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Home , Diesel cycle, Duesenberg Model J, Siegfried Marcus

A short Course in Energy Conversion Session 5 Jim Rauf

OLLI Fall 2019 1 Internal Fire, Smoke and Noise

• Piston engines • -Spark Ignition • Diesel Cycle-Compression Ignition • engines • Gas Turbines • Jet engines • Rocket Engines • Liquid • Solid Fuel • Fire Arms

OLLI Fall 2019 2 Internal Combustion Piston Engines

• 1680 - Dutch physicist, Christian Huygens • 1862 - Alphonse Beau de Rochas, a French designed (but never built) an internal civil engineer, patented but did not build a combustion that was to be fueled four- engine with gunpowder • 1864 - Austrian engineer, Siegfried Marcus, • 1807 - Francois Isaac de Rivaz of built a one-cylinder engine with a crude Switzerland invented an internal , and attached his engine to a combustion engine that used a mixture of cart for a rocky 500-foot drive hydrogen and oxygen for fuel • Several years later, Marcus designed a vehicle that briefly ran at 10 mph • 1858 - Belgian-born engineer, Jean Joseph Étienne Lenoir invented and patented • Some historians have considered it the forerunner of the modern automobile by (1860) a double-acting, electric spark- being the world's first -powered ignition internal combustion engine fueled vehicle by coal gas • In 1863, Lenoir attached an improved • 1866 - German engineers, Eugen Langen engine (using petroleum and a primitive and Nikolaus August Otto improved on carburetor) to a three-wheeled wagon that Lenoir's and de Rochas' designs and managed to complete an historic fifty-mile invented a more efficient gas engine road trip

OLLI Fall 2019 3 Internal Combustion Piston Engines

• 1876 - Nikolaus August Otto invented and later patented a successful four-stroke engine, known as the "Otto cycle" • 1885 - invented what is often recognized as the prototype of the modern gas engine • It had a vertical cylinder, and with gasoline injected through a carburetor (patented in 1887) 1886 Daimler Motor Carriage • Daimler first built a two-wheeled vehicle the "Reitwagen" (Riding Carriage) with this engine • A year later he built the world's first four-wheeled motor vehicle • 1886 - On January 29, Karl Benz received the first patent for a gas-fueled

1886 Benz Patent Motor Car

OLLI Fall 2019 4 Internal Combustion Piston Engines- Otto Cycle

• Spark Ignition Engine (SI) Otto Cycle • In 1867, Nicolaus August Otto, a German engineer, developed the four-stroke "Otto" cycle • He patented it • The Otto Cycle has been widely used in transportation • Automobiles • Trucks • Boats • Aircraft http://www.animatedengines.com/otto.html • It uses gasoline for fuel • The fuel-air mixture is throttled and is ignited by electrically by a

OLLI Fall 2019 5 Internal Combustion Piston Engines -Otto Cycle

Ideal Otto Cycle

Actual Otto Cycle

OLLI Fall 2019 6 Internal Combustion Piston Engines- Otto Cycle

• 1925-1926 lightweight, air-cooled radial • The R-4360 had a Displacement of engines were introduced 4,362.50 in³ • Revolutionized aviation by making bigger, • Initial models developed 3,000 HP final faster planes possible models delivered 4,300 hp using two large in addition to the • The final development of the air cooled radial aircraft IC engine: • They weighed 3,482 to 3,870 lbs • Pratt &Whitney R-4360 a 28-cylinder four- row radial engine • Power/weight ratio of 1.11 hp/lb matched by very few engines • 18,697 were built between 1944 and 1955 • Applications included: • Boeing C-97 • Douglas C-124 • Fairchild C-119 • Boeing B-50 • Consolidated B-36 bombers • Boeing 377 Stratocruiser

OLLI Fall 2019 7 Internal Combustion Piston Engines-

• Atkinson cycle is a modified Otto cycle engine in which the intake valve is held open longer than normal to allow a reverse flow of intake air into the intake manifold • The effective is reduced but the expansion ratio is unchanged • The goal of the modern Atkinson cycle is to allow the in the combustion chamber at the end of the power stroke to be equal to atmospheric pressure • All the available energy has been obtained from the combustion process • A number of hybrid automobiles used the Atkinson cycle

