plummer_meen1210- Nitrogen Powered Vehicles

plummer_meen1210- Nitrogen Powered Vehicles - Feasibility...

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Unformatted text preview: Feasibility of Liquid Nitrogen Powered Vehicles M.C. Plummer, C.A. Ordonez, R.F. Reidy University of North Texas, Denton, Texas y Acknowledgements Students-- Michael Ham, Daniel Graber, Rick Bassham Sponsors-Sponsors-- Thermax, MVE, IngersollIngersollRand, Rand CBS Mechanical Finned Tube Mechanical, Tube, TriTec Power Systems,Texas Advanced Research Program and UNT Program, UNT CooLN2Car Project OUTLINE Rationale for zero/low emission vehicles Concepts of liquid nitrogen power Low emission technologies Development of C LN2C D l t f CooLN2Car Analysis of cryogenic heat engine designs Impact of emerging technologies p g g g UNT CooLN2Car Project Future possibilities Rationale for zero emission vehicles Increased greenhouse gas concentrations could dramatically effect y world climates Finite petroleum resources Local effects of emissions (ozone, NOx) Dictated by California d New Y k Di t t d b C lif i and N York legislatures UNT CooLN2Car Project Carbon Dioxide Production and Warming Trend Hadley Centre for Climate Change and Research UNT CooLN2Car Project Influences to Carbon Cycle y UNT CooLN2Car Project Zero/Low Emission Vehicles Systems Hybrid (gasoline/diesel + battery) Electric Battery (metal hydride) Fuel Cell Compressed G C d Gas Liquid Nitrogen/Air UNT CooLN2Car Project GasGas-Electric Hybrid Production models: Toyota Prius (47 mpg), ( pg) Honda VV (50+ mpg) good performance inexpensive ($17 500 in Japan) ($17,500 not zero emission UNT CooLN2Car Project Electric Battery Vehicles Production: GM EV-1 EVzero emission metal hydride batteries limited li it d range recharging issues battery lifetime expensive ($30k+) specific energy UNT CooLN2Car Project Fuel Cell Cars Production: buses, GM Zafira, Zevco high efficiency (35-50%) (35require platinum startup (h t up catalyst) t t (heat t l t) hydrogen or methanol fuel over $1 billion spent on fuel cell research UNT CooLN2Car Project Compressed Gas Vehicles Efforts in Europe pressures to 33 MPa claimed range to 120 miles 40,000 claimed sales to Mexico City of 40 000 taxis fillup less than 3 minutes claimed efficiencies of 85% Cheap ($13,000) in year 2,000 No cryogenics involved UNT CooLN2Car Project Specific Energy Values System Spec. Energy 4 MPa (580 p ) adiabatic ( psi) 195 + 300 4 MPa (580 psi) isothermal 315 + 300 lead/acid batteries 190 midmid-term battery goal 290 gasoline (HHV) 48,350 UNT CooLN2Car Project Cryogenic Heat Engines a cryogenic substance is used as a heat g sink for a heat engine liquid nitrogen (LN2) is vaporized, then expanded through an expansion engine to produce work. C. A. Ordonez, "Cryogenic Heat Engine," American Journal of Physics Vol. 64, 479-481 (1996). 479- UNT CooLN2Car Project Conventional Heat Engine Combustion (heat source) Engine Atmospheric air ( (heat sink) ) Work UNT CooLN2Car Project Cryogenic Heat Engine Atmospheric air (heat source) Engine Liquid nitrogen ( (heat sink) ) Work UNT CooLN2Car Project Different Gas Expansion Engines Simple open cycle Reheated open cycle Brayton cycle Rankine R ki cycle l UNT CooLN2Car Project Comparison of Several Engine Cycles Researcher Plummer Plummer u e Plummer Ordonez Knowlen Knowlen Cycle single reheat doub e e eat double reheat triple reheat Brayton Binary Rankine Ternary Rankine Energy (kJ/kg ( / g of LN2) ) 225 250 50 256 400 200-380 200300300-480 UNT CooLN2Car Project Results for Different Reheat Cycles Reheats Reheat condition adiabatic const press const vol const press const vol const press const vol isothermal