| Measurements of soot concentration, flame temperature and flame geometry have been recorded for non-smoking methane-air laminar diffusion flames at pressures from P = 1.5 MPa to P = 6.0 MPa. Soot concentration and temperature profiles were obtained using the spectral soot emission diagnostic method and the Abel inversion deconvolution technique. Visual inspection and measurement of the flame revealed a slight increase in height and decrease in cross-section with increasing pressure. Soot volume fraction increased with pressure according to fv max ∝ P1.4 for 1.5 ≤ P ≤ 5.0 MPa. The maximum carbon conversion to soot was related to pressure following the relationship eta s,max ∝ P0.55 for 1.5 ≤ P ≤ 5.0 MPa. The maximum value of carbon converted to soot was etas,max = 10.1% at P = 5.0 MPa. The maximum soot concentration was always found at a height approximately half way between the burner and the flame tip. The temperature was lower in high soot loading regions of the flame. For the same height in the flame, temperature decreased with increasing pressure. |
