University of Illinois Chicago

The High Pressure Single Pulse Shock Tube Laboratory at UIC

The High Pressure Shock Tube lab at UIC houses a state of the art High Pressure Shock Tube having a driven section length of 100-160” and diameter 1” which can be operated at high pressures varying from 15-1000 atm. The operating temperatures attained can be from 600 K to 2000 K. The inert gases used are Ar and He and the shock tube employs diaphragms made of aluminum and brass.

For complementary studies the Lab is also has a Low Pressure Shock tube operating at pressures from 0.1-15 atm and attaining temperatures up to 2000 K. The Driven Section length is 120” and diameter is 4” and uses Mylar diaphragms.

High pressure shock tube facility, 15-1000 bar, foreground Lower pressure shock tube facility, 0.1 -15 bar, background

The shock tubes are used to produce normal shocks in test gases to instantaneously raise the pressure and temperature of the test gas for a fixed but adjustable amount of time. The effect of high temperatures and pressures on the chemical reactions taking place in the test gas is studied by withdrawing samples from the shock tube and examining the chemical composition by using gas chromatography. The Lab is equipped with five sophisticated Gas Chromatographs outfitted with different types of capillary columns which allow detection and quantification of hydrocarbons, oxygenates, nitrites, sulfuric compounds, permanent gases and several other compounds using Thermal Conductivity Detectors (TCD), Flame Ionization Detectors (FID) as well as a two dimensional gas chromatograph attached to an ultramodern LECO GC-Time of Flight (TOF) instrument.

Gas Chromatographs:

Agilent Technologies 7890B (2 FIDs)
Agilent Technologies 7890B (TCD+ FID with Ni-Cat)
Agilent Technologies 7890A (FID + TCD with Ni-Cat)
Hewlett-Packard 6890 (2 FIDs)
Hewlett-Packard 6890 (FID + TCD + Ni-Cat)

One of the 7890 Gas Chomatographs
LECO Pegasus 4D with two dimensional gas chromatography and time of flight mass spectrometry. Lower pressure and high pressure shock tubes in the background.

These latest instruments coupled with years of experience in gas chromatography/mass spectrometry allow us to carry out cutting-edge chemical kinetic research on fuel pyrolysis and oxidation. Current projects include:

  • Air Force Office of Scientific Research: Pyrolysis and Oxidation studies of Real Jet Fuels.
  • Army Research Office: A New Approach to the Combustion Chemistry of Low Cetane Number Jet Fuels
  • Army Research Lab: Chemical Identifiers of Army Relevant Fuels
  • National Science Foundation: High Pressure Ring Contraction of Cyclic Hydrocarbons

The High Repetition Rate Shock Tube Laboratory at UIC

The HRRST Laboratory at UIC houses a miniature shock tube having a driven section of diameter 12.7mm. The HRRST can be operated at pressures up to 100 bar and at a cycle rate of about 1 Hz. The main advantages are in the ability to quickly sweep out a wide range of experimental conditions and to repeatedly access conditions as needed to measure weak signals. The HRRST is used for a variety of experimental measurements including high temperature ignition delay, time-resolved species concentrations measured with tunable diode laser spectroscopy, and even high temperature fluid mechanic measurements using synchrotron sourced techniques.

High Repetition Rate Shock Tube

Besides the miniature shock tube, the laboratory houses a high temperature/high pressure uniform gas cell, a 1000 psi strand burner used for propellant and energetic materials testing, and the miniature rapid compression machine currently in development.

Diagnostic Equipment and Capabilities:

  • Tunable diode lasers: 2x CO, CH2O, H2O, I, HF, and suitable detectors.
  • Optical spectrum analyzer
  • Custom spectrometer with high speed line detectors and ccd cameras, and various light sources.
  • Product gas sampling

Current projects include:

  • Army Research Lab: Time-resolved formaldehyde measurements during ignition and combustion of Army Relevant Fuels
  • Department of Energy/EERE: MISR: Miniature Ignition Screening Rapid Compression Machine for Kinetic Measurements of Novel Fuels
  • National Science Foundation: CAREER: Energetic Radical Reactions and Impact on High and Low Pressure Combustion