Construction & calculation

For our engineering customers, we design products, components or complete systems that are designed from the outset to minimize mass or meet other target criteria while simultaneously fulfilling all requirements. The earlier certain target values are considered in product development, the less time and money is required for implementation. In this way, we enable our customers to develop and use innovative lightweight construction concepts with the support of TGM know-how without having to specially train their own designers.

Our approach always depends on the product, but is based on the consulting scheme of first optimizing the system, then the structure and finally the material. As with our Lightweight construction consulting we analyze the current status at the start of the project. The starting point can be an idea, a graphic, an initial design or a current product. Following the analysis, we develop one or more concepts as to how the product can be upgraded. Different variants show different solutions, which we evaluate for and with our customer. Thanks to our wide-ranging engineering knowledge and with the help of our cooperation partners, we can also consider the topics of design, material, production and costs in addition to the criterion of weight.

We support product development from the very early pre-development phase to the advanced concept phase with various tools and methods.

We offer exclusive CAD concept development in conjunction with FEM-based structural analysis to quickly generate different solution variants for our customers that quickly converge within the specified target corridor.

CAD concept development is typically carried out in the early phases of the product development process and is an important step in the design of components, assemblies or complete systems.

During CAD concept development, various ideas and concepts are created and tested in the form of digital models. This makes it possible to evaluate and compare different design options quickly and cost-effectively in order to identify the best design.

CAD concept development can also help to identify errors and problems in the design before the physical prototype is built, which can save time and money.

CAD concept development usually comprises various steps, such as the creation of sketches, the creation of 2D and 3D models, the preliminary analysis of loads and forces as well as the simulation of movements and material evaluation, whereby we offer our customers the following tools and working methods:

Cloud-based CAD software: One of the latest developments in CAD concept development is the availability of cloud-based CAD software solutions. These allow users to access and edit their CAD models from anywhere in the world without having to perform a local software installation.
Concept development for additive manufacturing (3D printing): 3D printing is increasingly being used in CAD concept development to create prototypes and models more quickly and cost-effectively. The use of 3D printers allows users to test and revise their models quickly and easily, which can speed up the design process.

We offer professional support in the field of CAD concept development in the

Automotive/commercial vehicle/rail vehicle construction from

Body-in-white and car body assemblies made of formed sheet metal parts, cast components as well as extruded profiles and extruded components paired with expert knowledge in the industrialization of highly complex welded constructions in a wide variety of steel and aluminium alloys
Interior and exterior trim parts, seating systems, air conditioning systems and ducts as well as various other interior and exterior add-on parts made of metallic, plastic-based and hybrid materials

Automotive/commercial vehicle construction

Architecture and packaging of internal combustion engine, hybridized and electrically powered vehicles including in-depth assessment of driving dynamics and comfort driving characteristics
Kinematic design of transmission systems or joint mechanisms
Rigid kinematic design and assessment of chassis components to achieve driving dynamics and comfort-determining properties, including in-depth knowledge of spring/damper and steering design and elastokinematic assessment skills
Conceptual design and analysis of the operating mechanism of brakes and tires
Preliminary and conceptual design of crash structures including in-depth understanding of the structural design and behavior of vehicle structures to meet consumer protection and legal requirements

Aircraft construction

Airframe structures including primary fuselage and wing structures as well as cladding made of plastic composites (CFRP/GRP) including engine cowlings and mounts
Primary structures, secondary structures, aircraft systems including electrical and avionics installations as well as interior linings, cabins, seats and aircraft doors.
Mockups, test rigs

Shipbuilding

Deck superstructures, cabins and add-on parts as well as interior linings and seating systems

EDP :

Catia V5
Onshape

Structural analysis and calculation

In automotive and commercial vehicle construction we offer

The investigation of structural integrity and the identification of sustainable structural and material lightweight design potential, as well as material modelling and the identification of structural and material lightweight design potential based on linear and non-linear FEM simulations and multi-parameter optimization calculations of automotive components and systems. This can be done both at the level of the entire vehicle and at the level of components such as body parts, frames, wheel suspensions, steering systems, brakes, engines and gearboxes as well as other add-on parts.

