Sound Channeling Material? Polymer or Other?

In summary, a car manufacturer is looking to enhance the "Feel & Experience" of driving their cars by improving the sound and acoustic feeling when accelerating. They have asked for a conceptual design that does not use the exhaust or artificial equipment. The person designing the concept is considering creating a cover for the engine to manipulate and channel the sound towards the cabin. They are looking for materials and technology to assist with this project and have received suggestions such as using a parabolic collector and harmonic oscillator. However, it may be difficult to achieve this without changing the engine itself. Alternatively, a hole could be drilled to allow sound from the engine to enter the cabin, but this could lead to engine fluids entering the car.
  • #1
topgear17
8
0
Hey Guys,

Been a while since my last visit, as I've been away for a well earnt break..

But recently I've been set a challenge and its baffling me some what, and i wonder if anyone can help pleaseeee:biggrin:


Basically long and short of it, a Car Manufacturer has been struggling in enhance the "Feel & Experience" of driving there cars, customers have mentioned they'd like more sound and acoustic feeling when accelerating.

Now I've been asked to design a conceptual to that enhances the sound characteristics of the engine, NOT USING the exhaust... and NOT USING ARTIFICIAL EQUIPMENT..(Basically Aston Martin and a few other manufacturers actually use small microphones placed in the engine bay and after a certain rev band is accessed, play those noises under the dashboard to enhance the drivers experience..

So am thinking of making some sort of cover for the engine to manipulate and channel the sound of the engines tones towards the cabin..

Anybody know of any materials that's properties would assist me?
Or any technology you may suggest i look into to help me as am relatively stumped...


Thanks
T.
 
Engineering news on Phys.org
  • #2
I don't think they are avaliable commercially.
 
  • #3
Many materials conduct sound well enough. The true challenges are
- Avoid lengthy reflections at the channel's ends
- Control all propagation modes to avoid metallic sound
- Pass the sound efficiently from air to solid to air, typically with a membrane.
 
  • #4
topgear17 said:
Hey Guys,

Been a while since my last visit, as I've been away for a well earnt break..

But recently I've been set a challenge and its baffling me some what, and i wonder if anyone can help pleaseeee:biggrin:Basically long and short of it, a Car Manufacturer has been struggling in enhance the "Feel & Experience" of driving there cars, customers have mentioned they'd like more sound and acoustic feeling when accelerating.

Now I've been asked to design a conceptual to that enhances the sound characteristics of the engine, NOT USING the exhaust... and NOT USING ARTIFICIAL EQUIPMENT..(Basically Aston Martin and a few other manufacturers actually use small microphones placed in the engine bay and after a certain rev band is accessed, play those noises under the dashboard to enhance the drivers experience..

So am thinking of making some sort of cover for the engine to manipulate and channel the sound of the engines tones towards the cabin..

Anybody know of any materials that's properties would assist me?
Or any technology you may suggest i look into to help me as am relatively stumped...Thanks
T.

Assume you want this to be 100% passive.

Imagine an auditorium (in fact read about auditorium design). Geometry is going to be the factor for optimal focusing. Then you want to design whatever you do to have a resonance frequency near the Frequency of sound of the engine so it reverbs with the sound thus magnifying it.

So the project has two parts.
1. directing the sound - some sort of casing / funnel design potentially, maybe some sort of parabolic or semi-parabolic focuser
2. amplifying the sound - some for of harmonic oscillator with resonance near the tone you want to amplify (probably the deep rev).

hm ... I'm imagining a parabolic collector near the engine that focuses onto a harmonic oscillator near the resonance frequency of the tone that is in a partial parabolic dish focused towards the driver with focal point near the drivers head.
 
Last edited:
  • #5
ChaseRLewis73 said:
Assume you want this to be 100% passive.

Imagine an auditorium (in fact read about auditorium design). Geometry is going to be the factor for optimal focusing. Then you want to design whatever you do to have a resonance frequency near the Frequency of sound of the engine so it reverbs with the sound thus magnifying it.

So the project has two parts.
1. directing the sound - some sort of casing / funnel design potentially, maybe some sort of parabolic or semi-parabolic focuser
2. amplifying the sound - some for of harmonic oscillator with resonance near the tone you want to amplify (probably the deep rev).

hm ... I'm imagining a parabolic collector near the engine that focuses onto a harmonic oscillator near the resonance frequency of the tone that is in a partial parabolic dish focused towards the driver with focal point near the drivers head.

The sound of an engine is not a single frequency but rather a noise (although there might be a predominant one), so that you would need a number of oscillators.
 
  • #6
topgear17 said:
Hey Guys,

Been a while since my last visit, as I've been away for a well earnt break..

But recently I've been set a challenge and its baffling me some what, and i wonder if anyone can help pleaseeee:biggrin:


Basically long and short of it, a Car Manufacturer has been struggling in enhance the "Feel & Experience" of driving there cars, customers have mentioned they'd like more sound and acoustic feeling when accelerating.

Now I've been asked to design a conceptual to that enhances the sound characteristics of the engine, NOT USING the exhaust... and NOT USING ARTIFICIAL EQUIPMENT..(Basically Aston Martin and a few other manufacturers actually use small microphones placed in the engine bay and after a certain rev band is accessed, play those noises under the dashboard to enhance the drivers experience..

