The equilibrium flammability envelopes of turbine fuels were determined by both visual and instrumental techniques. The lean and rich limits were found to be linear functions of altitude and temperature when wall effects were reduced and ignition spark energies were high. The linearity of the limits could be altered by increasing the wall effects or decreasing the ignition spark energies. Wide-cut turbine engine fuels, aviation kerosenes and blends of the two types were tested. The flammability characteristics of the fuels at equilibrium were compared to those of the fuel under simulated aircraft dynamic conditions. Aircraft dynamics affect fuel primarily by producing spray. When the point of ignition was not directly within the sprayed fuel, no deviation from the normal equilibrium flammability envelope occurred. When the point of ignition was directly within the spray, the lean flammability limit of the fuel was extended considerably beyond the equilibrium limit. (Author)
展开▼
