title: Flow Rates Measurement and Uncertainty Analysis in Multiple-Zone Water-Injection Wells from Fluid Temperature Profiles.
abstract: This work is a contribution to the development of flow sensors in the oil and gas industry. It presents a methodology to measure the flow rates into multiple-zone water-injection wells from fluid temperature profiles and estimate the measurement uncertainty. First, a method to iteratively calculate the zonal flow rates using the Ramey (exponential) model was described. Next, this model was linearized to perform an uncertainty analysis. Then, a computer program to calculate the injected flow rates from experimental temperature profiles was developed. In the experimental part, a fluid temperature profile from a dual-zone water-injection well located in the Northeast Brazilian region was collected. Thus, calculated and measured flow rates were compared. The results proved that linearization error is negligible for practical purposes and the relative uncertainty increases as the flow rate decreases. The calculated values from both the Ramey and linear models were very close to the measured flow rates, presenting a difference of only 4.58 m³/d and 2.38 m³/d, respectively. Finally, the measurement uncertainties from the Ramey and linear models were equal to 1.22% and 1.40% (for injection zone 1); 10.47% and 9.88% (for injection zone 2). Therefore, the methodology was successfully validated and all objectives of this work were achieved.
authors.affiliation: Laborat&#243;rio de Avalia&#231;&#227;o e Medi&#231;&#227;o em Petr&#243;leo, Departamento de Engenharia de Computa&#231;&#227;o e Automa&#231;&#227;o, Universidade Federal do Rio Grande do Norte, Natal 59072970, Brazil. jose_edenilson@yahoo.com.br.
authors.forename: José E O
authors.initials: JE
authors.lastname: Reges
authors.affiliation: Laborat&#243;rio de Avalia&#231;&#227;o e Medi&#231;&#227;o em Petr&#243;leo, Departamento de Engenharia de Computa&#231;&#227;o e Automa&#231;&#227;o, Universidade Federal do Rio Grande do Norte, Natal 59072970, Brazil. andres@dca.ufrn.br.
authors.forename: A O
authors.initials: AO
authors.lastname: Salazar
authors.affiliation: Laborat&#243;rio de Automa&#231;&#227;o em Petr&#243;leo, Departamento de Engenharia de Petr&#243;leo, Universidade Federal do Rio Grande do Norte, Natal 59072970, Brazil. carlamaitelli@gmail.com.
authors.forename: Carla W S P
authors.initials: CW
authors.lastname: Maitelli
authors.affiliation: Laborat&#243;rio de Automa&#231;&#227;o em Petr&#243;leo, Departamento de Engenharia de Petr&#243;leo, Universidade Federal do Rio Grande do Norte, Natal 59072970, Brazil. lucas.gdcarvalho@bct.ect.ufrn.br.
authors.forename: Lucas G
authors.initials: LG
authors.lastname: Carvalho
authors.affiliation: Laborat&#243;rio de Automa&#231;&#227;o em Petr&#243;leo, Departamento de Engenharia de Petr&#243;leo, Universidade Federal do Rio Grande do Norte, Natal 59072970, Brazil. ursulabritto@gmail.com.
authors.forename: Ursula J B
authors.initials: UJ
authors.lastname: Britto
keywords: flow sensors; measurement uncertainty; multiple-zone water-injection wells; oil and gas industry; wellbore heat transmission