title: Flammability limits of hydrated and anhydrous ethanol at reduced pressures in aeronautical applications.
abstract: There is interest in finding the flammability limits of ethanol at reduced pressures for the future use of this biofuel in aeronautical applications taking into account typical commercial aviation altitude (<40,000 ft). The lower and upper flammability limits (LFL and UFL, respectively) for hydrated ethanol and anhydrous ethanol (92.6% and 99.5% p/p, respectively) were determined for a pressure of 101.3 kPa at temperatures between 0 and 200°C. A heating chamber with a spherical 20-l vessel was used. First, LFL and the UFL were determined as functions of temperature and atmospheric pressure to compare results with data published in the scientific literature. Second, after checking the veracity of the data obtained for standard atmospheric pressure, the work proceeded with reduced pressures in the same temperature range. 295 experiments were carried out in total; the first 80 were to calibrate the heating chamber and compare the results with those given in the published scientific literature. 215 experiments were performed both at atmospheric and reduced pressures. The results had a correlation with the values obtained for the LFL, but values for the UFL had some differences. With respect to the water content in ethanol, it was shown that the water vapor contained in the fuel can act as an inert substance, narrowing flammability.
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Christian J R
authors.initials: CJ
authors.lastname: Coronado
authors.affiliation: São Paulo State University-UNESP, Campus of Guaratinguetá-FEG Av. Ariberto P. da Cunha, 333, Guaratinguetá, SP, CEP 12516-410, Brazil. Electronic address: joao@feg.unesp.br.
authors.forename: João A
authors.initials: JO
authors.lastname: Carvalho
authors.affiliation: National Space Research Institute-INPE, Combustion and Propulsion Laboratory-LCP Rod. Pres. Dutra, km 39, Cachoeira Paulista, SP, CEP 12630-000, Brazil.
authors.forename: José C
authors.initials: JC
authors.lastname: Andrade
authors.affiliation: São Paulo State University-UNESP, Campus of Guaratinguetá-FEG Av. Ariberto P. da Cunha, 333, Guaratinguetá, SP, CEP 12516-410, Brazil.
authors.forename: Andrés Z
authors.initials: AZ
authors.lastname: Mendiburu
authors.affiliation: National Space Research Institute-INPE, Combustion and Propulsion Laboratory-LCP Rod. Pres. Dutra, km 39, Cachoeira Paulista, SP, CEP 12630-000, Brazil.
authors.forename: Ely V
authors.initials: EV
authors.lastname: Cortez
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Felipe S
authors.initials: FS
authors.lastname: Carvalho
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Gonçalves
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Quintero
authors.affiliation: Faculty of Mechanical Engineering, Universidad Antonio Nariño, Tunja, Colombia.
authors.forename: Elkin I Gutiérrez
authors.initials: EI
authors.lastname: Velásquez
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Marcos H
authors.initials: MH
authors.lastname: Silva
authors.affiliation: National Space Research Institute-INPE, Combustion and Propulsion Laboratory-LCP Rod. Pres. Dutra, km 39, Cachoeira Paulista, SP, CEP 12630-000, Brazil.
authors.forename: José C
authors.initials: JC
authors.lastname: Santos
authors.affiliation: Federal University of Itajubá-UNIFEI, Mechanical Engineering Institute-IEM Av. BPS 1303, Itajubá, MG, CEP 37500-903, Brazil.
authors.forename: Marco A R
authors.initials: MA
authors.lastname: Nascimento
mesh_terms: D000431:Ethanol / Q000737:chemistry*; D005390:Fires; D011312:Pressure
chemical_list: D000431:Ethanol
keywords: Ethanol; Flammability limits; Pressure and temperature dependence; Visual criterion