Surface temperature generation during drop weight mechanical impact and the usefulness of dynamic thermocouple measurements for predicting impact ignition of flammable gases

Journal article


Ingram, JM, Averill, AF, Holborn, PG, Battersby, P and Benson, CM (2018). Surface temperature generation during drop weight mechanical impact and the usefulness of dynamic thermocouple measurements for predicting impact ignition of flammable gases. Journal of Loss Prevention in the Process Industries. 55, pp. 10-18.
AuthorsIngram, JM, Averill, AF, Holborn, PG, Battersby, P and Benson, CM
Abstract

The ignition of flammable atmospheres from hot surfaces arising from mechanical interactions has been a significant cause of many industrial and mining explosions. An investigation of the surface temperature generation resulting from sliding friction during short duration mechanical impacts has been carried out and the nature and usefulness of dynamic thermocouple measurement examined in the context of predicting mechanical ignition. The experimental results reveal that there is only a limited relationship between the measured maximum temperatures and the tangential energy loss during an impact. This appears to be mostly due to variation of the extent to which the tangential energy loss represents frictional loss (associated with tip sliding) rather than material deformation. Whilst an increase in impact energy tends to raise the measured surface temperature, there is significant random variation under nominally similar conditions. It is considered that this is associated with the randomness and changing nature of the contacting areas. During the small time-period of a mechanical impact, there is insufficient time for any equalisation of temperature between neighbouring contact zones to take place. With reference to the ignition of flammable gases brought about by mechanical impact, surface temperatures measured by dynamic thermocouple appear to offer only limited predictive usefulness since they could be associated with contact areas of insufficient size to transfer enough energy into the gas mixture to cause ignition. Finger-marking impact surfaces has the effect of greatly reducing the frictional energy loss but this is not fully reflected in the measured maximum surface temperature. It is concluded that ignition prediction should still be based on tests conducted with mechanical impacts taking place in an ambient flammable atmosphere.

Keywordsmechanical ignition; energy loss; surface temperature; surface contamination; impact velocity; 0904 Chemical Engineering; Strategic, Defence & Security Studies
Year2018
JournalJournal of Loss Prevention in the Process Industries
Journal citation55, pp. 10-18
PublisherLondon South Bank University
Digital Object Identifier (DOI)doi:10.1016/j.jlp.2018.05.015
Publication dates
Print26 May 2018
Publication process dates
Deposited31 May 2018
Accepted23 May 2018
Accepted author manuscript
License
CC BY-NC-ND 4.0
Permalink -

https://openresearch.lsbu.ac.uk/item/86qww

Accepted author manuscript

  • 6
    total views
  • 0
    total downloads
  • 2
    views this month
  • 0
    downloads this month

