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[strider]

Hi,

I am doing a project in my undergraduate studies in two-phase flow and it requires me to calculate the quality (vapour/total) at various heights in a cylindrical glass tube.

The setup is a vertical cylindrical glass tube of around 10 cm diameter and is supplied by saturated water at 100 degrees Celsius from the bottom by means of a pump. The saturated water, as it flows up thru the cylindrical tube, is heated by four strip heaters placed vertically along the length of the tube and hence bubbles appear as it moves up. The flow is made homogeneous by means of a circular distributor placed halfway along the height of the cylinder. I captured high speed images of the flow at three heights (80 images per second) and from these images i am supposed to calculate the quality of the flow at that specific height.

Using Image Pro Plus, i can convert the black and white image i obtain to just a 2 color image where BLACK = vapour and WHITE = liquid roughly. And then i can get the ratio of the vapour to liquid for the 2-dimensional projection of the cylindrical tube.

The question is now, how to calculate the quality from this ratio.
Since quality is the mass to mass ratio of the vapour to total mass, i can calculate it once i get the volume vapour / total volume at a particular height.

This is a sample of the image i obtain using the camera:



(The central black rod is the thermocouple)

Also please suggest any other way to measure the quality of the vapour at a certain height. That is, infact, my prime objective.

Thnx

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