THE DYNAMIC CHARACTERISTICS OF A LIQUID-GAS INTERFACE IN MICROSCALE PORES
For both Loop Heat Pipes, being developed as a thermal control device for microelectronics in space applications, and the de-watering process in a vibro-separator, the dynamic characteristics of a liquid-gas interface inside micropores greatly affects the efficiency of the entire system. In the pharmaceutical industries, product particles are discharged in the form of a dilute slurry from a reactor to a de-watering device, such as a vibro-separator. For extremely small pores, gravity is insufficient for removing the excess water through the micropore screen. For these cases, it has been suggested that the de-watering process can be initiated by utilizing a vacuum pressure beneath the screen and applying sinusoidal vibration to the screen. To understand the phenomena of de-watering from the product screen of a vibro-separator utilizing vibration and pressure, a single liquid-filled micropore is studied. In past studies , the Navier-Stokes and Young-Laplace equations have been used to describe the dynamic motion of the liquid column and liquid-gas interface. A major goal of this study is to experimentally verify this model. In particular, comparison is made between the amplitude and frequency of acceleration required to cause the bubble burst through predicted theoretically and measured experimentally. The Lexan wicks having several pores with a uniform diameter of 50 ìm, 100 ìm, 500ìm and 1 mm are utilized. Depending upon the size of the micropores, two different types of tests were performed. One test utilized no external pressure difference across the wick and other test utilized a pressurized upper chamber.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:microsale pores loop heat pipes vibro separator mechanical engineering
Date of Publication:01/01/2002