2-MODE BOILING ON A HORIZONTAL HEATING WIRE

Two-mode boiling on a horizontal heated wire immersed in a pool of liquid under atmospheric pressure has been investigated. Methanol, acetone, isopropanol and isobutanol were boiled using wires made of tungsten (0.15, 0.50, 0.82, 1.01, and 1.55 mm dia.), tantalum (0.30 and 0.82 mm dia.), molybdenum (0.125 and 1.01 mm dia.), and titanium (1.01 and 1.55 mm dia.). Two-mode boiling may be steady or unsteady. In steady two-mode boiling, both modes of boiling are stationary on the wire. The applied current in this case is referred to as the equilibrium current. In this article a method devised to calculate this current is discussed. The calculated results agreed well with the experimental results. In unsteady two-mode boiling, one of the two modes automatically takes over the other and boiling changes into a one-mode boiling. A method to calculate this transition velocity is presented. The calculated results correlated well with the experimental work.