The determination of burning velocity is very important for the calculations used in hazardous waste explosion protection and fuel tank venting, which has a direct impact on environmental protection. The scope of the present study encompass an extensive study to map the variations of the laminar burning velocity and the explosion index of LPG-air and propane-air mixtures over wide ranges of equivalence ratio ( = 0.7 to 2.2) and initial temperature (Ti = 295 to 400 K) and pressure (Pi= 50 to 400 kPa). For that purpose a cylindrical combustion bomb was developed. The reliability and accuracy of the built up facility together with calculation algorithm are confirmed by comparing the values of the laminar burning velocity obtained for a standard fuel (propane at NPT) with those available in the literature. The burning velocity was determined using different models depending on the pressure history (P-t) of the central ignition combustion process at the minimum ignition energy.
It is found that, propane exhibits higher pressure dependency than that of LPG. The maximum laminar burning velocity found for propane is nearly 455 mm/s at phi=1.1, while that for LPG is nearly 432 mm/s at 4.5% fuel percent. The maximum explosion index, commonly called the “explosion severity parameter”, is calculated from the determined laminar burning velocity and is found to be 93 bar m/s for propane, and nearly 88 bar m/s for LPG. |
