The development of an anemometer for industrial bread baking

Measuring airflow rate in an industrial bread-baking oven requires a sensor that is sensitive at low velocity in a high-temperature environment. In addition, its size and shape should be compatible to the tin to be convenient to move along the oven during baking. This paper describes the development of a travelling anemometer to measure absolute velocity in industrial baking ovens, based on the principal that the temperature of a heated wire drops proportionally to airflow velocity. The sensor has two major components: probe and energy supply. Various types of wires and different capacities were studied to design a sensitive probe. The developed sensor was then calibrated against a commercial anemometer. A mathematical model was established to describe the relationship between temperature drop and velocity. It produced a residual of 0.0748 and a correlation coefficient of 0.9893 between the modelled values and the measured values. Finally the developed anemometer was tested in an industrial bread-baking oven to assess its potential for industrial applications.