We support all aspects of linear and non-linear strength calculations, structural optimization, stiffness analyses, fatigue strength analyses, material modeling and selection, impact and crash simulations and the associated multi-physical parameter analyses. The aim of these analysis methods is to improve the safety, performance, efficiency and durability of automotive components and systems.

During structural analysis, simulations are carried out to determine how a particular component or system will react to various loads such as dynamic and static forces, vibrations, temperature and environmental conditions. The results of these tests and simulations are used to optimize the design for mass, for example, and to select the right materials to ensure minimum mass with maximum strength, stiffness and fatigue resistance.

As part of crash simulations, we investigate the behavior of the vehicle in the event of an accident. This involves investigating how the various components and systems of the vehicle react to a collision and how the safety of the occupants can be improved.

In rail vehicle construction we offer

the investigation of the structural integrity of rail vehicle components and systems as well as material modelling and the identification of sustainable structural and material lightweight design potentials on the basis of linear and non-linear FEM simulations and multi-parameter optimization calculations. This can take place both at the level of the entire vehicle and at the level of the components:

Body shell and bogies: form the structural basis of the rail vehicle and must therefore be sufficiently rigid and durable to withstand the static and dynamic loads of operation for up to 30 years as well as crash loads.
Vehicle interior and exterior: The body and bodywork of a rail vehicle are important components that ensure that the vehicle is aerodynamic, safe, ergonomic and has an aesthetic appearance. Occupant protection plays a major role here.
Windows and glazing: The windows and glazing of a rail vehicle must be safe and meet the requirements for transparency, safety and sound insulation.
Passenger compartment doors, driver's doors and flaps: Doors and flaps are important components that allow passengers to access the rail vehicle. They must be safe, fire-resistant, easy and quick to open and close and withstand the static and dynamic operating requirements.
Seating systems: The seating systems of a rail vehicle must be comfortable, safe, fire-resistant and ergonomic, as well as enabling smooth operation.
Electrical and electronic systems: Electrical and electronic systems are important components of a rail vehicle that are responsible for controlling and monitoring the vehicle and for communicating with the train crew and the rail network.
Wheels, axles and the braking system: The wheels and brakes of a rail vehicle must meet very high safety and functional requirements and be able to withstand static and highly dynamic operating loads, including peak and vibration loads, for over 30 years.

In aircraft and spacecraft construction we offer

the investigation of the structural integrity of aircraft components and systems as well as material modeling and the identification of sustainable structural and material lightweight design potentials on the basis of linear and non-linear FEM simulations and multi-parameter optimization calculations. This can take place both at the level of the overall system and at the level of the components:

Fuselage: The fuselage is the main structure of the aircraft and includes the passenger cabin, the cargo compartment and the fuel tanks. The fuselage structure is analyzed to ensure that it can withstand the aerodynamic loads, cabin pressure and numerous flight load cases.

Wings: The wings are subject to very high dynamic and static loads and must have an aeroelastic design. They are examined for their structural strength, stiffness and fatigue strength, vibration properties and aeroelastic behavior.

Tail unit: The tail unit comprises the horizontal stabilizer and the vertical stabilizer. It is examined for structural integrity, stability and controllability to ensure safe control of the aircraft even under the most adverse operating conditions.

Landing gear: The landing gear includes the main landing gear and nose wheel. It is tested for structural strength and durability based on numerous landing gear load cases to enable safe landing and taxiing on the ground.

Engines: The engines, whether electric or internal combustion engine-driven turbine or piston engines, are also structurally analyzed to ensure that they can withstand the forces and vibrations during operation at a high safety level and have the lowest possible energy consumption.

In shipbuilding we offer

Structural analysis and structural optimization of ship components and systems. Structural analysis is used to determine the loads and stresses on the ship's structure in order to ensure its strength, rigidity and stability.

Optimization is concerned with improving structural efficiency in order to reduce the weight and cost of the ship and improve sustainability without compromising the required strength and rigidity. Various factors are taken into account, such as the choice of materials, the design of the hull shape, the placement of reinforcements and the optimization of welded joints.

By using special analysis and optimization techniques, shipbuilders can improve the performance, sustainability, safety and efficiency of their ships. This makes it possible to both meet customer requirements and counteract the environmental impact and operating costs. Ultimately, structural analysis and optimization help to develop innovative and competitive ship designs.

