Multiphysics Simulation and Design Companies

Multiphysics simulation refers to the computational modelling of systems where multiple physical phenomena (or "physics") interact simultaneously. These interactions can involve combinations of mechanical, thermal, fluid dynamic, electromagnetic, acoustic, and chemical processes. Since real-world engineering problems often involve coupled physical effects, multiphysics simulations provide a more accurate representation than single-physics models.

 Key Aspects of Multiphysics Simulation:
Simultaneous or Sequential Solving: The problem can be solved using:

• Direct coupling (strong coupling): All equations are solved simultaneously.
• Indirect coupling (weak coupling): Each physics phenomenon is solved separately, with data exchanged iteratively.

Multiphysics analysis is used extensively in sectors like aerospace, automotive, marine, railways, energy, biomedical, heavy industries and civil engineering, where complex interactions occur.

Simulation Approach:  

• CFD (Computational Fluid Dynamics) models shock waves and air heating. 
  
• Thermal Analysis predicts heat distribution on the vehicle surface. 
  
• Structural Analysis evaluates thermal expansion and material stress.  

Importance: Ensures thermal protection systems (e.g., heat shields) can withstand re-entry conditions.

 2. Ships: Hydro-elasticity of Ship Hulls in Rough Seas  

• Physics Involved: Fluid-structure interaction + Structural dynamics 
  
• Problem: Waves exert dynamic pressures on a ship’s hull, causing vibrations and fatigue.  

Simulation Approach:  

• CFD models wave impacts and hydrodynamic loads. 
  
• Finite Element Analysis (FEA) predicts hull deformation and stress.
• Two-way coupling ensures fluid forces affect structure and vice versa.  

Importance: Prevents hull failure and optimizes design for fuel efficiency and safety.

 3. Railways: Pantograph-Catenary Interaction in high-speed trains  

• Physics Involved: Electromagnetics + Structural dynamics + Contact mechanics
• Problem: The pantograph (current collector) must maintain constant contact with the overhead wire (catenary) for power supply, even at high speeds.  

Simulation Approach:  

• Multibody Dynamics models mechanical vibration. 
  
• Electromagnetic Simulation ensures proper current collection.
  
• Contact Mechanics prevents arcing and wear.  

Importance: Ensures reliable power transmission and reduces maintenance costs.

Computing Power and Multiphysics Simulation
As computing power has advanced, multiphysics simulations have become more sophisticated, enabling engineers to solve complex, coupled problems with higher accuracy and efficiency. Altair, a leading provider of simulation software for example, leverages modern computational capabilities to enhance multiphysics modelling across industries such as aerospace, automobile, marine, and railways. The key aspects of multiphysics that depend on computing power include model resolution, solver efficiency, coupling methods, and real-time / post-processing capabilities.

What are Solvers?
Solvers are computational engines that perform the mathematical calculations required to simulate physical phenomena. They take input data (such as mesh geometry, material properties, and boundary conditions) and solve systems of equations that govern the physics being modeled—whether structural, fluid, thermal, or electromagnetic. Different solvers are optimized for specific types of problems, such as implicit solvers for static structural analysis or explicit solvers for high-speed dynamic events. In multiphysics simulations, solvers may work sequentially (weak coupling) or simultaneously (strong coupling) to resolve interactions between different physical domains. Advanced solvers leverage parallel computing and iterative algorithms to improve accuracy and reduce simulation time.  

Let us see how higher computing power benefits multiphysics simulation software in solving complex physics problems associated with intricate systems:

Model Resolution and Mesh Refinement  
Higher computing power allows for finer meshes, which are critical in capturing complex physics interactions. In aerospace, for instance, simulating hypersonic aerothermodynamics requires resolving thin boundary layers, shock waves, and thermal gradients. Industry standard CFD solvers use adaptive meshing to refine regions with high thermal or aerodynamic loads, ensuring accurate heat transfer predictions. Similarly, for ship hydro-elasticity, CFD and FEA solvers can model fluid-structure interaction with high-resolution meshes, capturing wave impacts and hull deformations more precisely. Without sufficient computing power, such simulations would either be too coarse or computationally prohibitive.  

Solver Efficiency and Parallel Computing  
Multiphysics problems often involve nonlinear, transient phenomena that require iterative solving. Solvers such as OptiStruct and Flux leverage parallel processing to distribute workloads across multiple CPU / GPU cores. For example, in pantograph-catenary interaction simulations, the electromagnetic-structural coupling must be solved in real-time as the train moves. High-performance computing (HPC) clusters further accelerate these computations, making large-scale simulations feasible.  

Advanced Coupling Methods  
Multiphysics problems can be solved using one-way (sequential) or two-way (iterative) coupling. Strong coupling (where both physics affect each other simultaneously) is computationally expensive but more accurate. Platforms like HyperWorks facilitate tightly coupled simulations, such as in hypersonic vehicle analysis, where aerodynamics and thermal-structural responses are solved together. Increased computing power allows for faster data exchange and convergence, making such simulations practical for industrial applications.  

Real-Time and Post-Processing Capabilities  
Modern computing enables faster visualization and post-processing, which is crucial for interpreting multiphysics results. They allow engineers to analyze large datasets from coupled simulations efficiently. For instance, in railway pantograph-catenary simulations, engineers need to assess contact forces, vibration frequencies, and current collection stability. High-performance computing allows for real-time visualization of these interactions, helping optimize designs before physical testing.  

Industry leaders like Altair are leveraging the enhanced computing capabilities to provide sophisticated simulation solutions. Altair’s SimLab is a process-oriented, multidisciplinary simulation platform designed for accurate analysis of complex assemblies using multiphysics workflows. The platform supports seamless integration with popular CAD tools and offers automation features such as feature recognition, design of experiments, and optimization templates. This allows engineers to efficiently explore design variants, optimize performance, and ensure reliability across multiple physical domains

The Role of Design Companies in Multiphysics Simulation
Design companies play a pivotal role in multiphysics simulation by bridging the gap between theoretical modelling and real-world engineering applications. They leverage advanced simulation tools, such as Altair’s HyperWorks suite, to optimize product performance, reduce development costs, and accelerate time-to-market. By integrating multiphysics analyses early in the design process, they can predict complex interactions—such as thermal stresses in aerospace components, fluid-structure dynamics in ship hulls, or electromagnetic-mechanical behaviour in railway systems—before physical prototyping. Additionally, design companies often collaborate with software providers to customize simulation workflows, ensuring accuracy and efficiency for industry-specific challenges. Their expertise in interpreting simulation results allows them to make data-driven design improvements, enhancing reliability and safety. Furthermore, as industries push toward sustainability and lightweighting, design firms use multiphysics simulations to explore innovative materials and configurations, ensuring compliance with regulatory standards while maximizing performance. Ultimately, their role is critical in transforming computational insights into practical, manufacturable solutions.  

To conclude, multiphysics simulation is crucial for solving real-world engineering problems where multiple physical phenomena interact. The increasing power of modern computers has revolutionized multiphysics simulation by enabling higher-resolution models, faster solvers, advanced coupling techniques, and efficient post-processing. Product design companies bridge the gap between theory and practical applications of multiphysics for complex systems.