Analytical screen channel flow model

Analytical Screen Channel Flow Model in Microgravity.345... 

The new analytical model can now be compared to the only two low-error sets of available cryogenic LAD channel flow data. First, horizontal LAD channel data was collected in LOX and presented in Chapter 9. A picture of the LAD channel and dimensions is shown in Figure 12.8. The test setup consisted of a 61 cm long LAD channel with a height of 2.54 cm (1 in.) and a width of 5.08 cm (2 in.). The screen covered 48.2 cm of one side of the... 

To compare performance between vanes and screen channels, expulsion efficiency and resultant PMD mass were determined for both PMDs across a wide range of demand flow rates. Based on the maximum achievable expulsion efficiency and resultant PMD mass, the critical mass flow rate range for the small-scale LH2 tank was determined to be 4 X 10 -1.4 X 10 kg/s, below which vanes are the optimal PMD, above which screen channels are the optimal choice. Finally, comparison of PMD mass shows that, depending on the desire to minimize PMD mass or maximize expulsion efficiency, vanes may be used to supply flow rates as high as 1.4 x 10 kg/s for a small-scale LH2 tank in a continuous outflow. The analysis also showed that there exists a limit on the mass flow rate that a single vane can deliver due to choking. The analytical models and rationale developed here can be used to size and trade PMD performance for any sized propellant tank in any gravitational or thermal environment. 

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