A generalized method is presented for vaporization and combustion of multiple-droplet arrays, liquid films, pools, and streams. Conditions are explained for the existence of a mass flux potential function that is independent of fuel type and scalar boundary conditions and satisfies the three-dimensional Laplace's equation. Gas-phase properties, composition, and flame location are functions only of the potential function, specified scalar boundary conditions, and fuel type. Variable properties are considered. Flame stand-off distances for liquid interfaces near wet-bulb temperatures are predicted more accurately with variable properties. Flame location and transport properties are found for decane, heptane, and methanol fuels, with different ambient conditions. The analysis also applies to vaporization without combustion and to combustion with transient liquid-phase heating. (c) 2005 Elsevier Ltd. All rights reserved.