Previously Reported Bubble Points

LH Paynter 1973b Burge Blackmon 1973 Cady 1973 Cady 1975 Cady 1977 k Chato and Kudlac 2002 A Kudlacand Jurns 2006 O Jurns et al. 2007 — Curve Fit 

FIGURE 3.8 Historical Bubble Point Data for (a) 200 x 1400 and (b) 325 x 2300 Mesh Screens. 

FIGURE 3.9 Average Pore Diameter as a Function of the Fineness of the Mesh. 

Note that this assumes perfect linearity between bubble point pressure and surface tension, all the way down to cryogenic temperatures. 

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Appendix A presents a historical summary of previously attempted depot demonstration missions. Appendix B presents the full list of screens available for screen channel IADs as well as a summary of the data mining of all previously reported bubble point data. Appendices C and D present Langmuir isotherms for the data presented in Chapter 4 while Appendix E presents previously reported heated pressurant gas historical data relevant to Chapter 8. Appendix F presents the results of the literature review into previous solutions for porous channel flow. Appendix G presents LAD design logic and a summary of updated design tools. 

Rigorous and comprehensive survey of the literature was performed to gather all previously reported bubble point data for all possible screens. Detailed results are reserved for Chapter 10, where the full cryogenic bubble point pressure model is constructed. Appendbc B lists the 40 screens over which information is available in the literature. 24 of these 40 screens have actual historical bubble point data available pore diameter data for two new screens are added for the current work for a total of 26 screens. Figures 3.8a... 

Summary of Previously Reported Bubble Point Data... 

Ln addition, examination of Equation (3.16) shows that the current bubble point model does not account for variations in pressurant gas temperature, so warm gas data will be valuable for improving the prediction for cryogenic systems. Previous attempts were made to quantify the effect of warm gas on LAD degradation in the literature, but there were numerous reported inconsistencies in results as well as issues reported with the test apparatus. Historical attempts to quantify this effect are reserved for Appendix E. Clearly, carefully designed and controlled tests are required to accurately quantify the effect of warm pressurant gas on LAD performance. 

To rule out the possibility that the lower 510 x 3600 bubble point pressures reported in Chapter 4 were not caused by defects, repeat bubble point tests were conducted in IPA. No deviation was noticed from previously reported values. Additional 510 x 3600 screen samples were tested from different batches of raw materials, and still there was no deviation... 

As mentioned in Section 3.9.2, there are only three previous studies where reseal data was reported. Reseal pressure data was collected alongside all bubble point test data from both room temperature as well as cryogenic bubble point tests for a 200 x 1400, 325 x 2300, 450x2750, and 510x3600 Dutch Twill LAD screen in IPA, methanol, acetone, water, LH2, LN2, LQX, and LCH4. A total of 4836 reseal pressure data points, of which 4815 were new points, were collected, processed, and analyzed to develop this model. 

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