Aerospace engineering involves the mathematics and physics involved behind the development of aircrafts. It encompasses mechanics and physics of fluids, aerodynamics, structures and materials, instrumentation, control systems, automation, propulsion and energy conversion, aeronautical systems, and a whole lot more. As you can see, there is a huge amount of engineering effort that works in unison behind the scene to make your airplane ride comfortable, fast and safe. Colleges in India and other nations even offer degree courses dedicated to Aerospace engineering. Let us now cover the salient aspects of aerospace engineering very briefly:
Aerodynamics is the discipline that studies the forces and the resulting motion of objects in the air. Indeed, the sight of an airplane flying overhead that fascinated most of us as children typifies the laws of aerodynamics in action, and it is difficult to comprehend that a scant 150 years ago, such flying machines were considered....well, a real flight of fancy. The word ‘aerodynamics’ encompasses a lot of engineering topics, that includes fluid dynamics, Bernoulli’s theorem, Euler’s equation and Inviscid Fluid Motion, Navier and Stokes equations, Reynolds’ equation for viscous, laminar and turbulent flow, the circulation theory of lift and many other engineering and mathematical theories. For proper aircraft design, it is essential to optimize all the aerodynamic parameters that make an airplane fly, and this is not really possible without high end simulation tools – like those from Altair as an example – and an expertise in analyzing the results.
The importance of materials science and technology in aerospace engineering cannot be overstated. From the fuselage, wings, to the control panels and seats, each and every component of both commercial and defence aero planes are carefully selected. There are two major reasons why material selection matters - one because weight plays an important role in mileage of the aircraft, and two the safety of the plane is of paramount importance. Aero planes can encounter severe turbulence (more on this later), and material selection plays a climacteric role in the safety of the aircraft. Choosing the correct material impacts the entire life cycle of an aircraft, from the initial design phase through to manufacturing and certification of the aircraft, to flight operations and maintenance and, finally, to disposal at the end-of-life.
Composite materials, which are a combination of two or more materials, have grown in importance in aerospace engineering. Composite materials are useful in reducing the weight of an airplane, which in turn saves precious fuel, imparts strength while being lightweight, and reduces wear and tear, saving replacement cost. Here are the properties of aircraft material that affect its performance:
- Physical properties like density
- Mechanical properties like ductility, stiffness, plasticity, fatigue and strength
- Chemical properties like corrosion and oxidation
- Thermal and electrical conductivity
The main materials used by the aerospace sector include steel, aluminium and titanium alloys, and fibre reinforced composites. Composite materials like carbon fibre are lightweight and reduce fuel costs and improve aerodynamics. Metal hybrid compounds are good conductors of electricity and when used in the outer shell dissipates electricity from lighting strikes, protecting passengers. In general, the use of composite material is on the rise for their superior mechanical and chemical properties.
As mentioned above, turbulence is part and parcel of flying, and the stability of an aero plane is important for its safety as it hurls at speeds that exceed 800 km / hr. There are various types of turbulences that affect an airplane. Clear air turbulence is caused by blowing wind or jet streams. Other kinds of turbulence include “wake turbulence”, which forms behind an aircraft when it flies through air, creating wingtip vortices. Vibration analysis, based on an amalgamation of mathematics and physical observation, is an engineering service offered to mitigate the effects of turbulence, jet engine propulsion and other factors that may cause the aircraft to vibrate. A vibrating system like an aircraft fuselage must have a component that stores potential energy and releases it as kinetic energy in the form of motion (vibration) of a mass. The motion of the mass then gives up kinetic energy to the potential-energy storing device. A common and very effective way to reduce transient and steady-state vibration is to increase the amount of damping in the system so there is greater energy dissipation. This is especially useful in aerospace structures applications, where the added mass of an absorber system may not be practical. Again, only thorough engineering analysis can help aerospace engineers to arrive at an optimal solution for minimizing vibrations.
Apart from these, other parameters that require engineering consideration are simulation of launching loads, computational fluid dynamics, thermal and flow simulation, kinematic and multi-body dynamic simulations, etc.
Aerospace Engineering Services
We have just touched a few topics related to aerospace engineering. Irrespective of whether the aero plane is commercial or used by defence forces, a careful analysis and evaluation of all the parameters that can affect its performance need to be undertaken before production. Aircraft manufacturing is a serious business; a single success or failure can make or break the company. The development of aero planes involves a full-fledged team of engineers and designers that need to have an understanding of the physics and math behind the flying machines. Thanks to advanced simulation tools and 3D printing technology, it is now possible to reduce the development time. However, making proper use of the full potential of the simulation software requires knowledge of that software, and an in-depth expertise in aerospace engineering. There are engineering service providers in India that specialize in aerospace engineering, and many manufacturers prefer to rope in their services for the know-how and experience their team brings in for the best possible aero plane design.