Gradient heat flux measurement in study of unsteady water film boiling at the surface of the sphere

Abstract

Abstract The new method of study heat transfer is the gradient heat flux measurement. It allows measuring the heat flux per unit area for unsteady film boiling at the spherical surface. For the first time distribution over the surface of heat flux per unit area and heat transfer coefficient were derived. The time dependences for the local heat flux per unit area and heat transfer coefficient were obtained in different angles of the spherical surface. The spherical surface was made of titanium VT 22 with a diameter of 20 mm. High-speed shooting supplemented the experimental curves with a frequency of 1 kHz. The error of heat flux per unit area measurement was not exceeding 12%.