During the structural examination of a ship, various components and areas are typically taken into account. These include:

Hull: The hull is the main structure of the ship and is analyzed for strength, rigidity and stability. In particular, the longitudinal beams, frames, bulkheads and planking are examined.

Decks and superstructures: The decks and superstructures, such as bridges, superstructures for passengers or cargo holds, are checked for their load-bearing capacity and structural integrity.

Connecting elements: Connecting elements such as weld seams, rivets or screws, which hold various structural elements together, are tested for strength and reliability.

Support structures: Special support structures such as crane foundations, bulkheads or suspensions for drive systems are examined to ensure that they can withstand the required loads.

Ballast systems: Ballast tanks or systems are tested for their integrity and their ability to absorb ballast water or compensate for weight shifts.

Bulkheads and doors: Bulkheads (partitions) and doors that separate the different areas of the ship from each other are examined for their tightness and structural integrity.

Structural loads: Investigations also include the analysis of structural reactions to various loads such as wave impact, swell, forces during mooring or rolling.

The structural analysis covers various aspects of the vessel to ensure that it meets the requirements for strength, rigidity, safety, sustainability, durability and operability.

Calculation skills

Static verification calculation

The static strength verification is the standard FEM calculation. The aim here is to verify the load-bearing capacity (strength) for an acting load or a load spectrum. Depending on the complexity of the design and the boundary conditions (bearing, loads, material), we carry out a linear or a non-linear FEM calculation. In many cases, a linear FEM calculation, which involves a higher level of abstraction, is sufficient for both technical and economic reasons.

However, if large loads or extreme lightweight construction pushes the limits of the load-bearing capacity, the non-linear FEM calculation is the best option. Then either plasticization occurs due to exceeding the yield point (material non-linearity) or the static equilibrium is endangered by large deformations (geometric non-linearity), e.g. due to buckling or buckling. In these cases, only the non-linear calculation is meaningful. This also applies if contacts are not to be ideally mapped. Material non-linearity can also be caused by the material used; this is (often) the case with plastics, magnesium, composites and sandwich structures. It can also be supplemented by a screw calculation in accordance with VDI2230.

Our service does not end with the handover of the graphically processed stresses and strains. If required, we can interpret the results for our customers and identify lightweight construction potential. In order to be able to calculate exact results, we use our customers' material data or material cards of common materials from our FEM tool. We also accept characteristic values supplied by the customer. To determine unknown material parameters, we recommend competent partners from our network.

Service life calculation

One analytical method for assessing the service life of a component is to determine its fatigue strength. The fatigue strength tests do not include the investigation of damage caused by special events, as in the case of shock tests. Rather, they deal with damage caused by everyday long-term stresses in the material by means of vibrations. The static tensile test can be used to determine the stress value at which a sample begins to deform plastically and ultimately crack. In the case of metal, this point is determined by the tensile strength of a material.

In dynamic tensile tests, on the other hand, failure can occur at stresses far below the tensile strength. This phenomenon can be described using a Wöhler test. In order to be able to evaluate individual components for damage, the entire system is subjected to a prescribed vibration profile. In this way, the acceleration loads of several hundred thousand kilometers driven in the everyday life of a car can be simulated on a shaker in just a few hours. Using the measurement data from the endurance test and the Wöhler curve created in advance as a basis, various software packages can be used to decide, based on the principle of linear damage accumulation, whether stresses occur at connection points or in the material that lead to failure of the structure.

The term fatigue strength implies the behavior that a component could withstand an infinite number of cycles under corresponding loads without ever cracking. In reality, however, this can only be realized with very high safety margins, which would make many lightweight construction concepts unfeasible. The fatigue strength values are therefore multiplied by corresponding reduction factors in order to be able to design a component to be operationally stable for a reasonable period of time without having to calculate unnecessarily high material costs and quantities. Each damage value is therefore always accompanied by a service life value, which is a measure of the service life of the structure under investigation.

Crash calculation

Crash calculation is a form of FEM calculation. Here, individual or multiple bodies are examined for crash behavior. Various objectives can be pursued. For example, it is possible to determine the deceleration behavior of bodies or to investigate the behavior of the body in the event of failure.