Expansion Exhaust Total ratio pressure work (kPa) (kJ/kg) 22.0 22 0 150 180 3.1 140 225 3.6 36 150 243 2.2 120 250 2.5 25 144 284 1.8 124 256 2.1 145 316 22.0 150 UNT CooLN2Car Project 291 0 1 1 2 2 3 3 Closed Brayton Cycle Processes 1 Gas cooled to LN2 Temps 2 Gas compressed to Op. p p Pressure 3 Gas heated by exhaust 4 Gas heated by atmosphere 5 Gas expanded to do work 6 Exhaust gas heats pressurized gas UNT CooLN2Car Project Schematic of CooLN2Car UNT CooLN2Car Project Advantages of Liquid-Nitrogen LiquidSystems over Chemical S t Ch i l Batteries vehicle cost hi l t safety no CFC's for air conditioning rapid refueling reduction of airborne particulates higher specific energy UNT CooLN2Car Project Potential Fuel Costs for Liquid Nitrogen Powered Vehicles Source Solar based energy Off-peak nuclear Current C t Gasoline Costs/mile 10 2.4 5 UNT CooLN2Car Project Status of C S f Current V hi l Vehicle current max speed: 36 mph (58 kph) current range: 16 miles (26 km) fuel economy: .3 to .5 mpg Design Parameter for Next Vehicle (The Truck) Range : 100 miles (161 km) Top Speed: 65 mph (105 kph) Reheat Stages: 1 Fuel Economy: >1.0 mpg F lE 10 Operating Pressure: 500 psi (3.45 Mpa) Fuel Tanks: 2 at 50 gallons each Platform: Custom UNT CooLN2Car Project Near Term Areas of Research High Pressure Motors Throttles Frost Free Heat Exchangers Reduction f R lli R i t R d ti of Rolling Resistance Assembly of High Pressure Systems UNT CooLN2Car Project Longer Term Areas of Research 1,000 to 5,000 psi systems Incorporation of thermoelectrics Vehicle integration Aerodynamics / heat exchanger A d i h t h tradeoffs Weight reduction High efficiency cycles g y y UNT CooLN2Car Project Conclusions LN2 vehicles can have superior performance potential when compared to battery powered vehicles. The cost of oil will have to increase substantially to make any ZEV economically b i ll k i ll viable. Concern over green house emissions might C h i i i ht force the development independent of economic considerations considerations. UNT CooLN2Car Project Schematic of Future Car Design g UNT CooLN2Car Project Applicable Emerging Technologies solar dish engines thermoelectrics pulse tube refrigerators regenerative braking ti b ki novel materials UNT CooLN2Car Project Solar Dish Engines mirror array focus solar rays onto receiver --> electricity 30% conversion efficiencies up to 25 kW electricity source Stirling engine direct liquefaction of nitrogen UNT CooLN2Car Project Thermoelectrics Placed around boiler near tank large temperature difference between ambient and cryogenic liquid produces source of electrical power precludes the need for battery storage UNT CooLN2Car Project Pulse Tube Refrigeration efficient means of gas liquefaction g q scalable to large production volumes NISTNIST-Boulder currently developing remote natural gas liquefaction system could be powered by solar dish engines ld b db l di h i UNT CooLN2Car Project Regenerative Braking means of capturing kinetic energy of braking 1-2 kW available in city driving y g heat from brakes --> heat exchangers --> UNT CooLN2Car Project Novel Materials lightweight polymers for body parts lightweight tanks advanced insulator materials-- aerogels materials-- UNT CooLN2Car Project Brayton Cycle UNT CooLN2Car Project Changes in Carbon Emission UNT CooLN2Car Project Antarctic CO2 and Local Temperatures UNT CooLN2Car Project Rankine Cycle Work by Knowlen UNT CooLN2Car Project ...
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This note was uploaded on 05/14/2008 for the course MEEN 1210 taught by Professor Traum during the Winter '07 term at North Texas.

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