logging in or signing up Schmidt Columbia Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 341 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: November 08, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript A Model for Purging a 15,000 ton LAR TPC tank : A Model for Purging a 15,000 ton LAR TPC tank Richard Schmitt Fermi National Accelerator Lab March 13, 2006Topics: Topics Large flat bottom tanks Purging goal Calculation results Examples PlansFlat Bottom Tank: Flat Bottom Tank Commonly used for largest LNG (liquefied natural gas) storage Well known technology Excellent safety record Reasonable cost Can not withstand vacuum Slide5: 50 m diameterAir Purging Goals: Air Purging Goals Purge to less than 10 ppm O2 Liquid Argon arrives with 1 ppm oxygen and is purified Warm gas contain 0.1% of the contamination that must be removed Purge in a reasonable length of time Analysis & Calculations: Analysis & Calculations ANSYS-CFX, finite volume analysis Hand calculations Fick’s law Boundary layer Perfect mixing Uniform Inlet, Single Outlet: Uniform Inlet, Single Outlet Tank Diameter 24.5 m Tank Height 24.5 m Total flow 8.5 m3/minute Tank volume change every 22 hours Isothermal at 20CSlide9: One volume changeSlide10: Concentration after nine volume changes Center of tank is in upper left Single Outlet Conclusions: Single Outlet Conclusions Residual air is left in the outer, upper part of the tank Average oxygen concentration is 300 ppm A single outlet is inadequateLocal inlet model: Local inlet model Inlet spacing 2.1 m 100 inlets Model height 2.4 mSlide13: One ppm reached in 30 hours at 2.4 m elevation Some mixing occurs Distribution plotSlide14: Red 3200 to 3600 ppm oxygen Orange 2800 to 3200 ppm oxygenHand Calculations: Hand Calculations As a rough check of ANSYS analysis Diffusion calculations per Fick’s Law Boundary layer diffusion Perfect mixing Purging Examples: Purging Examples LNG tank purging SELEX Ring Imaging Cherenkov Small test tank LNG tank purging: LNG tank purging One inlet/one outlet Purged with nitrogen at room temperature Typically achieve 1% oxygen in one day, one volume change This rough number compares well with the single outlet model Initially outlet is all air later oxygen concentration drops rapidlySELEX RICH: SELEX RICH Purged with Neon 44 m3 volume, horizontal cylinder Purge headers along the top and bottom Purge rate 0.5 m3/minute Outlet reached 2 ppm oxygen in 7 hoursSmall tank: Small tank Vertical, cylindrical tank 1.5m diameter, 4.5m3 volume Mean velocity 1.2m/hour Dispersed inlet, single outletSmall tank model early results: Small tank model early results 0.3 hours One hourSlide21: one volume changeSmall Tank - outlet: Small Tank - outlet Supply argon contains 8.5 ppm oxygen Ten volume changesPlanning: Planning Analyze more details with ANSYS Importance of other contaminants, nitrogen, water, carbon dioxide Test 10 m diameter water tank with distribution and venting pipe system Palladium catalyst vs. venting cost comparison You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Schmidt Columbia Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 341 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: November 08, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript A Model for Purging a 15,000 ton LAR TPC tank : A Model for Purging a 15,000 ton LAR TPC tank Richard Schmitt Fermi National Accelerator Lab March 13, 2006Topics: Topics Large flat bottom tanks Purging goal Calculation results Examples PlansFlat Bottom Tank: Flat Bottom Tank Commonly used for largest LNG (liquefied natural gas) storage Well known technology Excellent safety record Reasonable cost Can not withstand vacuum Slide5: 50 m diameterAir Purging Goals: Air Purging Goals Purge to less than 10 ppm O2 Liquid Argon arrives with 1 ppm oxygen and is purified Warm gas contain 0.1% of the contamination that must be removed Purge in a reasonable length of time Analysis & Calculations: Analysis & Calculations ANSYS-CFX, finite volume analysis Hand calculations Fick’s law Boundary layer Perfect mixing Uniform Inlet, Single Outlet: Uniform Inlet, Single Outlet Tank Diameter 24.5 m Tank Height 24.5 m Total flow 8.5 m3/minute Tank volume change every 22 hours Isothermal at 20CSlide9: One volume changeSlide10: Concentration after nine volume changes Center of tank is in upper left Single Outlet Conclusions: Single Outlet Conclusions Residual air is left in the outer, upper part of the tank Average oxygen concentration is 300 ppm A single outlet is inadequateLocal inlet model: Local inlet model Inlet spacing 2.1 m 100 inlets Model height 2.4 mSlide13: One ppm reached in 30 hours at 2.4 m elevation Some mixing occurs Distribution plotSlide14: Red 3200 to 3600 ppm oxygen Orange 2800 to 3200 ppm oxygenHand Calculations: Hand Calculations As a rough check of ANSYS analysis Diffusion calculations per Fick’s Law Boundary layer diffusion Perfect mixing Purging Examples: Purging Examples LNG tank purging SELEX Ring Imaging Cherenkov Small test tank LNG tank purging: LNG tank purging One inlet/one outlet Purged with nitrogen at room temperature Typically achieve 1% oxygen in one day, one volume change This rough number compares well with the single outlet model Initially outlet is all air later oxygen concentration drops rapidlySELEX RICH: SELEX RICH Purged with Neon 44 m3 volume, horizontal cylinder Purge headers along the top and bottom Purge rate 0.5 m3/minute Outlet reached 2 ppm oxygen in 7 hoursSmall tank: Small tank Vertical, cylindrical tank 1.5m diameter, 4.5m3 volume Mean velocity 1.2m/hour Dispersed inlet, single outletSmall tank model early results: Small tank model early results 0.3 hours One hourSlide21: one volume changeSmall Tank - outlet: Small Tank - outlet Supply argon contains 8.5 ppm oxygen Ten volume changesPlanning: Planning Analyze more details with ANSYS Importance of other contaminants, nitrogen, water, carbon dioxide Test 10 m diameter water tank with distribution and venting pipe system Palladium catalyst vs. venting cost comparison