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This work reviews the major published studies, both theoretical and experimental, that address the impact of wave motion on packed tower performance. Current practice is to add excess packing to guarantee the required separation is obtained, though there is little data available to derive a safety factor for packing height. This work highlights deficiencies in the current knowledge base and analyzes general trends to address common misconceptions about tower design for floating production. Tilt and motions imposed on a fractionation column have a significant impact on product specifications due to reduced packing efficiency. Improved awareness of motion impacts will assist the analysis of tower design and allow feedback to the process design. Identifying gaps in available data shows limits in the current understanding and allows the development of appropriate simplifying assumptions. The current understanding of towers in motion allows only very basic design rules and the safety factor for packing height in literature varies from 1.1 to 2.0. This provides little confidence in the ability to predict packing efficiency for floating production. Static tilt is more detrimental to liquid distribution than motion at a given amplitude. Still, liquid maldistribution from motion approaches that of static tilt as the period increases. Liquid sloshing, often cited as a significant concern, is a relatively minor contribution to maldistribution except for short periods and tall towers. The relative bed size has a significant impact on liquid maldistribution, limiting the recommended maximum bed height:column diameter to 2 – 3 to maximize the efficiency. Approach to equilibrium is often overlooked as the major determinant of sensitivity of efficiency to maldistribution. Separations that operate near equilibrium are more sensitive to maldistribution than services with a large driving force. Thus, distillation towers are generally more sensitive to motion than absorbers and sensitivity may vary over column height. Recommendations are provided for a bed-by-bed analysis and feedback to the process design. Floating production units require additional complexity and conservatism in tower design. An improved awareness of motion effects on towers, and the factors involved, will lead to improved designs and a reduction in the cost of floating production facilities.

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information, Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY)2. REPORT TYPE 3. DATES COVERED (From -To) PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) PERFORMING ORGANIZATION University of Texas at Arlington REPORT NUMBEROffice of Sponsored Projects PO Box 19145 Arlington, TX 76019 SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S)Office of Naval Research ONR 875 N. Randolph St. One Liberty Center Arlington, VA 22203-1995 NUMBER(S) SPONSOR/MONITOR'S REPORT DISTRIBUTION/AVAILABILITY STATEMENTApproved for Public Release; Distribution is Unlimited. SUPPLEMENTARY NOTES ABSTRACTDuring the period of 7/1/2007 --12/31/2007, we performed the following studies on radar sensor network: 1) Network-enabled Electronic Warfare (NEW) for Collaborative Automatic Target Recognition (CATR); 2) Foliage clutter modeling using narrowband and UWB radars; 3) A propagation Environment Modeling in Foliage using UWB radars; 4) Target detection in foliage using shorttime Fourier transform and UWB radar sensor networks; 5) Some experimental studies on path loss models for wireless sensor networks based on Xbow motes, 6) Theoretical studies on distributed connected dominating set construction in random geometric kDisk graphs for potential application to real sensor networks. SUBJECT TERMSRadar Sensor Network, UWB Radar, Sense through foliage, Automatic Target Recognition, clutter modeling. 1. Network-enabled Electronic Warfare (NEW) for Collaborative Automatic Target Recognition (CATR); 2. Foliage clutter modeling using narrowband and UWB radars; 3. A propagation Environment Modeling in Foliage using UWB radars; 4. Target detection in foliage using short-time Fourier transform and UWB radar sensor networks; 5. Some experimental studies on path loss models for wireless sensor networks based on Xbow motes, 6. Theoretical studies on distributed connected dominating set construction in random geometric k-Disk graphs for potential application to real sensor networks. NEW-CATR: Network-enabled Electronic Warfare for Collaborative Automatic Target RecognitionNetwork-enabled Electronic Warfare (NEW) is to develop modeling and simulation eff...

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