Physics & Astronomy ETDs


Pyung Syk Ro

Publication Date



The basic equation (Maxwell equation) for the evaporation rate of small droplets motionless relative to the ambient gas is verified by our experiment using an ultrasonic droplet suspension device. By using an ultrasonic device, a good approximation to the conditions of evaporation of free water droplets ranging from 0.4 mm to 2.0 mm in diameter is obtained.

Since it is expected that the back-scattering cross section of an incoherent light beam from a water drop is proportional to the square of the radius of the water drop, the possibility of measuring evaporation rates by using incoherent light is suggested. This possibility is borne out by our experiment and shows promise.

The temperature of the droplet near its surface is directly measured using thermistors, and our measurement agrees well with the theory. Evaporation rates using the thermistor to support the droplet are measured also.

Theoretical calculations of evaporation rates are discussed, and values predicted by these calculations are compared with our experimental results.

The evaporation rates obtained using the ultrasonic suspension method agree well with the theoretical calculations, whereas the rates obtained using the thermistor foe support do not agree well.

Degree Name


Level of Degree


Department Name

Physics & Astronomy

First Committee Member (Chair)

Howard Carnes Bryant

Second Committee Member

John Lee Howarth

Third Committee Member

Victor H. Regener



Document Type