V12 Engine !! German Tiger Tank, Soviet Union T-34, North America P-51 Mustang.
Why didn't America sports car such as Chevrolet Corvette or Dodge Viper use V12 engine ??
Ferrari 599 V12 Engine Block. National Geographic Ultimate Factories
Intake Manifold
Tipo F140C. Ferrari Dino Engine
6L, V12, 65°
Lamborghini Murcielago
Rolls Royce-phantom
6.7L, V12, 60°
Aston Martin-Vantage. 007 Movie.
5.9L, V12, ?? degrees
Caterpillar 797 Mining Truck
The Cat 3524B High Displacement engine is built for power, reliability and efficiency for
superior performance in the toughest applications. The Cat 3524B engine is a tandem unit
consisting of two 12-cylinder engines coupled to operate the single engine.
EMD GP 59 Locomotive.
GE 7FDL12 cylinders engine.
North American P-51 Mustang.
Packard V-1650.
27L, V12, 60°. Liquid cooled aircraft engine produced by Rolls-Royce Merlin.
Tiger Tank
Maybach HL230
23L,V12, 60 Water cooled gasoline engine.
T-34. Soviet Union.
According to the Wikipedia:
T-34 has been credited as the most effective, efficient, influential design of WWII.
Diesel Model V-2
??L, V12, 60 degrees. Water cooled diesel engine.
From: http://www.allworldwars.com/T-34%20Tank%20Service%20Manual.html
Thermodynamic cycle which describes the function of a typical spark ignition reciprocating
piston engine. Intake --> Compress --> Power --> Exhaust.
I suddenly found V12 engine fascinating and extraordinary from today extravagant
or high-end sports cars, Caterpillar Mining Truck,Train Locomotives,to WWII.
Royce-Rolls Phantom, Aston Martin-DB9, Ferrari-599, Lamborghini-Murcielago
North American P-51 Mustang (Packard V-1650)
Germany: Tiger Tank (Maybach V12), Panther Tank
Soviet Union: T-34
From P-51 Mustang, Tiger Tank, T-34, we can find the engine is similar which powered
aircraft or tiger. !!!!!! V12 & 60 Degrees !!!!!!
I got the questions is why V12 and 60 Degrees can be used both land and air ???????
V12 Engine can be used on sports car (high rev), truck and train (low rev) which are totally
different characteristics of engine. That's why I obsessed with V12 Engine.
I divided the contents into two major sections. I: History & Application II: V12 Engine Dynamics.
I tried to gather information from the textbook and web and then organized them to be coherent.
~~~~~~~~~~~~~ Engine Dynamics ~~~~~~~~~~~~
1.Engine Balance
The piston and connecting rod which move which move in one direction and then in other direction.
Vibration develops during the operation of the engine.
2.Primary Balance
As the piston passes through TDC and BDC, the change of direction of produced an inertial force due to which the piston tends to move in the direction in which it was moving before the change. This force, called " Primary Force " .
Engine Layout
Single Cylinder : Engine Dynamics, Taiwan Scooter
V-Twin Engine : Ducati, Harley Davidson
Inline 3 Cylinder Engine : Triumph Rocket (U.K)
Inline 4 Cylinder Engine : Most of modern cars, Yamaha R1
Inline 6 Cylinder Engine : BMW 5 Series
V8 Cylinder Engine : Bentley Mulsanne, BMW M3, Dodge Viper, Mercedes-Benz SLS AMG
V10 Cylinder Engine : Porsche Carrera GT, Chevrolet Corvette,
V12 Cylinder Engine : Ferrari 599, Lamborghini Murcielago, Rolls-Royce Phantom
W16 Cylinder Engine : Bugatti Veyron
Flat Engine (Boxer) :
Have you found U.S.A didn't use the " V12 Cylinder Engine " to power WWII tanks or
the modern sports car (Chevrolet Corvette, Cadillac CTS, Dodge Viper) ??????
The picture shows that Direction of Primary Force for single cylinder.
The vibration of the engine can be reduced by adding " Counter-Balance " masses at A and B to exert an outward force with the rotation of the crankshaft. This is undesirable, because it only
shifts the plane of vibration from vertical to horizontal. Therefore, the counter-balance mass
used on the single engine is set to balance only half the reciprocating mass.
Principal parts of slider-crank mechanism. Fourbar slider-crank mechanism
Convert linear motion (piston) into rotary motion (crankshaft).
Reverse: Convert rotary motion into linear motion. (Ballscrew)
A slider-crank as the illustration that converted the reciprocating motion into rotary motion.