Related outputs

An analysis of civil aviation industry safety needs for the introduction of liquid hydrogen propulsion technology
Benson, CM, Ingram, JM, Battersby, PA, Mba, D, Sethi, V and Rolt, AM (2019). An analysis of civil aviation industry safety needs for the introduction of liquid hydrogen propulsion technology. TURBO EXPO Turbomachinery Technical Conference & Exposition. Phoenix AZ, USA 18 - 20 Jun 2019
Causes, Consequences and Prevention of Refrigeration Fires in Residential Dwellings
Beasley, M, Holborn, P, Ingram, J and Maidment, G (2018). Causes, Consequences and Prevention of Refrigeration Fires in Residential Dwellings. Fire Safety Journal. 102, pp. 66-67.
A comparison study into low leak rate buoyant gas dispersion in a small fuel cell enclosure using plain and louvre vent passive ventilation schemes
Ghatauray, TS, Ingram, JM and Holborn, PG (2018). A comparison study into low leak rate buoyant gas dispersion in a small fuel cell enclosure using plain and louvre vent passive ventilation schemes. International Journal of Hydrogen Energy.
Chemochromic Pd-V2O5 Sensors for Passive Hydrogen Detection in Nuclear Containments
O'Hara, R, Holborn, PG, Ingram, JM, Ball, J, Rathbone, P and Edge, R (2018). Chemochromic Pd-V2O5 Sensors for Passive Hydrogen Detection in Nuclear Containments. 2018 WM Symposia, Nuclear and Industrial Robotics, Remote Systems and Other Emerging Technologies. Phoenix, Arizona, USA 18 - 22 Mar 2018 London South Bank University.
Application of Bayesian methods and networks to ignition hazard event prediction in nuclear waste decommissioning operations
Averill, AF, Ingram, JM, Holborn, PG, Battersby, P and Benson, CM (2018). Application of Bayesian methods and networks to ignition hazard event prediction in nuclear waste decommissioning operations. Process Safety and Environmental Protection. 116, pp. 396-404.
Identification of ignition sources in high pressure enriched gaseous oxygen system incidents using flow chart road map diagram methodology
Benson, CM and Ingram, JM (2018). Identification of ignition sources in high pressure enriched gaseous oxygen system incidents using flow chart road map diagram methodology. Process Safety and Environmental Protection. 114, pp. 206-218.
Potential hazard consequences to personnel exposed to the ignition of small volumes of weakly confined stoichiometric hydrogen/air mixture
Averill, A, Ingram, J, Gomez-Augustina, L, Holborn, P, Battersby, P and Benson, CM (2018). Potential hazard consequences to personnel exposed to the ignition of small volumes of weakly confined stoichiometric hydrogen/air mixture. International Journal of Hydrogen Energy. 43 (50), pp. 22733-22745.
An experimental and CFD study into the dispersion of buoyant gas using passive venting in a small fuel cell enclosure
Ghatauray, T, Ingram, JM and Holborn, PG (2016). An experimental and CFD study into the dispersion of buoyant gas using passive venting in a small fuel cell enclosure. IChemE Hazards 26. Edinburgh 24 - 26 May 2016 London South Bank University.
A comparison study into low leak rate buoyant gas dispersion in a small fuel cell enclosure using plain and louvre vent passive ventilation schemes.
Ghatauray, T, Ingram, JM and Holborn, PG (2017). A comparison study into low leak rate buoyant gas dispersion in a small fuel cell enclosure using plain and louvre vent passive ventilation schemes. HYSAFE: International Conference On Hydrogen Safety. Hamburg, Germany 11 - 13 Sep 2017 London South Bank University.
Ignition of flammable atmospheres by mechanical stimuli
Ingram, JM (2016). Ignition of flammable atmospheres by mechanical stimuli. hazardex: Journal for Hazardous Area Environment.
Characterising the performance of hydrogen sensitive coatings for nuclear safety applications
O'Hara, R, Ingram, JM, Holborn, PG, Ball, J, Edge, R and Rathbone, P (2017). Characterising the performance of hydrogen sensitive coatings for nuclear safety applications. International Conference on Hydrogen Safety (ICHS 2017). Hamburg, Germany 11 - 13 Sep 2017 London South Bank University.
Dispersion of VOC vapours in the surface treatment workspace: influence of variability in diffusivity, mass transfer and air velocity.
Hilborne, V and Averill, AF (2016). Dispersion of VOC vapours in the surface treatment workspace: influence of variability in diffusivity, mass transfer and air velocity. Transactions of the IMF. 94 (1), pp. 24-31.
Energy losses during drop weight mechanical impacts with special reference to ignition of flammable atmospheres in nuclear decommissioning: theory and determination of experimental coefficients for impact analysis and prediction
Averill, AF, Ingram, JM, Holborn, PG and Battersby, P (2017). Energy losses during drop weight mechanical impacts with special reference to ignition of flammable atmospheres in nuclear decommissioning: theory and determination of experimental coefficients for impact analysis and prediction. International Journal of Impact Engineering. 109, pp. 92-103.
Fire suppression systems in aircraft: Their past, present & future
Benson, CM, Fernandez-Cerezo, G, Holborn, PG and Mba, D (2016). Fire suppression systems in aircraft: Their past, present & future. Fire Investigation. 1 (3), pp. 34-41.
Domestic Refrigerator Design -Safety Issues and Opportunities
Beasley, M, Holborn, PG, Ingram, JM and Maidment, GG (2017). Domestic Refrigerator Design -Safety Issues and Opportunities. The Institute of Refrigeration Event 2nd March 2017. London South Bank University 02 - 02 Mar 2017 London South Bank University.
The development of a model for the prediction of polymer spontaneous ignition temperatures in high pressure enriched oxygen across a range of pressures and concentrations
Benson, CM, Bishop, AM, Ingram, JM, Phillips, R and Nolan, PF (2016). The development of a model for the prediction of polymer spontaneous ignition temperatures in high pressure enriched oxygen across a range of pressures and concentrations. Journal of Loss Prevention in the Process Industries. 44 (Nov), pp. 369-379.
Challenges for the development of EFFICIENT - An Environmentally Friendly Fire Suppression System for Cargo using Innovative Green Technology
Fernandez-Cerezo, G, Benson, CM, Holborn, PG and Mba, D (2016). Challenges for the development of EFFICIENT - An Environmentally Friendly Fire Suppression System for Cargo using Innovative Green Technology. Institute of Fire Engineers RE16. Birmingham Nov 2016 London South Bank University.