aici - Liceul Tehnologic Holboca - uCoz

(Teacher) “Very good, Diana. And now let’s take a look at the final part of my
presentation The functioning of the engines with internal combustion in four stages. Let’s
remember which are these four stages, Dorin?”
(Dorin) “Stage 1 – admission, stage 2- compression, stage 3 – burning and expansion
and stage 4 – evacuation.”
(Teacher) “Yes, thank you, Dorin .
And now let’s take a look at our computers to see the picture of these four stages,
please! At the stage 1, admission, the piston moves from PMI to PME. The valve A is
open, the valve E is closed. The gas enter the cylinder. At the stage 2, compression, the
valves are closed. The piston moves from PME to PMI compressing the gas. The
volume decreases, the temperature and pressure increase. At the stage 3: a ) Burning
The gas burns. The gas is ignited by the spark plug ( for the engine with spark ignition)
The gas is ignited by the overheating of the air and the injection of the fuel( for the
engine with ignition by compression). b) Expansion The burned gas expends and
pushes the piston from PMI to PME. The valves are closed . The stage 4, evacuation:
The valve E is open, the gas gets out with speed, the pressure on the cylinder
decreases, the piston moves from PME to PMI .
I'd like to end now by summarizing the main points of my talk:
My talk was focused on four main areas. Which are these four main areas , Emilia ?”
( Emilia ) “The four main areas are:
the necessity to study the engine mechanism in the English language.
the presentation of the monocylindric engine , in four stages, with spark ignition.
the components of the engine.
the functioning of the engines with internal combustion in four stages .”
( Teacher ) “Yes , thank you . I'd like to end now by thanking you for your attention.
That’s all I has to say about these subjects for now . If you have any questions I'll be
pleased to answer them now. Any questions or comments?”
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