An experimental study on the spreading characteristics and burning behaviors of continuous spill fires under cross flow

Fuel leakage and spill fires often occur during storage and transportation of liquid fuels. And the spread and burning processes of spill fires are susceptible to cross-air flows. In this paper, spill fire experiments were conducted on a fireproof glass (with or without ignition) under different wind speeds (0-2 m/s). The effects of wind on the spread process and burning behaviors were analyzed. Results showed that, for the cases without ignition, the spread length could vary in a non-linear manner with wind speed. And a spread length model was developed based on force analysis. For spill fires under small wind speeds, the burning area increased firstly, followed by a decrease before stabilization. When the wind speed exceeded a critical value, the fuel layer spread rapidly in the upwind direction after the shrinking phase. The steady stage was observed for all tests. With the wind speed increase, the quasi-steady burning area changes from being circular to elliptic first, before it gradually became circular in the end. To explain this process, a detailed heat transfer analysis was conducted. Considering the fuel layer shape and the heat transfer characteristics of spill fires, an analytical burning rate model was developed.