(512) May 2008 Thermal Management Thrust Area Overview Dr. Thomas M. Kiehne Department of Mechanical Engineering & Applied Research Laboratories The University of Texas at Austin

My Purpose Today Explain this research thrust to consortium members –What is system-level thermal management? –Why is it important? –What is our approach to this research? –What research has gone before? –What is the future research focus? –What deliverables are important to the Navy? Discuss a vision of how we can get this research done VG 12968m

Advanced Naval Power Systems Integrated Power System Integrated Thermal & Power Management Systems Electromagnetic VLS Quiet Motor Drive Advanced Motor & Propulsor High Energy Laser Energy Storage Actuators and Auxiliaries Pulse Forming Network Pulse Forming Network Advanced Generators Electric Warship Major System Components Distribution Fuel Cell Sensors High Power Microwave Electromagnetic Gun ENERGY STORAGE Capacitors Batteries POWER CONTROL AND DISTRIBUTION Switching & Conditioning Power Transmission & Distribution Thermal Management Electrical Architecture POWER GENERATION Prime Movers Generators Fuel Cells & Fuel Reforming Advanced Electric Power Systems Energy Storage Components Motors and Actuators Dr. Richard T. Carlin, Department Head, Sea Warfare and Weapons (Code 33) (Sep 2007) These are thermal machines. These all have thermal impact – Some huge!

Ship Services Power GenerationPower Conditioning & DistributionPower Conversion Power Consumption Prime MoversGenerators Synchro./Sep. Exc. Synchro./PM Super-conductive Homo/hetero Polar Diesel Engine Gas Turbine Nuclear Power Plant Fuel Cells G2 G3 G4 G1 Fuel Optional Energy Storage Gear Synchro./Sep. Exc. Synchro./PM Super-conductive Homo/hetero Polar Variable Reluctance M2 M4 M3 M5 M6 M1 Induction Motors Direct Drive Propeller Podded PropulsionNon-podded Propulsion Motor + propeller in single unit Motor on board Transformers Converters Propulsion Ship Services PWM Synchro Cyclo Rectifier AC or DC Transmission? Loads Pulse Loads VG 12968b Power System Option Summary Everything generates a thermal load: component and system-level thermal challenges are everywhere.

All-Electric Ship TM Challenges 1) Conventional cooling techniques and technologies are likely not adequate for the future all-electric ship. 2) Energy recovery and reutilization are highly desirable. 3) Efficiency and cost have become “drivers”. Conservative estimate of 600% increase in required cooling capacity! DDG-1000 is already here… without a railgun!

Integrated Propulsion System Estimated Cooling Loads/ Waste Heat Distribution 136 MW 11 MW energy thrown away

Need for Thermal Management at the System-Level All of the following have thermal losses with efficiency impacts; some are huge –prime movers –motors –generators –power electronics –storage systems –weapons systems –sensors –etc. Advances in thermal management can –reduce the cost of removing heat –identify opportunities to reuse heat thus improving efficiency and reducing signature –provide for reconfigurable TM and control VG 12968m

The ESRDC is Tasked to Support Key Design and Manufacturing Challenges Challenge Design of first-of-a-kind ship Manufacturing of first-of-a-kind ship Reduction of cost in limited production run Incorporation of emerging technology throughout the process Technical Tools High fidelity modeling “Blue collar” supercomputing Accounting for uncertainty Reduced fidelity modeling for trades Coupled multi-physics Multi-scale Model as specification Model validation on subsystems Component optimization Design modifications Properties in model and use environment Subsystem testing using emerging technologies Clearly, system-level thermal management is one of the key design challenges. Increasing model utility

All-Electric Ship TM Challenges Thermal management is an enabler for the AES Advanced TM techniques and technologies will likely be necessary Distributed, mega-Watt heat loads will be present propulsion motors & converters radar & sonar systems pulsed weapons (lasers, rail guns, etc.) An integrated approach is needed to assess and predict: technology impact interactions/synergies opportunities for increased efficiency [6]

TM Research Approach in the ESRDC Large system thermal modeling and simulation With models that: –represent components and devices at the subsystem level –include components and subsystems that interact with one another in a physically realistic way –are dynamic in nature –are soundly based on fundamental physics and traditional engineering practice –are capable of being implemented on multiple platforms (VTB, ProTRAX, MatLab/Simulink, RTDS, etc.) and in various high-level languages (Fortran, C, C++, Java, etc.) –Are transferable to the Navy and its contractors; which implies interaction with the Navy and its contractors

An electronic handout (“System-Level Thermal Management Research Program”) is available and addresses these topics: –Vision –Research Objectives and Focus –Research Justification –Research Goals –Prior Accomplishments –Related Publications Ask and you shall receive If you want a better understanding of past ESDRC TM Activity

