A novel experimental approach is developed to measure the downward spreading flame velocity over the thermally thin ashless filter paper (cellulose). A motion control system is developed with a thermocouple as the sensor and it converts the downward spreading flame into a stationary flame using a PID controller. The set up is called the flame tracker. Different refinement of the flame tracker algorithm has been tested in this work. Flame spread rate and the flame profiles are studied using the flame tracker setup. The flame tracker results are compared to the traditional approach obtained from the digital video of the flame spread. The results establish that the stationary flame created by the flame tracker is comparable to the spreading flame. The approach using two thermocouples has been found as the best alternative.