OLLI Fall 2019 8 Internal Combustion Piston Engines- Atkinson Cycle

• Atkinson cycle is a modified Otto cycle engine in which the intake valve is held open longer than normal to allow a reverse flow of intake air into the intake manifold • The effective compression ratio is reduced but the expansion ratio is unchanged • The goal of the modern Atkinson cycle is to allow the pressure in the combustion chamber at the end of the power stroke to be equal to atmospheric pressure • All the available energy has been obtained from the combustion process • The disadvantage versus the Otto cycle is reduced power density • A number of hybrid automobiles used the Atkinson cycle • A smaller portion of the compression stroke being devoted to compressing the intake air, an Atkinson cycle engine does not take in as much air as would a similarly designed and sized Otto cycle engine

OLLI Fall 2019 9 Internal Combustion Piston Engines –Diesel Cycle

• Compression Ignition Engine (CI) No spark plug Diesel Cycle • The came about in 1892 by German engineer, Rudolph Diesel • Uses diesel fuel (kerosene) • Fuel injected into cylinder • Air not throttled • Fuel-air mixture is auto- ignited due to high temperature of fuel-air mixture • Generally lower speeds than Diesel engine SI engine • Higher efficiency than SI Diesel cycle is widely used in transportation engine and stationary applications • Trucks • • Electric generation

OLLI Fall 2019 10 Internal Combustion Piston Engines –Diesel Cycle

Ideal Diesel Cycle Actual Diesel Cycle

Modern passenger car diesel engines may have efficiency of up to 43% Engines in large trucks, and buses can have peak efficiencies around 45% Large two stroke diesel engines have achieved efficiency up to 55%

OLLI Fall 2019 11 Internal Combustion Piston Engines

SI and CI Engine Comparison

Diesel cycle engines tend to have higher torque, lowe power and lower fuel consumption than Otto cycle engines

OLLI Fall 2019 12 Internal Combustion Piston Engine Comparison

• 1929 Model J • 265 hp • 420 cu in (0.63 hp/cu in) • Straight 8 cylinder • DOHC • 4 valves/cylinder • 5.7:1 CR • 2019 Chevrolet Corvette • 455 hp • 378 cu in 1.2 hp/cu in) • V 8 cylinder • OHV • 2 valves/cylinder • 11.5 : 1 CR

OLLI Fall 2019 13 Internal Combustion Piston Engine Comparison

1908-1927 Model T 2019 Mustang Configuration I-4 I-4 Fuel delivery Carburetor Direct Injection Turbo charged Block and Head Cast Iron Aluminum Displacement 177 cu in 138 cu in /Stroke 3.75/4.00 in 3.45/3.70 in Compression ratio 3.98:1 9.5:1 2 valves/cylinder 4 valves/cylinder Cam in block DOHC Side valve(flat head) Twin variable cam timing Ignition Ditributor less-coil on plug Horsepower 20 HP @ 1500 RPM 310 HP @ 5500 RPM

Torque 83 ft lb @900 RPM 350 ft lb @ 3000 RPM MPG 13-21 mpg 21-31 mpg Top speed 45 mph 145 mph

OLLI Fall 2019 14 Two Stroke Internal Combustion Engine

OLLI Fall 2019 15 Increasing the Power Output from Piston IC engines

• Increase the compression ratio of the • Supercharger engine • Air pump driven mechanically from • CR= of cylinder/volume of the engine by belts, chains or gears combustion chamber • Increase RPM of the engine • Power is /time • Reduce pressure losses in the intake and exhaust paths • Larger valves • Soother flow passages • Reduced exhaust back pressure • Increase the mass of air in the cylinder – allows increased amount of fuel to be burned –more energy converted Centrifugal supercharger • Increase the displacement of the engine- larger pistons/longer stroke • Pump more air into cylinders • Supercharger •

