The traditional structure of the bottom shaft of a jet turbine engine

Intake ducts, compressors, combustion chambers and turbines, nozzles and afterburners.

Summary. Yes, the turboshaft engine is a type of air-aspirated engine<> is the turboshaft engine an air-aspirated engine.

The turboshaft engine is a kind of aspirated engine, and the turbo ramjet combined engine is a combination <> turbo engine. According to the combination of turbine engine and ramjet engine, it can be divided into split and integral combination of open bird engine, in which the integral combined engine is divided into series layout and parallel layout according to the relationship and process of the main components of the turbine and ramjet engines. In the turboramjet combination engine, the ramjet engine is divided into sub-combustion, scramjet and dual-combustion ramjet engines according to their working modes.

I hope it will be helpful to the kiss<>

High-speed turbine engines are generally used to reduce friction

Full floating bearing, can only transmit torque, friction to a minimum;

Angular contact ball bearings are only used to withstand other moments, and axial thrust is mainly carried by thrust bearings.

Without a rotor, the lubricating oil of the pressure is used to fill these two gaps, so that the floating bearing rotates in the same direction with the rotor shaft in the oil film, and its speed is much faster than that of the rotor shaft. Fully floating bearings are mainly used in high speeds, only transmit torque, and do not bear any reaction force and bending moment.

You can go to the electromechanical shop and ask for it.

Inhale! Compress! Burn! Squirt backwards!

Due to the different valve actuation forms and camshaft positions, the composition of the valve actuation group is also very different.

Camshaft. Working conditions and materials of camshafts.

Cam bearings are subjected to periodic shock loads. The contact stress between the cam tappet and the cam tappet is very large, the relative sliding speed is also very high, and the cam working face is seriously worn.

Camshaft construction.

The camshaft is supported in the bearing hole of the camshaft by the camshaft journal, so the number of camshaft journals is an important factor affecting the stiffness of the camshaft support. If the camshaft is not rigid enough, it will bend and deform during operation, affecting the valve timing. The lower camshaft is fitted with a camshaft journal every 1 2 cylinders.

The working principle of the camshaft is controlled by the intake and exhaust valve opening and closing time, duration and speed car on the camshaft, respectively. The cam profile of a low-speed engine consists of several arcs, called arc cams. The high-speed engine uses a function cam, the profile of which consists of a certain functional curve.

o is the center of rotation of the camshaft, the ab and de segments on the cam profile are the buffer sections, and the BCD segments are the working sections. The tappet starts to rise at point A, stops moving at point E, and the cam turns to a point in the AB segment, so that the valve clearance is eliminated and the valve begins to open. Thereafter, as the cam continues to rotate, the valve gradually opens, the valve opening reaches its maximum at point C, then the valve gradually closes, and the differential excitation at a certain point in the de segment the valve closes completely, and then the valve clearance is restored.

The valve opens at point B at the latest and closes completely at point D at the earliest. Since the valve is in the buffer section where the cam lift changes slowly when it begins to open and close, its movement speed is small, so it can prevent strong shocks.

The relative angular position of each cam of the same name (each intake cam or each exhaust cam) on the camshaft is related to the direction of rotation of the camshaft, the working sequence of the engine, the number of cylinders or the angle of the working interval. If you look at the fan side of the engine and the camshaft rotates counterclockwise, then the working zone angle of a four-cylinder engine with the working sequence 1-3-4-2 is 720 4 = 180 crankshaft angle, which is equivalent to 90 camshaft angles, that is, the angle between the cams of the same name is 90. For a six-cylinder engine with a working sequence of 1-5-3-6-2-4, the angle between the cams of the same name is 60.

The relative angular positions of the intake cams and exhaust cams of the same cylinder, i.e. the relative angular positions of cams with different names, are determined by the valve timing and the direction of rotation of the camshaft.