So am thinking of making some sort of cover for the engine to manipulate and channel the sound of the engines tones towards the cabin..

Anybody know of any materials that's properties would assist me?
Or any technology you may suggest i look into to help me as am relatively stumped...


Thanks
T.

I give you my car for one of yours, mine makes too much noise for my taste. In my case the reason is in the engine rather than in the materials the rest of the car is made of. This particular engine operates at higher revolutions than other engines do. If you can't change your engine, then you can not do much more than drill a hole to communicate the interior of the car with the underhood space. But, if you don't like having engine fluids getting around you then you can close the hole with a membrane, as if it were a drum.
 
  • #7
Getting engine sound into the passenger compartment is as easy as removing acoustic insulation. The real issue here I think is getting the engine sound in while excluding road noise and other undesirable sound.

You might explore the idea of skipping the air phase of the sound conduction from the engine to your channeling device. Why not collect the sound directly from the engine block. The engine is going to be supported by several engine mounts. Usually these mounts are attached to sub-frame but suppose 1 mount were attached to the firewall, Voilà, engine sound is transferred to the firewall in proportion to the hardness of the rubber used in the mount and there is very little effect on other sound insulation. If you wanted to get fancy about it you could use a hydraulic mount with magnetorheological fluid so that a module could control sound transfer rates.
 
  • #8
Guys thanks for your input some great stuff here...

Right let me respond to some of the replies :)
Assume you want this to be 100% passive.

Imagine an auditorium (in fact read about auditorium design). Geometry is going to be the factor for optimal focusing. Then you want to design whatever you do to have a resonance frequency near the Frequency of sound of the engine so it reverbs with the sound thus magnifying it.

So the project has two parts.
1. directing the sound - some sort of casing / funnel design potentially, maybe some sort of parabolic or semi-parabolic focuser
2. amplifying the sound - some for of harmonic oscillator with resonance near the tone you want to amplify (probably the deep rev).

hm ... I'm imagining a parabolic collector near the engine that focuses onto a harmonic oscillator near the resonance frequency of the tone that is in a partial parabolic dish focused towards the driver with focal point near the drivers head.

Firstly yes directing the sound will be a vital part of this project, the focus will be majorly focused towards enhancing the drivers experience, when applying medium to full throttle... therefore the product would need to be almost silent when engines at low speed ( for arguments sake below 3,000 rpm) then be activated once a threshold has been breeched for example (3200rpm)
-I totally agree the 1 stage is going to be some sort of channeled casing.. the semi-parabolic focuser sounds very intriguing it is something i will certain look into with more detail..

Secondly - This is where i see the stumbling block, yea i am going to have to somehow isolate the frequency or frequencies that are let's say defined as desirable by drivers, and design a resonator system that amplifies those frequencies through some kind of diaphragm system focused towards the driver.



Since my post i have had a meeting with the manufacturers development department:
maybe this information can shed some light on things:

-Yes it has to be an engine cover so to speak, or an above engine piece that enhances the drivers experience.

-Preference is leaning towards, using mechanisms and sound manipulation (through resonator technology) rather than artificial means, speakers microphones etc etc...


Now i have researched a few other manufacturers have attempted similar systems: for example Audi /Volkswagon, had a system that using air flow from the air intake passing through a resonator chamber above the engine, vibrated a diaphragm to amplify the engine tone...

But this was apparently scraped after testing as it sounded more like a "woodpecker" pecking at the bulkhead...

Please bare in mind this is going to be used and tested on a V8 and possibly a V12 engine so please don't confuse the required engine tone, that of one from a small 4 four cylinder daily round around...

Thanks very much for your input guys, massively appreciated.

Thanks, any questions fire away
 

1. What is sound channeling material?

Sound channeling material, also known as acoustic material, is a type of material that is designed to absorb, reflect, or diffuse sound waves. It is commonly used in building construction, music studios, and other environments where sound quality is important.

2. How does sound channeling material work?

Sound channeling material works by altering the path of sound waves as they travel through the material. This can be achieved through various mechanisms such as absorption, reflection, and diffusion. The specific mechanism depends on the type of material used.

3. What types of materials are commonly used for sound channeling?

The most commonly used materials for sound channeling are polymers, such as foams or plastics, and other porous materials like wood or fabric. These materials have the ability to absorb and diffuse sound waves, making them ideal for sound control applications.

4. What are the benefits of using sound channeling material?

The main benefit of using sound channeling material is improved sound quality. By reducing echoes, reverberation, and outside noise, sound channeling material can create a more pleasant and controlled acoustic environment. It can also improve speech intelligibility and reduce stress on the ears.

5. How do I choose the right sound channeling material for my project?

The choice of sound channeling material depends on the specific needs of your project. Factors to consider include the type of sound control needed, the size and shape of the space, and the budget. It is best to consult with a professional acoustic engineer to determine the most suitable material for your project.

Similar threads

  • Mechanical Engineering
Replies
17
Views
1K
Replies
7
Views
2K
  • STEM Career Guidance
Replies
2
Views
1K
Replies
8
Views
2K
Replies
4
Views
8K
  • STEM Academic Advising
Replies
11
Views
2K
Replies
1
Views
724
  • Science and Math Textbooks
Replies
5
Views
3K
  • Materials and Chemical Engineering
Replies
5
Views
3K
Back
Top