Or convert rotary motion into reciprocating motion (Pump)
3. Reciprocating Engine Mechanism
The above equations excerpted from the textbook of Fundamentals of Machine Design
(Robert L. Norton), Ch13 : Engine Dynamics. I ignored the deduction process of the equations
(too abstruse and redundant), so I directly write the results as well as contents.
Equation (a) is an exact expression for the piston position.
Equation (b) is for velocity of the piston.
Equation (c) is for acceleration of the piston.
Let us assume the 4 Stroke Cycle Single Cylinder.
Bore = 3.00, Stoke = 3.54, B/S = 0.85, L/R = 3.50
From (b), we can know the velocity of the piston is zero at TDC or BDC.
TDC:Sin(0) = 0, BDC:Sin(180) = 0.
From (c), we can know the acceleration of the piston is maximum at 0 degree.
"" Superposition "" We will now analyze the dynamic behavior of the single-cylinder
engine based on the approximate kinematic model. Since we have several sources of dynamic
excitation to deal. Use the method of superposition to separately analyze them and then combine
their effects. 1.Forces and Torques 2.Explosive Gas 3.Inertia Forces and Torques
4.Shaking Force and Torques 5.Pin Forces.
Design and Build the perfect engine you need the following knowledge.
Mechanism (Dynamics, Statics): Vibration,
Thermodynamics: Horsepower
Heat and Mass Transfer: Radiator
Fluid Mechanics : (CFD Computational Fluid Dynamics ) Intake Manifold, Exhaust Pipe
Mechanics of Materials : Suitable Material.
Control Engineering : Valve (Honda VTEC), Fuel Injector...
Manufacturing Engineering : Build the components
Computer and Simulation:
CAD (Computer Assist Design), CAE (Computer Assist Engineering)
CAM (Computer Assist Manufacturing),
Bore-Stroke Ratio
The Bore B of the cylinder is essentially equal to the diameter of the piston.
The Stroke S is defined as the distance travelled by the piston from TDC to BDC and is
twice the crank radius, S = 2r.
B/S = 1, Square Engine.
B/S > 1, Over-Square Engine
B/S < 1, Under-Square Engine
Crankshaft Counterweight Design.
Inline Four Cylinders Engine Illustration.
Pistons at which slider motion reverses are called dead center.
Top Dead Center (TDC): As the piston at the top or Maximum distance from the crankshaft.
Bottom Dead Center (BDC): As the piston at the bottom or Minimum distance from the crankshaft.
From left to right of the picture:
The first and fourth pistons are at BDC. The second and third pistons are at TDC.
Flat Plane Crankshaft :
180, 0, 0, 180. As the name suggests, the cranks' pins are at the same plane.
Yamaha R1 uses the " Cross Plane Crank "
Flywheel:
The flywheel mounts at the rear of the crankshaft near the rear main bearing.
This is usually the longest and heaviest main bearing in the engine, as it must support
the weight of the flywheel.
The flywheel stores up rotation energy during the power impulses of the engine.
It releases this energy between power impulses, thus assuring less fluctuation in
engine speed and smoother engine operation. The size of the flywheel will vary with
the number of cylinders and the general construction of the engine. With the large number of cylinders and the consequent overlapping of power impulses, there is less need for a flywheel; consequently, the flywheel can be relatively small. The flywheel rim carries a ring gear, either integral with or shrunk on the flywheel, that meshes with the starter driving gear for cranking the engine. The rear face of the flywheel is usually machined and ground and acts as one of the pressure surfaces for the clutch, becoming a part of the clutch assembly.
Plain Bearing, Journal Bearing. From Confederate Development Room.
I excerpted some paragraph from the article. Basically, it explains why the " Plain Bearing " is
superior than " Roller bearing " as the " Main Bearing " of the crankshaft.
Many people mistakenly believe that because roller bearings offer reduced rotational friction
compared to shell bearings, they must be superior.
In fact the rotational friction of the crankshaft is minimal in the context of other friction sources
in a power train. Roller bearings of a given load capacity are generally larger than a plain bearing equivalent. A larger roller bearing leads to the scaling up of other components creating a non-virtuous spiral of increasing weight.
In an internal combustion motor, the lubricating oil gets contaminated with small particles under
normal operating conditions. These small particles are deadly to the " roller bearing " as they
can get trapped between the bearing and raceway leading to a dent or scratch in the raceway
which in turn will shorten the bearing life and accelerate the failure of the bearing.