OLLI Fall 2019 16 Increasing the Power Output from Piston IC engines

• Turbocharger is a centrifugal compressor driven by a small gas turbine that uses the piston engine to generate the hot gases to drive the turbine • Turbo chargers first used on airplane engines to increase power at high altitude ( air is less dense at altitude) • Turbocharger • Pumps air into cylinders • Driven by exhaust gases from engine • Uses some of the energy in the engine’s exhaust gases • No mechanical connection with engine

OLLI Fall 2019 17 Internal Combustion Engines -Brayton Cycle

• In 1872 George Brayton patented an internal combustion stationary engine known as Brayton's Ready Motor • The engine had one cylinder for compression, a receiver reservoir, and a separate power cylinder in which the products of combustion expanded for the power stroke. • The significant difference is that the two cylinders are arranged so that the fuel/air mixture burns progressively at constant pressure as it is transferred from the compressor cylinder and reservoir to the working cylinder • Constant pressure combustion • The constant pressure combustion gas turbine engine is referred to as the Brayton Cycle Engine

OLLI Fall 2019 18 Internal Combustion Engines -Brayton Cycle • Brayton cycle is used to describe several configurations of gas turbine engines and jet engines • Stationary gas turbine engines-shaft power • Gas turbine engines used in transportation-shaft power • Turbojet engines-jet exhaust • Turbo fan jet engines-fan and jet exhaust

OLLI Fall 2019 19 Gas Turbine Components

• Inlet • Directs air into the compressor • Compressor • Increases pressure (and temperature) of the air • Combustor • Fuel injected into air leaving the compressor is burned at ~constant pressure • Turbine (compressor drive) • Converts thermal energy in the high temperature /pressure combustion products from the combustor into mechanical energy(shaft rotation) by expansion of the gas to lower pressure/ temperature • Power turbine (free turbine) • Not connected to upstream components • Converts energy left in the gas after it expands thru the compressor drive turbine into mechanical energy (shaft rotation) by expanding the gas to a lower pressure/temperature • Power turbine is source of power • Exhaust • Directs to atmosphere or to

OLLI Fall 2019 20 Gas Turbines • Stationary industrial power

Output (MW): 261 simple cycle Baseload Efficiency: 37.3 % Start Time (minutes/Hot Start): 15 simple cycle Combustion Interval (hours/starts): 24k/450 HGP Interval (hours/starts) - 24k/900 Rotor Life (hours/starts): 144k/5000

GE 9FA Heavy Duty Gas Turbine

OLLI Fall 2019 21 Gas Turbines

• Advantages of gas turbine engines • Very high power to weight , compared to CT7 reciprocating engines 1536-2380 HP 400-537 Lbs • Smaller than most reciprocating engines of 3.84 -4.48 HP/Lbs the same power rating Diesel turbocharged V8 • Rotational direction only, with far less 330 HP vibration than a 835 Lbs • Fewer basic moving parts than 0.40 HP/Lbs reciprocating engines • Disadvantages of gas turbine engines • Waste is dissipated almost entirely in the exhaust-no external cooling system • Cost is very high required • Less efficient than reciprocating engines at idle speed • This results in a high temperature exhaust stream that is very usable for boiling water • Especially diesel engines for steam turbine in a combined cycle • Longer startup than reciprocating engines power plant • Less responsive to changes in power • Relatively low operating demand compared with reciprocating engines • Low lubricating oil cost and consumption- not contaminated during operation • Can run on a wide variety of OLLI Fall 2019 22 Jet Engines

• 1937 Sir Frank Whittle in England and Hans von Ohain in Germany construct the first turbojet propulsion engines.

OLLI Fall 2019 23 Jet Engines

• Convert chemical energy to mechanical • The energy left in the gas after it energy to propel aircraft exhausts from the turbine is converted into of the • Burn fuel in combustor to generate high gas which is used to propel the temperatures-thermal energy aircraft • Convert thermal energy of hot gas into • Newton’s third law- mechanical energy by expanding hot gases action/reaction thru a turbine • As the gas pressure and temperature decreases, the energy of the gas drives the turbine • The energy extracted from the gas by the turbine drives the compressor which “pumps up” the air coming into the engine which is then combined with fuel in the combustor and burned to add energy in the form of thermal energy(heat) to the gas in the combustor

