Burning behavior of minivan passenger cars

• We conducted four full-scale fire experiments using minivan passenger cars.
• The temperatures inside the burning car and the mass loss rates were measured.
• The heat release rates (HRRs) were obtained from the mass loss rates.
• The HRR curves were characterized as a function of time by superposition of a Boltzmann curve and a Gaussian curve.

Four full-scale fire experiments using minivan passenger cars were carried out to establish the burning behavior of minivan passenger cars. The cars were ignited with 80 g of alcohol gel fuel placed at the splashguard of the right rear wheel, on the right side of the front bumper, or at the seat in the passenger compartment. We observed how the fire spread from the point of origin and investigated the effects of the location of the ignition on the burning behavior. The temperature inside the burning car and the mass loss rate were measured. The burning of a minivan was composed of three compartmental fires: the front compartment (front nose), the passenger compartment, and the rear part inclusive of the fuel. In the experiments where ignition was initiated outside the passenger compartment, depending on its location the flames spread to the compartments in the following order: rear or front (ignition point), passenger, and front or rear (opposite to the ignition point). The breaking of the window glass markedly affected the spread of fire into the passenger compartment. In the experiments where ignition was initiated at the seat of the passenger compartment, air supply from open windows was required to continue the combustion. When all the windows were closed, the combustion in the passenger compartment self-extinguished. The temperature of the passenger compartment peaked at 1094 °C. The heat release rate (HRR) curves showed several peaks depending on the burning conditions in the three compartments. The HRR increased markedly when the fire spread to several different parts of the car at the same time. The HHR peaked at 4 MW when the seat in the passenger compartment was ignited and a window was open by 20 cm. We characterized the measured HRR curves as a function of time by the superposition of Boltzmann and Gaussian curves. The HRRs of the burning cars were described by the sum of the HRRs from each compartment.