Contrast to the " Journal Bearing ", the film of oil that exists between journals in a shell is much
thicker than the equivalent in a roller bearing. The thicker film allows small containment particles
to flow through the shell bearing whereas they would be trapped by thinner film oil in a roller bearing.
It should be noted that roller bearings are more tolerant of less total lubrication which made them
popular before the advent of fully pressurized crank lubrication.
Two pistons at TDC and the other two at BDC. Primary Balance is achieved in this arrangement. The forces on the two pistons at TDC equal to the forces on the two pistons at BDC.
The 1 and 2 pistons develop colckwise turning moment (couple) on the shaft axis.
The 3 and 4 pistons develop counter-clockwise turning moment (couple) on the shaft axis.
The opposing couples counteracted each other by this crankshaft layout preventing the rocking
action of the engine and consequently minimize fore and aft vibration of the engine.
Couple (Mechanics) :
Think about the driver turned the wheel steering.
4. Balance Shaft
From left to right, look at the Connecting Rods.
The 1,4 Connecting Rods are the same direction.
The 2,3 Connecting Rods are the opposite direction of the 1, 4.
The engine has good Primary Balance but poor Secondary Balance. The effect is to produce
a vibration in the vertical plane at a frequency twice that of the speed of the crank.
The horizontal forces had been counteracted by connecting rods.
But, the all four connecting rods created the downward forces to the ground.
Balance Shaft. Saab NG900.
British engineer Frederick Lanchester in 1904 invented Balance Shaft.
The balance shafts are driven by a chain and rotate at twice the crankshaft speed.
Principle of Secondary Balancer
Two counter-balance shafts having offset masses are driven by the crankshaft at twice
crankshaft speed. For four-cylinder in-line engines this is a maximum when at 0, 90, 180,
and 270 degrees rotation of the crankshaft.
(A) At : 0 Degree
Two counter-rotating shafts carry weights and rotate at twice crankshaft speed. They are
timed to coincide with two pistons when they are TDC, and balance out the secondary
force.
(B) At : 45 Degree
In as little as 45' later, B, they are no longer required but they have already turned and in
opposing each other the weights cancel out.
(C) At : 90 Degree
In C at 90' Crankshaft angle they apply an upward force and then cancel out again.
(D) At : 135 Degree
As their force is no longer required. Spinning in this way in light low-pressure bearings and
timed to the crankshaft, the secondary balance shafts were very successful in the
Lanchester but were not adopted generally.
(E) At : 360 Degree
Mitsubishi Motors ‘Silent Shafts’ arrangement incorporates twin counter-balancing shafts
with one shaft higher up the engine than the other. This shaft arrangement damps the
vertical vibration and also the secondary rolling couple, produced when the crankshaft is
rotated by the force of combustion.
** Basically, it is the same as the tail propeller of the helicopter. ??????
The upper shaft rotates in the same direction as the crankshaft and the vertical spacing of
the shafts is 0.7 times the length of the connecting rod. This arrangement of the counter-balance
masses sets up a couple, which opposes the rolling couple. Balance of the rolling couple
throughout the complete engine load range is not possible. Therefore a shaft position is
optimised to minimize the unabalnced couple during the most frequently encountered road load
conditions. The rolling couple of a balanced four-cylinder engine, with this arrangement provides
a better result than that of a six-cylinder unit.
Kawasaki Dual secondary Balancers.
Complementing the engine's perfect primary balance – a characteristic inherent with an In-line Four configuration – dual secondary balancers further reduce unwanted engine vibration, ensuring a supremely smooth engine.
The Porsche 944 engine installs a double-sided toothed belt, to drive the counter-balance shafts. The balancer system on this engine reduces the noise level by 20 dB. When the secondary vibration, especially at high engine speed is minimized, it provides a reduction of the ‘boom’, which is felt and heard in the passenger compartment.
Ford has used a Secondary Balancing system, apparently of their own design, in the 2.3DOHC engine. The two shafts are set at the same height but below the crankshaft, in bearings in the sump immersed in the oil. Plastic covers over the counterweights prevent foaming in the oil, and the shafts are driven by helical gears and a simplex chain from the crank sprocket. It is in this way that they have produced a very refined, smooth engine with all the advantages of weight saving, size and simplicity over a 6. The resulting engine is mechanically similar to the DOHC2000 but with a larger bore and with an increased height because of the balancer module.
Honda 2.0L DOHC i-VTEC
Dual Balance Shafts located below the crankshaft.
Kawasaki ZX-6
Ducati 1098
1,099 cc, 90° V-twin Cylinder, 4 valve per cylinder Desmodromic, liquid cooled.
