title: Apparatus for the measurement of the speed of sound of ammonia up to high temperatures and pressures.
abstract: An apparatus for the measurement of the speed of sound based on the pulse-echo technique is presented. It operates up to a temperature of 480 K and a pressure of 125 MPa. After referencing and validating the apparatus with water, it is applied to liquid ammonia between 230 and 410 K up to a pressure of 124 MPa. Speed of sound data are presented with an uncertainty between 0.02% and 0.1%.
authors.affiliation: Lehrstuhl für Thermodynamik und Energietechnik, Universität Paderborn, Warburger Straße 100, 33098 Paderborn, Germany.
authors.forename: Frithjof H
authors.initials: FH
authors.lastname: Dubberke
authors.affiliation: Lehrstuhl für Thermodynamik und Energietechnik, Universität Paderborn, Warburger Straße 100, 33098 Paderborn, Germany.
authors.forename: David B
authors.initials: DB
authors.lastname: Rasche
authors.affiliation: Lehrstuhl für Thermodynamik und Energietechnik, Universität Paderborn, Warburger Straße 100, 33098 Paderborn, Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Baumhögger
authors.affiliation: Lehrstuhl für Thermodynamik und Energietechnik, Universität Paderborn, Warburger Straße 100, 33098 Paderborn, Germany.
authors.forename: Jadran
authors.initials: J
authors.lastname: Vrabec