IGNITION- Thermo-fluid dynamic studies on rapid compression of oxygen gas in piping systems

The project at a glance

Start date:

01 Sep 2019
Duration in months:

36
Funding:

FNR, Rotarex S.A
Principal Investigator(s):

Stephan LEYER

About

The project idea is to investigate, assess, and understand enriched high-pressure oxygen (EHPO) flows and their associated thermo-fluid dynamics (TFD) in Rotarex’s pressure regulators (PRs) installed in industrial piping (henceforth ‘PR-piping’). The PR reduces EHPO’s pressure to be used in welding, cutting, heating, healthcare, and other applications. A shut-off valve (SOV) typically controls oxygen flow to high pressure (HP) side of the PR (see Fig. 1). Upon opening the SOV, EHPO flows and gets adiabatically compressed at the HP end of the PR producing a rapid pressure-temperature (P-T) surge. This, combined with the properties of EHPO (e.g. high oxidizing ability) and PR-piping components (e.g. low ignition threshold in EHPO atmosphere) has caused many ignition events. Compressed oxygen flow after the SOV opening is turbulent and produces shock waves traveling at supersonic speeds resulting in a wide range of flow phenomena that have not yet been subjected to rigorous scientific investigations.

The project aims to experimentally investigate EHPO flow and its TFD phenomena in a PR-piping prototype. An oxygen test facility equipped with advanced sensors will be built for this purpose during the project at the University of Luxembourg (UL). Upon completion, initial tests will be performed using inert gases (e.g. argon) to assess the working of the facility and to calibrate the sensors followed by EHPO experiments. Studies to assess the effect of inlet pressure, SOV opening speed, and the SOV-PR pipe length on the flow behavior will be performed. Experimental data will be analyzed to understand the flow phenomena induced by the pressure shocks and adiabatic compression.