Engine Bay

Engine Encapsulations and Engine Covers

Innovative engine encapsulations help to store heat in the engine bay for longer periods so that less fuel is used for cold starts, thereby reducing vehicles’ emissions. They also minimize the engine noise emitted to the interior and the exterior of the vehicle.

Autoneum is a pioneer in the development of engine encapsulations and offers a key technology here with Theta-FiberCell. Theta-FiberCell is a lightweight fiber-foam-material and is mounted directly onto the engine or vehicle. In addition to its noise reduction and thermal insulation properties and associated high temperature stability up to 200°C, Theta-FiberCell is barely inflammable and highly resistant to engine vibrations.

The pioneering Theta-FiberCell technology is also used for the development and manufacture of engine top covers. These products are mounted onto the vehicle where they partially or fully cover the engine. Conventional covers are made of plastic and provide a screen for individual components of the engine for aesthetic reasons. By comparison, engine covers based on Theta-FiberCell are not only lightweight but also multifunctional: They reduce engine noise inside and outside cars and provide heat protection.

Autoneum Offers the Following Products for Application in the Engine Bay:

  • Engine Encapsulations
  • Hoodliners
  • Outer dashes and other body-mounted absorbers
  • Engine top covers
  • Battery covers
  • Fender insulators
  • Water box shields

Hybrid-Acoustics PET
Sustainable noise protection in the engine bay

With Hybrid-Acoustics PET, Autoneum has adapted its textile interior technology Hybrid-Acoustics for use in the engine compartment. The patented innovation is based on a unique fiber material that acts as an insulator and absorber at the same time. Among others, Hybrid-Acoustics PET is used to encapsulate electric motors, thereby reducing noise directly at the source and particularly attenuating high-frequency sounds of the electric drive unit. This key technology accordingly ensures optimum noise protection in the passenger cabin and greater driving comfort.

At the same time, components made of Hybrid-Acoustics PET convince with their low weight. Compared to conventional insulators, they are up to 40 percent lighter and thereby contributing to a greater driving range. They are also flameproof and find application as powertrain-mounted insulators for combustion engines thanks to their temperature resistance of up to 180°C.

The parts, which consist to a large extent of recycled PET fibers, are produced waste-free and are completely recyclable – an outstanding life cycle assessment compared to equivalent components in the engine bay.

Key Technology for Engine Encapsulations

Innovative engine encapsulations enhance the efficiency and sustainability of vehicles: The heat storage in the engine bay achieved with the encapsulations reduces fuel consumption at the next cold start, which in turn leads to lower vehicle emissions.

Autoneum recognized the growing importance and far-reaching potential of the thermo-acoustic insulation of vehicles at an early stage and has developed an innovative material:
Theta-FiberCell combines the benefits of the fiber absorber Theta-Fiber and foam absorber Theta-Cell. Theta-FiberCell, the key technology for engine encapsulations launched on the market in 2012 is based on Autoneum’s long-standing experience and takes into account customer-specific product requirements such as optimum noise protection and integrated thermal insulation. The high temperature stability entailed by this thermal insulation is also of major importance for vehicle manufacturers: Theta-FiberCell is barely flammable and can withstand temperatures of up to 200°C.

Theta-FiberCell also appeals due to its lightweight and displays high resistance towards engine vibrations. Theta-FiberCell can be used for engine encapsulations mounted onto the engine or vehicle.

As well as the acoustic absorption of interior (by up to four decibel) and exterior (by up to eight decibel) noise, the fiber-foam solution enables heat to be stored for long periods after the vehicle has been parked. After being switched off for 12 hours, the temperature of an engine with Theta-FiberCell encapsulation is six degrees higher than one without this special insulation.

This difference in temperature results in a higher engine oil temperature and less internal friction of the engine which in turn enhances the efficiency and sustainability of vehicles. Each six degrees increase in engine oil temperature reduces CO2 emissions by three grams per kilometer driven.

Multifunctional Non-Woven Technology

With Theta-Fiber, Autoneum offers a robust and multifunctional non-woven material for treatment in the engine bay. Up to 70 percent recycled fiber material is used for manufacturing components based on the semi-structural Theta-Fiber material technology.

Theta-Fiber stands out against conventional non-woven components above all thanks to its high temperature resistance: While traditional thermoplastic materials are able to withstand temperatures of up to 150°C, noise and thermal insulation parts based on Theta-Fiber can also be applied at temperatures of up to 200°C.

Compared to traditional heavy engine covers made of solid plastic, Theta-Fiber engine covers achieve weight savings of up to 60 percent, reduce the interior and exterior noise of vehicles and insulate heat generated by the engine.

Due to its high temperature stability, resistance to vibrations, lightweight, good acoustic properties and integrated thermal insulation, Theta-Fiber is a core element of Autoneum’s innovative engine encapsulations.

Durable and Lightweight Foam Components

Theta-Cell is an innovative polyurethane foam material developed by Autoneum. It is used for different applications such as lightweight and multifunctional hoodliners, outer dashes, tunnel insulators and battery covers. Compared with conventional acoustic absorbers, Theta-Cell components can be used to achieve weight reductions of up to 60 percent as well as high thermal insulation.

Products based on Theta-Cell are able to withstand temperatures of up to 180°C at peak; they meet customer requirements and legal provisions with regard to the non-flammability of components for the engine bay. They are also oil and water-repellent and help to reduce the interior and exterior noise of vehicles.

Theta-Cell combines with the felt material Theta-Fiber to form the substrate Theta-FiberCell that is used for the engine encapsulations provided by Autoneum.