Tommy Tzanetakis

Knock limit prediction via multi-zone modelling of a primary reference fuel HCCI engine

A multi-zone model was used to predict the combustion behaviour of a single cylinder Homogeneous Charge Compression Ignition (HCCI) engine. Blow-by was considered to capture engine performance at the low operating speed of 700 rpm. The model was calibrated and verified by matching predicted and experimental pressure traces at two engine operating points. The calculated CO and Unburned Hydrocarbon (UHC) emissions showed good agreement with experiments at both points. The onset of knock during HCCI was adequately reproduced using the Maximum Pressure Rise Rate (MPRR) criterion and another method based on the pressure equalisation rate within the charge.

Optical absorption measurements of hydrogen chloride at high temperature and high concentration in the presence of water using a tunable diode laser system for application in pyrohydrolysis non-ferrous industrial process control.

A tunable diode laser (TDL) was used to measure hydrogen chloride (HCl) spectra at 5747 cm−1 (1.74 μm) and temperatures of 25–950 °C in a quartz cell. The purpose was to evaluate the capability of monitoring HCl concentration under pyrohydrolysis conditions using a near-infrared (NIR) laser. These conditions are characterized by 20–40% HCl, 2–40% H2O, and the presence of metal chloride vapors at temperatures of 600–1000 °C. Spectral peak area measurements of HCl–N2 mixtures at atmospheric pressure and a path length of 8.1 cm showed linear absorption behavior between concentrations of 5–95% and temperatures of 25–950 °C. Results from the addition of 2–40% water (H2O) indicate that the HCl peak area relationships are not affected for temperatures of 350–950 °C. Evaporating NiCl2 within the cell did not show spectral interference effects with HCl between 650 and 850 °C. The results from this work indicate that a near-infrared optical sensor is capable of measuring high HCl concentrations at high temperatures in the presence of high H2O content during pyrohydrolysis process conditions.