Purifying Air in Future Metro Trains: A Challenge for Our Researchers
ESTACA’s teacher-researchers are conducting an experimental study for Alstom, on a full-scale model of a metro train, installed on the aeraulic and climatic test bench at the Centre d’Essais Ferroviaire (CEF) in Valenciennes. The goal is to characterize air quality and determine the efficiency of air filtration and purification systems inside a car.
Air quality in Underground Rail Enclosures (EFS) has been a matter of concern for several years. Studies measuring air quality in EFS have revealed high levels of suspended particulate matter, with concentrations of fine particles higher than those observed in the outdoor air. These particles get into the trains through the ventilation systems and various openings, with health consequences for passengers.
Alstom wants to understand the dynamics of particles in carriages, and study systems for cleaning the air inside its new trains. The company entrusted the technical study to ESTACA: design the pollution-generating device, measurements, analysis of results and recommendations.
Evaluating carriage air filtration systems
Alstom produced a full-scale model of a carriage with an air-conditioning system designed in-house and loaned it to the Valenciennes CEF.
Teacher-researchers in the Air Quality Division developed innovative solutions for generating a controlled polluted atmosphere and for taking stable, reproducible measurements throughout the volume of the carriage. They wanted to characterize particle dynamics throughout the carriage and evaluate various air purification solutions and apply them in the train-scale model.
They designed a complete system with a mini-chamber and a network of sensors that measure concentrations of fine and ultrafine particles.
Then they reproduced a concentration of particulate pollutants representative of the railway enclosure environment using a synthetic particle generator.
A series of measurements with purification and/or filtration systems installed in the HVAC (Heating, Ventilation, and Air Conditioning) system were designed to assess filtration efficiency.
Evaluating carriage air filtration systems
Alstom produced a full-scale model of a carriage with an air-conditioning system designed in-house and loaned it to the Valenciennes CEF.
Teacher-researchers in the Air Quality Division developed innovative solutions for generating a controlled polluted atmosphere and for taking stable, reproducible measurements throughout the volume of the carriage. They wanted to characterize particle dynamics throughout the carriage and evaluate various air purification solutions and apply them in the train-scale model.
They designed a complete system with a mini-chamber and a network of sensors that measure concentrations of fine and ultrafine particles.
Then they reproduced a concentration of particulate pollutants representative of the railway enclosure environment using a synthetic particle generator.
A series of measurements with purification and/or filtration systems installed in the HVAC (Heating, Ventilation, and Air Conditioning) system were designed to assess filtration efficiency.
Positive initial results could lead to further studies
The results of the study conducted by ESTACA researchers confirmed the design of the polluted atmosphere creation device, assessed filtration efficiencies and visualized particle distribution. These results will enable Alstom’s teams to continue developing air purification systems and adjusting their models.