OLLI Fall 2019 24 Jet Engines-Turbofan

OLLI Fall 2019 25 Jet Engine High Pressure Turbine Airfoils

OLLI Fall 2019 26 HPT ~75,000 HP

~1000 g’s@HPTR rim

LPT ~55,000 HP

OLLI Fall 2019 27 Commercial Turbofan Engines

JT3D 707 engine GE90 777 engine 18,000 lbs thrust 115,000 lbs thrust

OLLI Fall 2019 28 Commercial Jet Engine Development

Typical subsonic cruise, 80% throttle, min SFC Turbofan efficiency GE90 36.1% PW4000 34.8% PW2037 35.1% (M.87 40K) PW2037 33.5% (M.80 35K) CFM56-2 30.5% TFE731-2 23.4%

Propulsive efficiency (ηp) measures the effectiveness of a propulsive device in converting mechanical power input to propulsive power output

OLLI Fall 2019 29 Rocket Engines

• In a rocket engine fuel and stored oxidizer are ignited in a combustion chamber • The combustion produces great amounts of exhaust gas at high temperature and pressure • The hot exhaust is passed through a nozzle which accelerates the flow • The flow of gases exiting the nozzle creates a force in the opposite direction on the engine according to Newton’s third law of motion • This is the same principle as in a jet engine

OLLI Fall 2019 30 Rocket Engines

• The earliest rockets were military solid fuel , gunpowder , rockets • Robert Goddard achieved the first successful flight with a liquid- propellant rocket on March 16, 1926. • Fueled by liquid oxygen and gasoline, the rocket flew for only two and a half seconds, climbed 12.5 meters, and landed 56 meters away in a cabbage patch • Like the first powered airplane flight by the Wright brothers in 1903, Goddard's gasoline rocket was the forerunner of a whole new era in rocket flight

OLLI Fall 2019 31 Rocket Engines

• Solid propellant rockets have fuel and oxidizer in a solid mixture within the rocket that is burned to create the gases that propel the rocket • Gunpowder rockets are an example of solid fuel rockets • Generally cannot be stopped or throttled until burnout • Liquid propellant rockets have oxidizer and fuel in liquid form that are introduced into the combustion chamber to be burned to create gasses that propel the rocket • May be stopped/started/throttled • Are more complex than solid fuel rockets • Have higher specific impulse- efficiency

OLLI Fall 2019 32 Rocket Engines

Saturn V rocket S1C stage used 5 F-1 engines Thrust = 7.6 million pounds

OLLI Fall 2019 33 Firearms

• A firearm is a special type of piston heat • Modern gun cartridges use "smokeless" engine powder that is relatively stable, of uniform quality, and leaves little residue when • The bullet has a function of a piston ignited • Rapid burning of the powder charge creates • For centuries, "black powder" was used and high pressure gas that acts on the bullet was quite volatile (ignited at low forcing it out the barrel temperature or shock), was composed of irregularly sized grains, and left a heavy • Force =Pressure x Area residue after ignition, requiring frequent • The efficiency of a firearm strongly depends cleaning of bore on its construction, especially on its caliber • The powder is ignited by a primer, a volatile (bullet diameter) and barrel length substance that ignites when struck to detonate the powder in a cartridge • Energy balance of a typical small firearm for .300 Hawk ammunition : • "Rimfire" cartridges have primer inside the base • Barrel friction 2% • “Centerfire" cartridges have primer in a • Hot gases 34% hole in the middle of the base of the • Barrel heat 30% • Unburned propellant 1%. cartridge case • Energy of bullet 33%

OLLI Fall 2019 34 Firearms

This is a graph for the 5.56 mm NATO round, being fired through an 18-inch barrel The horizontal axis is bullet travel in inches The left vertical axis is pressure (red line) The right vertical axis is bullet velocity (blue line) Time to reach the muzzle is about 1 milisecond

OLLI Fall 2019 35 •Electrical Energy Atoms Electrons Electric current Electric potential Magnetism Generators Motors Batteries Fuel cells Thermoelectric effect Photoelectric effect Photovoltaic effect

OLLI Fall 2019 36