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Video Engine Technology
Video Piston Engines
Video Combustion Engine 1
Video Combustion Engine 2
Video Combustion Engine 3
Video Combustion Engine 4
Video Combustion Engine 5
Video Combustion Engine 6
Video Combustion Engine 7
Video Combustion Engine 8
Video Combustion Engine 9

Video Four-stroke Engine
Video Intake Stroke
Video Compression Stroke
Video Combustion Stroke
Video Exhaust Stroke
Video Save energy
Video Compl. dismanteled
Video Aggregate states
Video p-V Diagram 1
Video p-V Diagram 2
Video Fish Hook Curve Diagram
Video Decel. Fuel Shut-off
Video Equaliser Shafts 1
Video Equaliser Shafts 2
Video Inertial forces + -torques
Video Int. Combustion Engine
Video Petrol Engine
Video Diesel Engine
Video Alternative Engines
Video Classic 5-cyl. Engine
Video Classic V8-Engine
Video 6-cyl. Opposed Engine
Video 6-cyl. Opposed Turbo
Video V8 Turbo Engine
Video W12 Engine
Video V8 Ferrari Engine
Video V12 Ferrari Engine
Video Formula-1 Engine (image)
Video Formula-1 Engine
Video Engine Suspension
Video Perf. Measurement 1
Video Perf. Measurement 2
Video Torque Model
Video Torque 1
Video Torque 2

Video Torque 3
Video Stroke-bore Ratio
Video Cubic Capacity
Video Power output p.l.

Video Combustion Engine 1
Video Combustion Engine 2
Video Combustion Engine 3
Video Combustion Engine 4

Video Piston Engine 1
Video Piston Engine 2

          A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

  p-V-Diagram 2

  Cyclic processes  

The diagram shows the course of the pressure through the cubic capacity in the individual strokes. The cubic capacity area is passed through four times, which results in four individual curves. In each case, two of them belong together. The compression- (top left) and the working pressure kurve (top right) are called the high pressure loop, the exhaust- (upper of the two bottom curves) and the intake pressure kurve (lowest) are called the charge changing loop.

The area between the respective curve and the one-bar line (athmospheric pressure) directly above the X-axis, shows the performance which must be gained through the working stroke and the energy which must be put in during the compression stroke. The difference between the two is then, the actually achieved performance, shown by the grey area between the curves.

However, in the four-stroke process, one must also take the area of the charge changing into consideration. After all, the attainable performance is not reduced by only the compressing, but through the intaking and exhausting as well. Should one read these curves (in reality far less smooth) out from an actual engine, one can then determine the real internal performance, and thus, also the efficiency

The above p-V-diagram thus, depicts a basically measurable curve, only, it doesn't always look as smooth as the one shown here. In these curves, faults in the respective engine are shown clearly, e.g., with ignition retard, a shifting of the maximum to the right, and with it, a reduction of the usable performance. 05/10               Top of page               Index
2001-2015 Copyright programs, texts, animations, pictures: H. Huppertz - E-Mail
Translator: Don Leslie - Email:

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