Wright Turbo Compound edit
Overview
An engine that was developed from an idea was made into a proposal and went into production in a short eight years. In those eight years, the Wright Aeronautical Division managed to accumulate a total of 7.5 million flight hours, and more than 25,000 hours of experimented test stand experience. [1]. In all, they managed to design and build an engine that became accepted and proven to be aircraft power plant worthy.
History of Wright Aeronautical Division
On December 17th, 1903 in the dunes of Kitty Hawk, North Carolina, Wilbur and Orville Wright achieved flight in a machine heavier than air. Their machine managed to sustain flight for roughly fifteen seconds. It was this flight that started the age of aviation. Over the next two years, the Wright Brothers perfected their design to sustain flight for over twenty four miles. In 1905, the Wright brothers offered their invention to the United States Army, but their offer was rejected without consideration [2].
In 1909, the first International Aviation Meet was held on Betheny Plain, which is located outside Reims France. The Wright brothers sure of winning, entered three planes into the competition but lost to a young unknown designer and pilot by the name of Glenn Curtiss. As a result to winning the competition in France, Mr. Curtiss expanded his design and research that eventually made world records [3]. In 1916, at the time of World War I, The Curtiss Aeroplane and Motor Company went public to becoming the largest aircraft manufacturing company in the world, and it had Glenn Curtiss as the company President.
With World War I in full swing, it greatly accelerated the pace of airplane development worldwide. In 1919, Wright Aeronautical was incorporated to the Curtiss Aeroplane and Motor Company changing its name to Curtiss-Wright Corporation. Within this new corporation, there were three separate divisions being the Curtiss-Wright Airplane Division, the Curtiss-Wright Propeller Division, and the Wright Aeronautical Division that was responsible for manufacturing and designing aircraft engines. [4].
Development of Turbo Compound
In 1942, the Wright Aeronautical Division started their studies on designing a variety of methods for power recovery in different engines. In the summer of 1946, the Wright Aeronautical Division’s final design was being supported by the Bureau of Aeronautics, United States Navy. The initial motor that was being used for testing was the famous Wright Whirlwind motor. The first full scale compound engine was built with a total of eighteen pistons and a total of six power recovery units or turbo chargers.
Shortly after in 1948, the first orders of turbo compounds were delivered to the United States Navy. A year later, the engine was being used in the nose of a B-17 bomber test flight for the Navy. The engine passed its model test flight and went into mass production in the 1950’s. By 1955, there were approximately 9,000 Turbo Compounds being used, and roughly twenty percent were being used for commercial use [5].
Specs
The Turbo Compound was initially rated at having 3,250 Brake Horsepower Dry, and 3,500 Brake Horsepower Wet. Over time with mechanical advancements, the motors were made more efficient and rated to have 3,400 Brake Horsepower Dry, and 3,700 Brake Horsepower Wet [1]. In regards to the terms "Dry" and "Wet," it refers to how the engine is allowed to produce excess thrust. This process works by injecting water into the later stage of compression lowering the engine combustion temperature. With a lowered combustion temperature, more fuel can be injected into the hot section of the combustion chamber producing a significant amount more of horse power. In an engine sense, the term “compounding” in a compound turbo engine is defined as the engineering process of combining two or more reciprocating units to make a single unit [6].
The idea of making compound engines wasn't new. This idea was used to increase mechanical efficiency of steam plants through the United States for many years [7]. The eighteen cylinder Cyclone motor was supplied with a second power producer which had three possible interchangeable “blow down” units. These units, or turbines respectively, would be geared to the engines crankshaft and they would utilize the escaping exhaust waste gasses velocity to convert it back into mechanical energy [8].
The Wright Aeronautical Division knew that the escaping energy in the form of heat was the loss of possible horse power gain. By adding a blown down unit, it would utilize the wasted gas energy to make the compound engine much more efficient overall. The added blowdown turbine to the unit did not affect the appreciably on the power output of the reciprocating engine cycles [8].
Aircraft's equipped with Turbo Compound
The Lockheed P2V-4 Navy Patrol Airplane was one of the first to use the Turbo Compound. An earlier model of this aircraft with a non Compound Wright motor set a world record for longest flight without refueling. The present P2V-4 now equipped with the Wright Turbo Compound engine has an even greater potential range. As a result, the Turbo Compound was the primary long range potential aircraft for the Navy [1].
The Martin P5M Flying Boat and Fairchild C-119 Cargo plane both used the Wright Turbo Compound engine. This engine has been useed by both military and commercial operators for its dependability, efficiency, and range [1].
References edit
- ^ a b c d Field Engineering Dept.(October 1956). Facts about the Wright turbo compound. Curtiss-Wright Corporation Wright Aeronautical Division
- ^ Gray F. Carroll (2002). The First Five Flights. The Slope and Winds of Big Kill Devil Hill
- ^ California State University (2007). Glenn Curtiss. 1910 Los Angeles International Air Meet
- ^ Borja C. Elizabeth (2010). Curtiss-Wright Corporation Archives. National Air and Space Museum Smithsonian Institution. Washington D.C.
- ^ McCutcheon D. Kimble (2002). Wright J-5 “Whirl Wind” http://www.enginehistory.org/wright_aero.shtml
- ^ Kuhns, Carl (2002). Turbocompounds. http://www.enginehistory.org/Wright/Kuhns/CurtissWrightTC18/TurboCompounds.shtm
- ^ Hobbs S. Leonard (1971). The Wright Brothers and Their Design. Washington DC:Smithsonian Institution Press
- ^ a b Thompson I.G.M., Spence S.W., McCarran C.D. (2009). Design, validation, and performance results of a turbocharged turbo generating biogas engine model. School of Mechanical and Aerospace Engineering. http://www.imeche.org/docs/default-source/turbocharging-papers/2_Design_validation_and_performance_results_of_a_turbocharged_turbogenerating_biogas_engine_model.pdf?sfvrsn=0