ON THE VAPORIZATION AND THERMAL OXIDATION OF CHLORINATED HYDROCARBON/ALCOHOL SPRAYS

We report species concentration data obtained during the vaporization and thermal decomposition of polydisperse multicomponent chlorinated hydrocarbon (CHC)/alcohol sprays. Mixtures of 1,1,1-trichlo-roethane (C2H3Cl3) (TCA) and isopropanol (C3H7OH) are atomized in the postflame environment of a methane/air (U 0.95) flame. Species concentrations, determined by extractive Fourier transform infra-red analysis, reveal perturbations in TCA destruction and by-product species formation. The effect of isopropanol addition on by-product species concentrations is similar to previous results involving the ther-mal oxidation of TCA/alkane mixtures. TCA destruction is incomplete at injection temperatures less than 1000 K. Under these conditions, TCA/isopropanol sprays produce lower residual TCA concentrations than pure TCA sprays. Review of physical property data, numerical modeling (to be published elsewhere), and comparisons with previous experimental results for TCA/heptane and TCA/hexadecane together suggest two primary findings. First, the conventional approach of parameterizing fuel volatility by the fuel satu-ration temperature at 101.3 kPa does not correlate with the trends evident in our data. For these fuel mixtures and conditions, the latent heat of vaporization (DHv) provides a better correlation. Second, the data also suggest that, for incineration-resistant multicomponent mixtures, the molecular weights of mixture constituents may influence droplet combustion characteristics and should be considered when formulatin