Power Technologies Pervasive & Enabling

Transcription

1 Thermal Management Challenges of Military Electronics Mark S. Spector, Ph.D. Office of Naval Research Ships and Engineering Systems Division, Code 331 Phone: NSF Transport Phenomena Research & Education Workshop 17 May 2007

2 Power Technologies Pervasive & Enabling TAXONOMY POWER GENERATION Fuel Cells & Fuel Reforming Novel Power ENERGY STORAGE Batteries Capacitors Electric Warship FUEL CELL More Electric Aircraft Auxiliary and Primary Power Needs Space Based Radar POWER CONTROL AND DISTRIBUTION FY02 FY12 Switching & Conditioning Power Transmission & Distribution Thermal Management High Power Microwave Hybrid/Electric Combat Vehicle Warrior

3 DoD vs Commercial Requirements 1G Power, Watts 10 M X Future Combat System, Mobility X Home X Cars 100K 1K DoD Focus X Ship DDX (Destroyer) X Directed Energy Weapons X Satellites X Warrior X Tools X Laptops X Cell Phones X Cameras Commercial Focus X Watches Sec Min Hrs Days Month Years Mission Length

4 DoD Thermal Management Issues Current and future DOD weapon systems lack the necessary cooling to provide optimum system level capability. Existing cooling capacity, for the most part, is fully utilized leaving little flexibility for additional cooling requirements. Requirements of future high power DOD systems will require the timely development of efficient and robust thermal management technologies and architectures.

5 Future Electric Warships Heat loads for electric Navy are increasing and need to be dissipated. Future Warships will have electrically powered: Propulsion Systems High Power Weapons Sensors Auxiliary Systems, Launchers, Countermeasures

6 Total A/C Req'd (Tons) New Surface Combatant Thermal Cooling Requirements 7000 Limit of cooling on DDX-sized platform using today s technology DDX 0 Today's Destroyer Power Electronics Advanced Radar Kinetic Energy Weapons HVAC system is the largest integrated system on the ship! Directed Energy Weapons DDG91 5@200 Tons DDX 5@500 Tons CGX? (3000 Tons) CVN68 10@363 Tons CVN76 5@800 Tons CVN78 11@870 Tons At 97 F Seawater

7 DoD Thermal Management Needs Research Drivers Existing cooling systems being fully utilized Increasing component heat fluxes, total power across all platforms Increased operation in warm climates COTS electronics in military environment Heat, cold, moisture, dust Modifications eg. conduction cooling of air-cooled boards Technology Gaps Liquid-vapor transport large systems, vapor separation Fluids and Materials Physics-based models of two-phase heat transfer Thermal storage for pulse power applications Waste heat conversion System level attributes Reliability, Survivability, Maintainability Modeling and Simulation tools

8 DoD Thermal Management Efforts Objectives: Provide enabling technologies for future high power direct energy applications and advanced power conditioning components. Current Efforts: Laser and HPM cooling technologies Continuous large area cooling Integral power electronics and conditioning Compact cooling capacity (~ 1kW/cm2) 10kw thermal bus demonstration for space Continuous high power two-phase cooling Demonstrate burst mode cooling operation Technical Issues: Optimization for Thermal Management Uniform large area cooling at high heat fluxes Working fluid limits Vapor separation, micro-g issues for twophase High power transport & heat rejection issues New Thermal Management for High Power Capabilities

9 Thermal Management Approaches Single Phase Cooling Concepts To date: most common, low risk approach Subcooled nucleate boiling (mimic single phase from a system perspective) Micro channels Confined jets Two Phase Passive Cooling Concepts Everyone wants this approach.although there are realistic limitations to heat flux and transport capabilities Loop heat pipes Capillary pumped loops Bypass valve Reservoir Electric valve Liquid line Two Phase Active Cooling Concepts Pump Spray chamber P2 Heater plate Higher risk.inherent issues with integration limited demonstration in realistic Flowmeter 0.1 to 1.0 gpm environments Sprays Vapor driven nozzles Subcooled sprays Saturated sprays Two phase jets Flow boiling Preheater Filter P1 From cold bath Tl Condenser To cold bath 3 4 Nozzle plate Two-phase fluid line g incident radiation Thermocouples Hot surface

