Chemical Contamination Sensor for Phosphate Ester Hydraulic Fluids

The paper deals with chemical contamination monitoring in phosphate-ester-based hydraulic fluids using nondispersive infrared (NDIR) optical absorption. Our results show that NDIR monitoring allows detecting the take-up of water into such fluids and their hydrolytic disintegration as these become additionally stressed by Joule heating. Observations on the O–H stretching vibration band (3200–3800 cm−1) are used for determining the free water content (0–1.5%) and the Total Acid Number (0–1 mgKOH/g). Both quantities can be assessed by monitoring the strength and the asymmetry of the O–H vibration band with regard to the free water absorption band centered around 3500 cm−1. As such optical parameters can be assessed without taking fluid samples from a pressurized hydraulic system, fluid degradation trends can be established based on regular measurements, before irreversible damage to the fluid has occurred. Therefore maintenance actions can be planned accordingly, which is very important for the airline, as unscheduled maintenance disturbs flight organizations and often generates money loss.

• Record URL:
  http://www.hindawi.com/journals/ijae/2010/156281.html
• Authors:
  • Paul, Sumit
  • Legner, Wolfgang
  • Krenkow, Angelika
  • Muller, Gerhard
  • Lemettais, Thierry
  • Pradat, Francois
  • Hertens, Delphine
• Publication Date: 2010

Language

• English

Media Info

• Media Type: Web
• Pagination: Article ID 156281
• Serial:
  • International Journal of Aerospace Engineering
  • Volume: 2010
  • Publisher: Hindawi Publishing Corporation
  • Serial URL: http://www.hindawi.com/journals/ijae
• Publication flags:

  Open Access (libre)

Subject/Index Terms

• TRT Terms: Absorption; Biodeterioration; Chemical properties; Chemical spills; Degradation (Hydrology); Heating (Structures); Hydraulic fluids; Inspection; Maintenance; Monitoring; Thermal degradation; Thermal properties
• Uncontrolled Terms: Contamination
• Subject Areas: Aviation; Hydraulics and Hydrology; I30: Materials;

Filing Info

• Accession Number: 01226571
• Record Type: Publication
• Files: TRIS
• Created Date: Nov 17 2010 7:24AM