Aerodynamics Research Center ( http://arc.uta.edu) Mechanical and Aerospace Engineering Department (http://www-mae.uta.

1. Phone: 817-272-2603 Fax: 817-272-5010 Prof. Frank K. Lu (franklu@uta.edu) Albert Ortiz (aortiz@uta.edu) Philip Panicker (philipkpanicker@uta.edu) Prof. Don Wilson (wilson@uta.edu) Hybrid Pulsed Detonation Engine (PDE) for Electric Power Generation Based on US Patent Application No. 10/746,863 Hybrid PDEs What is a Pulsed Detonation Engine? How a PDE Works Turbo-Jet Engines vs. PDEs • Pulsed Detonation Engine (PDE) is a revolutionary engine that uses detonation to combust the fuel. • It operates in a cyclical and intermittent fashion. • Detonation is a more rapid and efficient form of combustion, as opposed to deflagration. • PDEs do not need heavy multi-stage compressors. • Thus PDEs can reduce weight, costs and improve fuel efficiency of propulsion systems dramatically. • PDEs can operate from Mach 0 to about 5 and can be used in supersonic or hypersonic vehicles. • PDEs can be applied for ground based or aircraft based electric power generation. • PDE can run on gaseous or liquid fuels, e.g. Hydrogen, Propane (Natural Gas), Coal Gas, Kerosene, Diesel, Jet Fuel, etc. • (The US has vast reserves of Natural Gas and Coal.) • PDE with Hydrogen is the ideal engine of the future. • Turbo-Jet engines (and rockets) use Deflagration to burn its fuel and to generate the energy for thrust. • Turbo-jets follow the Brayton cycle (constant pressure). • PDEs are similar to the Humphrey cycle (constant volume). • Turbo-jets need heavy compressors to compress air before mixing with fuel and burning. • In PDEs the detonation wave does the heavy work. Therefore, no need for compressors. • Otto cycle (internal combustion engines) have maximum efficiency of about 51% (compression ratio 8). • Diesel engine cycle, maximum efficiency is about 65% (compression ratio of 20). Proof of Concept of PDE for Electric Power Generation Experimental Setup Detonation vs. Deflagration Tcycle= Tfilling + Tinitiation + Tdetonation + Texhaust+ Tpurge Tdetonationis very short and quick Tfilling and Tpurgeare the longest stages in the cycle Tpurgeis a necessary and important stage for cooling and cleaning the tube Texhaustis the thrust producing stage • Detonation • Supersonic, 1000s of m/s • Modeled as a constant volume process • Sharp increase in pressure, temperature and density during detonation • Energy release is rapid and efficient Zeldovich-von Neumann-Doring (ZND) model: Shock wave followed closely by a reaction zone Borg-Warner Turbo-charger from a Volkswagen (1800cc) automobile • Deflagration • Subsonic, slow 1-10 m/s, (fastest is a few 100 m/s) • Modeled as a constant pressure process • High temperatures are released, significant loss of pressure and density density during burning • Energy release is slow and inefficient • Propane + Oxygen • Electronically controlled Solenoid Valve Fuel Injection • Automotive Ignition System • Automotive Turbocharger • Compact AC Generator • The PDE was run at 15Hz • The Generator produced 6VRMS at 25W • The Turbine ran at over 127,000 rpm Frequency = 1/Tcycle Shorter Tubes => Higher Frequency Longer Tubes => Lower Frequency Deflagrations can be accelerated to Detonations. But tubes have to be very long to achieve Detonations. The process of going from Deflagration to Detonation is known as Deflagration to Detonation Transition (DDT). Special devices can be used to enhance DDT in a short tube. (One of the focuses of our research). Aerodynamics Research Center(http://arc.uta.edu) Mechanical and Aerospace Engineering Department (http://www-mae.uta.edu) Compact Bicycle AC Generator