrated that the Chemical Quick-Quench (CQQ) probe suppressed the oxidation of carbon monoxide (CO) inside the probe system and preserved more CO at afterburning conditions. In addition, the CQQ probe prevented hydrocarbons from being partially-oxidized to form CO at idle powers, and measured higher hydrocarbons and lower CO emission compared to a conventional probe at that low power condition. The CQQ probe also suppressed nitrogen dioxide (NO2) to nitric oxide (NO) conversion through all engine power settings. These data strongly support the conclusion that the CQQ probe is able to quench unwanted chemical reactions inside the probe for all engine power levels.


Analisis ◽  
2020 ◽  
Vol 19 (1) ◽  
pp. 76-84
Author(s):  
Nasarius Aban ◽  
Gabriel Tanusi

This study aims to determine the effect of emotional intelligence, independent attitude and family environment on the interest in entrepreneurship at the University of Flores Management Faculty of Economics. This research is an associative research. The population in this study were students of the Management Study Program of the Faculty of Economics of the University of Flores in the class of 2015-2016 who had passed the entrepreneurship courses of 170 people. Samples taken in this study were 105 respondents, with sampling techniques using simple random sampling. Data collection using questionnaires and interviews, while data analysis was performed using multiple linear regression analysis. The results of multiple regression analysis are Y = 1.060 + 0.594X1 + 0.114X2 + 0.421X3 + e. The coefficient of determination R2 for the variables X1, X2, X3 is 0.675, which means that entrepreneurial interest can be influenced by emotional intelligence, independent attitude and family environment by 67.50% and the remaining 32.50% is influenced by other factors including factors of education, skills, motivation and others. F test results show the value of Fcount> Ftable (28.442> 2.69) with a significant level of 0.000 <0.05 meaning that there is a positive and significant influence between emotional intelligence, independent attitude and family environment together on the entrepreneurial interest of the Faculty of Management Study Program Students The economy. Partial test results (t) show 1) Emotional intelligence factors have a positive and significant effect on entrepreneurial interest 2) Family environment factors have a positive and significant effect on entrepreneurial interest 3) Independent attitude factor has no positive and significant effect on entrepreneurial interest.


2020 ◽  
Vol 10 (1) ◽  
pp. 235-244
Author(s):  
Elena A. M. Gandini ◽  
Tania Horák

AbstractThis contribution reports on the developing and piloting of a computer-based version of the test of English as a foreign language produced by the University of Central Lancashire (UCLan), where it is currently used for the admission of international students and the subsequent evaluation of their language progress. Among other benefits, computer-based testing allows for better and individualised feedback to both teachers and students, and it can provide a more authentic test experience in light of the current digital shift that UK universities are undergoing. In particular, the qualitative improvement in the feedback available for test-takers and teachers was for us a crucial factor. Providing students with personalised feedback, that is, directly linked to their performance, has positive washforward, because it means we can guide their future learning, highlighting the areas they need to work on to improve their language skills and giving them suggestions on how to succeed in academia. Furthermore, explaining the meaning of test results in detail improves transparency and ultimately washback, as teachers can use the more accessible marking criteria, together with information on how their students performed, to review plans and schemes of work for subsequent courses.


Author(s):  
Takeshi Yamamoto ◽  
Kazuo Shimodaira ◽  
Seiji Yoshida ◽  
Yoji Kurosawa

The Japan Aerospace Exploration Agency (JAXA) is conducting research and development on aircraft engine technologies to reduce environmental impact for the TechCLEAN project. As a part of the project, combustion technologies have been developed with an aggressive target that is an 80% reduction over the NOx threshold of the ICAO CAEP/4 standard. A staged fuel nozzle with a pilot mixer and a main mixer was developed and tested using a single-sector combustor under the target engine’s LTO cycle conditions with a rated output of 40 kN and an overall pressure ratio of 25.8. The test results showed a 77% reduction over the CAEP/4 NOx standard. A reduction in smoke was found under a higher thrust condition than the 30% MTO condition, and a reduction in CO emission was found under a lower thrust condition than the 85% MTO condition. In the present study, an additional fuel burner was designed and tested with the staged fuel nozzle in a single-sector combustor to control emissions. The test results show that the combustor enables an 82% reduction in NOx emissions relative to the ICAO CAEP/4 standard and a drastic reduction in smoke and CO emissions.


1972 ◽  
Vol 37 (2) ◽  
pp. 222-228 ◽  
Author(s):  
Duane H. King ◽  
Danny E. Olinger

AbstractIn the spring of 1783, Oconastota, the Great Warrior and principal chief of the Overhill Cherokees, died and was buried at his beloved town of Chota on the Little Tennessee River in present day Monroe County, Tennessee. In the fall of 1969, the Department of Anthropology of the University of Tennessee, while conducting archaeological investigations at this site, disinterred a burial which exhibits striking correlations with the historic accounts of Oconastota and his inhumation.


2018 ◽  
Vol 30 (2) ◽  
pp. 329-332 ◽  
Author(s):  
Gordon Ehrensing ◽  
Linden E. Craig

We evaluated 134 cutaneous plasmacytomas in 125 dogs submitted to the University of Tennessee surgical biopsy service between 2009 and 2012 to determine whether the presence of intravascular neoplastic cells had prognostic significance. Tumors occurred in middle-aged to geriatric dogs (range: 5–16 y, mean: 9.6 y) and most frequently involved the skin of the head and distal limbs. Diagnoses were made based on light microscopy, and in some cases confirmed by immunoreactivity of neoplastic cells for MUM1. Tumors were categorized as having or not having intravascular neoplastic cells within sections examined. The intravascular location of tumor cells was confirmed by immunoreactivity of endothelial cells for factor VIII–related antigen in 3 cases. Neoplastic cells within vessel lumens were identified in 20 of 125 dogs (16%). Submitting veterinary practices were contacted for follow-up data on patients including local recurrence and cutaneous plasmacytomas in other locations. Follow-up information was acquired on 99 dogs (79%). Recurrence was documented in one dog with cutaneous plasmacytomas; both masses had incomplete margins and intravascular neoplastic cells. Additional distant cutaneous plasmacytomas were later diagnosed in 3 patients; none of these dogs had intravascular neoplastic cells. In no cases were cutaneous plasmacytomas suspected to be a cause of death or reason for euthanasia. Intravascular neoplastic cells were more common in tumors of the distal limbs (36%) compared to other locations (11%; p = 0.0007). The presence of intravascular neoplastic cells did not affect prognosis in cutaneous plasmacytomas.


Sign in / Sign up

Export Citation Format

Share Document