Selected Past TM Activity at UT 1) Representation of thermal management systems for DDG-51, Flight 2A of the Arleigh-Burke class destroyer [“Simulation of DDG 51 Thermal Management Systems”, Symp. on Systems for Electric Ships, American Society of Naval Engineers, Annapolis, MD, Dec 2004] 2) Modeling and simulation of railgun, pulsed weapon system [“System-Level Thermal Management of Pulsed Loads on an All-Electric Ship”, T. Webb, T. Kiehne, IEEE Transactions on Magnetics, January 2007, Volume 43 Number 1, pp and in student thesis] 3) Dynamic simulation of the York 200 ton chiller [Documented in thesis and various reports; paper to be published; additional work to be reported in this presentation] 4) Simulation of thermal-mechanical-electrical aspects of IPS like that on the DDG 1000 [Recently documented in IEEE paper “Estimation of System-Level Thermal Loads on DDG 1000” and thesis “Dynamic Thermal-Mechanical-Electrical Modeling of the Integrated Propulsion System of a Notional All-Electric Ship; Summary contained in ASNE Day paper: “Thermal Aspects of the DDG 1000”]

Selected Past TM Activity at USC 1)Development and Update of Thermo-fluid Component Models in VTB a)Pipe models with pressure drops b)Compressor, pump, valve, various kinds of heat exchangers, etc. c)PEM (Proton Exchange Membrane) fuel cell thermal model d)SOFC (Solid Oxide Fuel Cell) fuel cell thermal model) 2)System Configuration and Performance Studies Of Solid Oxide Fuel Cell-Gas Turbine Hybrid Cycle a)Developed and validated a hybrid SOFC-Gas Turbine Power Cycle in VTB b)Performance of the system with and without cogeneration and effect of various operating parameters were studied 3)Development of Hybrid Ship System Propulsion Power Generation a)Studied the feasibility of such a power generation system b)Overall efficiency evaluated as a function of operating parameters 4)Real Time Thermal Models in VTB a)Hardware-in-the-loop studies b)Interface of Real Time Thermal Models with FSU’s RTDS 5)Thermal Modeling and Simulation for All Electric Ship System in VTB

Selected Past TM Activity at FSU 1) Co-Simulation of Electro-Thermal System Interactions on Future All-Electric Ships [A Co-Simulation Approach for Real-Time Transient Analysis of Electro-Thermal System Interactions on Board of Future All Electric 2007 Summer Computer Simulation Conference (SCSC'07), San Diego, CA] 2) Coupled Thermal-Electrical-Mechanical, System-Level, Simulations [“Modeling and Simulation of the Thermal and Psychrometric Transient Response of All Electric Ships, Internal Compartments and 2007 Summer Computer Simulation Conference (SCSC'07), San Diego, CA] 3) Hybrid fuel cell based systems and their integration into the all- electrical power system [“Constructal Flow Structure for a Single International Journal of Energy Research, 2007, In press]

Let’s look to the future.

Thermal Management Vision Deliver to the Navy the validated capability to conduct thermal-mechanical-electrical system- level simulations at the component level. Use these simulations to address integrated thermal efficiency, performance, and effectiveness of the Navy’s future all-electric ships. Provide a resource for the Navy to catalog and investigate system-level options for thermal management and control of future all-electric ship systems.

Waste heat capture and reutilization: Where heat is present, regardless of its quality, investigate and define technologies to reduce it, remove it, and/or convert it to useful purposes. Reconfigurability and design redundancy: Configure ship system thermal management at the architectural level to handle day-to-day loads very efficiently while rapidly and responsively reconfiguring for combat-related loads. Everything that we do must be useful to, and generate S&T deliverables for, the Navy. Future Research Vision

Expected Deliverables Physics-based, system-level modeling and simulation tools that permit rapid turn around analysis of technology options and design tradeoffs for thermal management. Development, validation, and demonstration of techniques for intelligent, reconfigurable thermal load management. Validated techniques for thermal energy efficiency, energy recovery, and reutilization as they impact cost and effectiveness. Consideration of advanced chiller and heat exchange techniques that focus on thermal energy efficiency and energy reutilization. New energy management methods and techniques adapted to the all-electric warship environment. If what we are doing cannot be clearly assigned against one of these deliverables, we should not be doing it!

How do we build on prior TM work as we execute the current ONR contract? A series of significant system demonstrations, extending over a number of years, are evolving in the Navy. We expect to hear more about this tomorrow and on Thursday.

Medium Voltage DC (MVDC) Power Demonstration Clearly much more detail is needed; but this is a beginning.

The MVDC demo has the potential to be just the ship system-level electrical construct that we have sought. There is a potential for real data being available during this demonstration. We believe that the consortium is well positioned to overlay a thermal management construct on this or any similar architecture.

Major Issues (according to Terry Ericsen) No tool consistency -- venders, shipbuilders, Navy IP prevents model reuse and VV&A No system-level design tools No physics in high-level simulations

I welcome your Questions?