Depending on the size and complexity of the bodies and the scope of the test methods, the calculation effort can be determined. Among other things, the size and number of elements is decisive for the calculation time. The crash calculation provides information on how a component/body behaves under the crash load. With these findings, the tested bodies can be designed more precisely for the load case in terms of topology optimization. A variation of the body with different materials can also be implemented as long as the corresponding material parameters are available.

Standards and reference values from the industry are used to design the test methods. The test methods differ depending on the industry; for the automotive industry alone, more than ten different tests are required to meet the requirements. Our services include the networking and testing of the bodies according to the required test methods. In addition, the results can be used to revise the existing body to improve the crash behavior while maintaining the same weight, or to reduce the weight while maintaining the same crash behavior. In order to be able to calculate exact results, we are also dependent on precise material parameters.

Material modeling

Material modeling is the process of mathematically and physically describing the behaviour of materials under different load conditions. It involves the development of mathematical models and equations that describe the behavior of the material and enable predictions to be made about its mechanical, thermal or other physical properties embedded in FEM simulations.

The aim is to understand the behavior of materials under different loads in order to be able to predict the performance of components or structures.

In material modelling, experimental data is used to characterize the material behaviour. Typically, different material parameters are identified and determined to represent the behavior of the material in the models. There are different types of material models developed for different material types and loading modes, such as linear elastic models, plastic models, viscoelastic models, viscoplastic models, damage models and many others.

CFD / aerodynamic simulation of climate systems

FEM analysis and modeling of the airflow and thermal conditions in an air conditioning system. These simulations are used to understand the behavior of the airflow, optimize the performance of the system and evaluate the impact on comfort and energy efficiency.

In the aerodynamic simulation of an air conditioning system, mathematical models and numerical methods are used to analyze the flow of air, heat transfer and other relevant physical phenomena in an air conditioning system. This typically includes

Geometry modeling: the air conditioning system and its components such as ventilation ducts, nozzles, heat exchangers and air outlet grilles are represented in a virtual model that represents the actual geometry and dimensions of the system.

Flow simulation: by solving the Navier-Stokes equations, which describe the movement of air, simulations can be carried out to predict the air flow in different operating conditions and configurations of the air conditioning system. This includes the analysis of pressure distributions, flow velocities, vortex formation and flow losses.

Heat transfer simulation: in addition to the flow simulation, the heat transfer effects in the air conditioning system are also taken into account in order to analyze the distribution of temperatures and the thermal performance of the components. This includes the consideration of heat conduction, convection and radiation.

Evaluation of performance indicators: aerodynamic simulation can be used to evaluate various performance indicators of the air conditioning system, such as the distribution of air velocities, temperature distribution, pressure loss, air distribution in the interior and heat transfer efficiency.

CFD / aerodynamic simulation of vehicle encounters

This type of simulation makes it possible to understand the interactions of the air flow between the vehicles and to evaluate their influence on vehicle performance.

In the aerodynamic simulation of vehicle encounters, mathematical models and FEM simulation methods are used to analyze the flow dynamics, the pressure curve and the forces that occur when vehicles approach and pass. This typically includes the following aspects:

Geometry modeling: the vehicle geometries are displayed in a virtual model that represents the actual shape and dimensions of the vehicles. This makes it possible to simulate the flow around the vehicles.
Flow simulation: by solving the Navier-Stokes equations, which describe the flow of air, simulations can be carried out to analyze the aerodynamic effects during vehicle encounters. This includes the calculation of the air flow, the pressure curve, the vortex formation and the flow turbulence.
Forces and drag analysis: the simulation allows the aerodynamic forces acting on the vehicles to be analyzed and the drag and lift during the encounters to be evaluated. This can provide important information to evaluate the stability, driving behavior and energy consumption of the vehicles.
Optimization: aerodynamic simulation of vehicle encounters can also be used to optimize vehicle geometry, air guiding elements and other aerodynamic properties to reduce drag and energy consumption.

CFD / thermal simulation of heat exchangers

Heat exchanger simulation refers to the process of modeling and analyzing heat transfer devices or components that are used to transfer heat from one fluid to another.