Bore x Stroke : 104 mm (4.1 in) x 64.7 mm (2.5 in), Over-Square
Ducati 1199 Panigale
This CAD drawing reveals the desmodromic valve actuation and the chain/gear assembly
that drives them. Note also the “auto-decompressor” on the end of the exhaust camshaft.
It opens the valve slightly at tick-over to ease startup.
**A 90 degrees V-Twin engine with a single crank pin for both connecting rods can be balanced, but fires at uneven alternate intervals of 270 and 450 degree of crankshaft rotation.
Harley-Davidson VRSC
In the multi-cyliner reciprocating engine piston devices, such as compressor or engine.The cylinders in the " V " arrangement is more compact than in a straight row, or diametrically opposed to one another.
**A 60 degrees V-Twin engine with a single crank pin for both connecting rods can be balanced,
but fires at uneven alternate intervals of 300 and 420 degree of crankshaft rotation.
1130cc, 60° V-Twin Cylinder, 4 valve per cylinder, liquid cooled.
Bore x Stroke : 100 mm (3.94 in) x 72 mm (2.83 in)
Compression Ratio 11.3 :1 nominal
2002 Harley-Davidson Revolution Engine
The above picture and following information is United States Patent.
Even Firing, Fully Balanced, V-Twin Engine. Paten No : US 6,895,919 B1.
A V-Twin includes a two cylinders reciprocating apparatus, having a pair of connecting rod journals that are centered at a common throw radius from the crankshaft axis, and angularly displaced from one another along the throw radius by an angular displacement equal to an included angle defined by axes of the cylinders.
So that the pistons will move in unison and each reach Top Dead Center (TDC)
and Bottom Dead Center (BDC) in their respective cylinders at simultaneous time.
Counterweights on two balance shafts rotate in a 1:1 rotation ratio in a direction opposite to the
crankshaft, with forces from the balance shaft counterweights and the crankshaft counterweight
alternatively aligning and opposing for counterbalancing vertical forces and unbalance loads in
the engine.
From above picture, we can see two pistons area at TDC, the two balance shafts will counteract
the vertical forces of two connecting rods produced.
54, 56 are Balance Shafts.
Both pistons located at BDC.
Moto Guzzi Griso 8V
Compare Moto Guzzi Griso 8V to " Ducati 1098 " and " Harley-Davidson VRSC".
Look at the layout of the V-Twin engine.
Transverse Crankshaft Mounting : Ducati, Harley Davidson
Longitudinal Crankshaft Mounting : Moto Guzzi
Longitudinal Crankshaft Mounting. Moto Guzzi Griso 8V
Driveshaft drives the rear wheel. BMW also used the same mechanism. This orientation is suited to shaft drive, eliminating the need for a 90° bevel gear at the transmission end of the shaft.
I have written very redundant articles for the engine, now the trek will explore the pith of the
V12 engine. But, don't rush up. Let me introduce the " Inline 3 Cylinder Engine ",
" Inline 6 Cylinder Engine ", and then " V12 Engine ".
Let Eagles Band get me through the bumpy odyssey and keep on running.
How about The Long Run, Life in the Fast Lane, Learn to be Still, Take it Easy ...... ??
Triumph Rocket iii
2294.00 cc, Inline 3 Cylinder Engine
Bore x Stroke : 101.6 mm (4.0 in) x 94.3 mm ( 3.7 in)
In a 3 Cylinder Engine with throws at 120' the Secondary Forces cancel out.
Although three cylinders sounds odd, in fact it has a very good Primary and Secondary balance:
the one piston exerting force is balanced by the other two.
The picture illustrates the crankshaft layout and the primary forces when piston 1 is at TDC. In this case the crank throws are set at 120 degrees; therefore the large force at each of the dead centers is balanced by the two smaller forces on the other two pistons. These smaller forces are caused due to acceleration or deceleration of the piston as it approaches or leaves the end of the stroke.
Since a V6 or Straight 6 engine can be seen as a double 3 cylinder engine, this explains why it is much smoother than a four cylinder engine of the same capacity and why it is used in more expensive cars where refinement is expected.
BMW M3 Inline Cylinder Engine Cutaway.
Basically, you can imagine that you use AutoCad " Mirror Command " to replicate the
Inline 3 Cylinder Engine to become the Inline 6 Cylinder Engine.
BMW 535i Engine Skeleton.
Ferrari 599 GTB Fiorano V12 Cylinder Engine
That's why V12 Cylinder is extremely so perfect !!
I can't see the pictures :(
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