10 Power Electronics, HPM, HEL Diode/Slab Thermal Management Single Phase Cooling Concepts 2007 (TRL 5-6+) Operating Temp: C, C Thermal Transport: <50kW Heat Flux: W/cm 2 Flow Rate: 30-50gal/min Subcooled nucleate boiling High press. inlet at low temp. Reduce system mass and volume Reduce high flow rates and pressure drops Reduce pumping penalties Working fluid limits (temp. and critical heat flux) Current Technology Advances (as of FY06) Subcooled nucleate boiling (TRL 4-5): Operating Temp: C Thermal Transport: 22kW Heat Flux: 900W/cm 2 Flow Rate: 4.8gal/min (60psia) No change CPI integrating subcooled nucleate boiling into gyrotron goal: 2.5MW 2009 (TRL 3-4) Operating Temp: C, C, C Thermal Transport: kW Heat Flux: W/cm (TRL 5-6) Operating Temp: C, C, C Thermal Transport: kW Heat Flux: W/cm 2 Component testing: scaling for high flux and high thermal power transport Subscale integration: testing of acquisition, transport, and rejection technologies, e.g.: 50, 100, 500kW demos Flight testing Failure mode analysis, reliability,.

11 Power Electronics, HPM, HEL Diode/Slab Thermal Management Two Phase Passive Cooling Concepts Pump assisted Capillary Pumped Loop (CPL) Loop heat pipe Integral nano- and micro-scale concepts 2007 (TRL 2-3) Operating Temp: C, C Thermal Transport: 1kW Heat Flux: 100W/cm 2 Current Technology Advances (as of FY06) Pump assisted CPL (TRL 3-4): Operating Temp: C Thermal Transport: 1.3kW Heat Flux: 10-30W/cm 2 High temp loop heat pipe (TRL 3-4) Operating Temp: C Thermal Transport: 500W Heat Flux: 3-30W/cm (TRL 3-4) Operating Temp: C, C, C Thermal Transport: 5kW Heat Flux: 100W/cm (TRL 5-6) Operating Temp: C, C, C Thermal Transport: 10kW Heat Flux: 100W/cm 2 Component testing: scaling for high flux and high thermal power transport Subscale integration: testing of acquisition, transport, and rejection technologies, e.g.: 1, 5, 10kW demos Flight testing Failure mode analysis, reliability,.

12 Power Electronics, HPM, HEL Diode/Slab Thermal Management Two Phase Active Cooling Concepts Jet impingement, spray cooling concepts Heat pump, refrigeration; pumped loop concepts Liquid vapor separators tolerant of micro-g to high-g transients Thermal architecture/system level studies Nano-fluid/working fluid development Energy harvesting technologies High rate thermal energy storage Integral and scalable micro-thermal concepts 2007 (TRL 3-4) Operating Temp: C, C Thermal Transport: kW Heat Flux: W/cm 2 Current Technology Advances (as of FY06) Two-Phase Spray Cooling(TRL 3-4): Operating Temp: 20 0 C, C Thermal Transport: 20kW, 10.5kW Heat Flux: 500W/cm 2, 500W/cm 2 Variable-g flight testing 50+ hours of variable-g operation of a twophase, single nozzle spray with L-V separation 2009 (TRL 3-4) Operating Temp: C, C Thermal Transport: kW Heat Flux: W/cm (TRL 5-6) Operating Temp: C, C Thermal Transport: kW Heat Flux: W/cm 2 Component testing: scaling for high flux and high thermal power transport Subscale integration: testing of acquisition, transport, and rejection technologies, e.g.: 10, 500, 1000kW demos Flight testing Failure mode analysis, reliability,.

13 System Level Issues A Total Systems approach to Thermal Management is needed to enable the Future Navy Bundling and Smart Integration into current and future fleet. Development of a Ship Level Thermal Management Model for rapid, virtual concept development and testing. Improved Large capacity AC plants that are compact, efficient, quiet, and low maintenance for Next Navy. New technologies for enabling Advanced Electronics, Power Generation Modules, Energy Storage and Pulsed Power Technologies. New Architectural Designs for seamless integration of TM.