In the simulation of heat exchangers, numerical methods and models are used to understand the behavior of the heat transfer process, evaluate the performance of the heat exchanger and analyze different operating conditions. Typically, the simulation of heat exchangers includes the following aspects:
Flow simulation: the flow of fluids flowing through the heat exchanger is modeled and analyzed. This includes the calculation of flow velocities, pressure distributions and vortex formation within the heat exchanger.
Heat transfer simulation: the heat transfer between the fluids in the heat exchanger is modeled in order to evaluate the thermal performance. This includes the calculation of temperature distributions, heat conduction and convection processes.
Material behavior: the simulation can also take into account the behavior of the materials that make up the heat exchanger to evaluate heat transfer efficiency and the effects of thermal expansion, wear or corrosion.
Optimization: by simulating heat exchangers, different configurations, geometries or operating parameters can be analyzed to optimize the performance and efficiency of the heat exchanger.

Methodical optimization

Analysis of influencing variables

The requirements for a component change over time. This can happen within a product development process, but also over several product generations. Due to the high pressure to reduce development times and the frequent separation between responsibility for requirements and development/design, it often happens that requirements are not questioned. An understanding of the relationships and influences between several components is also lost if the areas of responsibility are strictly separated.

We take a step back and analyze the relationships, dependencies and influences of a system or component. The result, visualized in a diagram, helps to understand interrelationships. This is the only way to uncover weak points and identify potential, both primary and secondary. Our customer can then take targeted measures to reduce weights and/or costs.

Structural optimization

For structural optimization in a lightweight design consulting process, the product is structurally optimized using finite element analysis programs in a calculation process. Suitable calculation methods are selected based on the product requirements. After structural optimization, the product should continue to fully meet all technical requirements.

Topology optimization

By visualizing the load paths, the component to be optimized can be developed with minimum material usage, i.e. minimum weight, with the greatest possible rigidity. The design thus follows the lightweight construction principle "use material only where it makes sense".

The appropriate parameter settings, referred to here as restrictions and optimization targets, ensure that the result meets the customer's requirements. For example, manufacturing processes, symmetries, min/max wall thicknesses and safety values to be achieved can be defined. Following topology optimization, a transfer to a CAD design is possible. This can be used to carry out a static strength analysis, obtain quotations from manufacturers or create a sample in the 3D printer.

Topography optimization

Similar to topology optimization, topography optimization offers the possibility of optimizing the natural frequency and/or stiffness. While topology optimization focuses on thick-walled components (e.g. milled or cast components), topography optimization is used to optimize thin-walled or shell-shaped components (e.g. formed sheet metal parts). For minimum weight or maximum rigidity, shell-shaped components are stiffened by beading, i.e. by introducing elevations or depressions perpendicular to the surface. Topography optimization helps to find the perfect bead pattern. Parameter settings are used to take manufacturability into account. Following topography optimization, a transfer to a CAD design is recommended. This can be used to carry out a static strength verification, obtain quotations from manufacturers or create a sample in the 3D printer.

Size optimization / size optimization

This method optimizes the dimensions of a component to achieve specific performance targets such as strength or stiffness. Geometric parameters can also be varied to improve performance.

Shape optimization

In shape optimization, the surface geometry and profile shape of a component are optimized in order to achieve certain structural-mechanical goals.

Parameter optimization

This method optimizes numerical parameters that are used in mathematical models or simulations to find the best values for certain target variables.

System optimization

In addition to the evaluation of the system and the existing structures, lightweight material construction is also used. In addition, we pay particular attention to the combination and integration of functions via lightweight system design, as well as the special consideration of component interfaces and the consideration of "snowball effects", which describes the mutual feedback between the lightweight construction measures. The holistic approach is also reflected here, as the weight savings can be directly reflected in both the specifications and the weight book, creating new potential in other assemblies.

Modal analysis

In modal analysis, the natural frequency and natural vibration modes of a component are determined, which are used to design dynamically loaded structures.
The analysis can be performed on unstressed, restrained and prestressed as well as undamped and damped systems. In addition, the determination of the natural frequency helps in the assessment of structural optimization measures. An equal or higher natural frequency with a lower mass can be used as an indicator of successful (weight) optimization. This simplification can be made if the verification of the overall system is time-consuming or costly.

Frequency response analysis

Perform an analysis to identify potentially dangerous frequencies of the design and compare them with the external vibration pattern. The aim of this analysis is to predict and prevent the system or component under investigation from operating at resonant frequencies. This mode of operation can lead to failures due to mechanical damage.