Simulation in Aerospace

The development of aircrafts, spacecrafts and rockets come under the ambit of aerospace. It is a broad term that refers to the atmosphere and outer space as a single realm. This means that aerospace engineering encompasses both aeronautics (the study of aircraft) and astronautics (the study of spacecraft). Aerospace engineering involves designing of aircrafts and spacecrafts, developing efficient propulsion systems, developing control and guidance systems, and choosing the right material and structures for the aircraft, spacecraft or rockets. It is a team effort that requires scientists and engineers who have a strong foundation in math and science, computer skills and material science. And of course, the expertise and experience to test and validate designs using software tools like simulation.

Behind the Scene
While everyone in India celebrated the success of Chandrayaan 3, there is a lot of R&D that goes on behind the scene for any aerospace project. Scientists and engineers take immense efforts to make aircrafts, spaceships and rockets work exactly as expected. Aerospace projects involve huge budgets and no one can afford failure. Needless to say, engineers use every tool in their arsenal to ensure the successful launch of an aircraft or spacecraft. One such powerful tool is simulation. Simulation is the process of creating a virtual model of a real-world system or process. This model can then be used to study the behaviour of the system or process under different conditions. Simulation plays a crucial role in aerospace engineering and research, offering numerous benefits that contribute to the development, design, testing, and operation of aircraft, spacecraft, and related systems. Below are some important engineering concerns that need to be addressed in aerospace projects and how simulation helps mitigate these challenges:

• Structural analysis: Simulation can be used to analyze the stresses and strains on aircraft structures, such as the airframe, wings, and landing gear. This can help engineers to design structures that are strong and lightweight, and to identify potential weak points.
• Flow analysis: Simulation can be used to analyze the flow of air around an aircraft, as well as the flow of fluids inside the aircraft, such as fuel and hydraulic fluid. Engineers can then improve the aerodynamics of the aircraft, and ensure that the fluids flow efficiently.
• Impact analysis: The impact of birds, hail, or other objects on aircraft structures is a very serious safety hazard.  Simulation helps design aircrafts that are strong enough to withstand these impacts. Composite materials analysis: Simulation can be used to analyze the behaviour of composite materials, which are often used in aircraft structures. This can help engineers to design structures that are strong and lightweight, and that can withstand the harsh environments that aircraft experience.
• Kinematics and multi-body: The motion of aircraft components, such as the landing gear and the control surfaces, and how they interact with each other affects the performance of an aero plane. Kinematics and multi-body simulation ensures that the components move as intended without interfering with each other.
• Aerodynamic and fluid dynamic simulation: Simulation can be used to analyze the aerodynamics of aircraft, such as the lift and drag forces. This helps improve the performance of the aircraft, and to ensure that it is safe to fly.
• Thermal analysis: Simulation can be used to analyze the heat transfer in aircraft, such as the heat generated by the engines and other sources. Engineers can then design structures that can dissipate heat effectively, and prevent the aircraft from overheating.
• Noise and vibration: Simulation can be used to analyze the noise and vibration generated by aircraft. Reducing noise and vibration improves the comfort of passengers and crew.
• Electromagnetic simulation: The aerospace industry relies upon advanced electronic systems for all kinds of communication and tracking. Simulation can be used to analyze the electromagnetic fields generated by the radar and communication systems. This can help engineers to design systems that are safe and efficient.

Here are some other ways in which simulation is beneficial in aerospace:

• Design and Prototyping: Simulations enable engineers to virtually design and test various components, structures, and systems before physically building them. This accelerates the design process and reduces the need for multiple physical prototypes. To meet the extremely stringent design criteria needed to meet strict safety norms, the aerospace sector resorts to a technique called Design for Additive Manufacturing (DFAM). DFAM helps to design components that meet these criteria with light weight options using 3D Printing. It also helps in lattice generation for the structures with various shapes.
• Performance Evaluation: Simulations help assess the performance of aerospace vehicles under different conditions, such as varying speeds, altitudes, and flight maneuvers. This allows engineers to optimize designs for specific performance metrics like efficiency, stability, and aerodynamics.
• Risk Reduction: Simulating complex scenarios and potential failures provides insights into potential issues that might arise during actual flight. This helps identify and mitigate risks before they become critical, enhancing safety.
• Cost Savings: Traditional testing of aerospace systems can be expensive due to the need for specialized equipment and facilities. Simulations reduce the reliance on physical testing, resulting in significant cost savings.
• Environmental Impact: Simulating the environmental impact of aerospace operations, such as emissions and noise levels, helps engineers develop more eco-friendly designs and operations, aligning with modern sustainability goals.

Simulation Software
As mentioned earlier, simulation is used for the designing and testing of new aircrafts and rockets in the aerospace industry. Engineers can use simulation to predict how an aircraft will fly in different weather conditions, such as turbulence and snow.  In case of rockets, engineers need to determine the exact trajectory path and speed, so that the rocket launch is successful. In case the rocket carries any payloads, aerospace engineers need to ensure that they are deployed correctly and function properly for their stipulated lifespan. Simulation plays a pivotal role in all these tasks. How good the simulation result is depends upon which mathematical model is chosen and how accurate the initial data is. That said, the choice of simulation software makes a significant impact on the results too. This is why aerospace companies and space agencies across the world use proven and established software. To cite a couple of examples, Altair HyperWorks™ can be used for structural, thermal, fluid, and multiphysics analysis, while Feko™ is useful in the simulation of wireless systems, EMC (electromagnetic compatibility) and radar applications. It is also useful in antenna design and its placement which is very crucial to effectively communicate GPS location, directional signals, ground signals etc. Inspire™ and Inspire Print from Altair can help in arriving at the right material distribution for the concept design along with thermo-mechanical understanding needed for the 3D Printing process.

The aerospace industry is a dynamic and exciting industry that is constantly evolving. It is expected to grow in the coming years, driven by factors like the increasing demand for air travel, the need for new technologies to explore space and the growth of the defence industry. This in turn will increase the demand for highly reliable simulation software. Since the costs involved in aerospace projects are humongous, it is best to rely on proven software to ensure their success.