Mechanical Engineering, Isfahan University of Technology
Mechanical Engineering, Southern Illinois University
An experimental investigation was carried out to determine heat transfer coefficients for natural convection from a heated horizontal wire. The heating is provided by electrical current, and the temperature of the wire is determined from the measurement of its resistance. The experiments are performed in three different convective environments: air, water, and oil. Prandtl number ranged between 0.702 and 5864, while the Grashof number and Rayleigh number varied respectively from 2.6×10-6 to 8.7 and 0.015 to 26. The Nusselt number results are correlated as a function of Rayleigh number, without dependence on Prandtl number.