Challenge

Bird Strike - Project - 2

AIM:-To stimulate non-linear transient birdstrike stimulation where the bird tries to hit the gas turbine blade by using Lsdyna.

THEORY:-

The turbojet engine consists of four sections—compressor, combustion chamber, a turbine section, and exhaust.
The compressor section passes inlet air at a high rate of speed to the combustion chamber.
The combustion chamber contains the fuel inlet and igniter for combustion.
The expanding air drives a turbine, which is connected by a shaft to the compressor, sustaining engine operation.
The accelerated exhaust gases from the engine provide thrust.
It works under the process of ideal Brayton cycle.

isentropic process – ambient air is drawn into the compressor, where it is pressurized.
isobaric process – the compressed air then runs through a combustion chamber, where fuel is burned, heating that air—a constant-pressure process.
isentropic process – the heated, pressurized air then gives up its energy, expanding through a turbine (or series of turbines). Some of the work extracted by the turbine is used to drive the compressor.
isobaric process – heat rejection (in the atmosphere).

Bird Strike is common and can be a significant threat to aircraft safety.
For smaller aircraft, significant damage may be caused to the aircraft structure and all aircraft, especially jet-engined ones, are vulnerable to the loss of thrust which can follow the ingestion of birds into engine air intakes. This has resulted in a number of fatal accidents.
Bird strikes may occur during any phase of flight but are most likely during the take-off, initial climb, approach, and landing phases due to the greater numbers of birds in flight at lower
levels. Since most birds fly mainly during the day, most bird strikes occur in daylight hours as well.

PROCEDURE:-

Now we need to create the material card.
Here we need to open a new file and we need to create material and section for every part and save it with a duplicate id.

Where we considered rpm as 5000

p=2`pi`NT/60 where p=0.5 rad/ms.

velocity =20 mm/ms

Then we need to give contacts in different. k for contacts.
There are four contacts one is between blade and hub, blade and casing, blade and bird
And other is between the blades which are single surface contact.

Where here I increased the time step directly so that my stimulation took 20 minutes to complete.

RESULTS:-

Here the energy is a balance where the kinetic energy of the component is not much drop in energy.
Where the kinetic energy of the component is 612.428 Kg mm^2/ms^2.
As the kinetic energy decreases where is there is a drop-in velocity so the strain energy increases.
The impact happened at 0.8ms where there is a constant rise in internal energy and the after 2ms the energy is constant.

As we can see that the plastic has occurred in the model we there is an increase of 4% of strain and it be coming to its original position due to the material is elastoplastic.

The plot is taken for the bird where the maximum force exerted is 0.6 kg mm/ms^2 absorbed.
Where we see that it attained high force at 2ms then after it decreases gradually where the force is been totally absorbed and injury is high.

There we can see the energy master and salve are the same from that I can understand there no penetrations occurred.

The stress where the bird impacted the blade at 1ms we can there is high stress is generated and we can say the impact is low.
Because I considered velocity of the bird 20 m/s where in reality it will be high.

CONCLUSION:-

Understood how to perform deck for stimulation.
Understood performed bird strike stimulation in ls dyna.
From this, I can say that the bird was injured highly it absorbed high energy
The blade got the deflection of the element it been 120mm which was less when compared to the dimensions of the blade.

Ship work like this
in your own course.