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Common Gas Flow Resistivity numbers.
Old 5th August 2018
  #151
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Well, perhaps somebody will ask them directly. It is a lovely material.
They do have data on the website in terms of grammes per square metre.
My arithmetic is terrible so do check the number I got for Quietspace panel, 68Kg/m^3.

Let's remember it's cousin Caruso Isobond. 040 has a density of 20K, GFR of 5K.
035, bizarrely, has a density of 45K, GFR of 12K.

DD
Old 8th August 2018
  #152
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Quote:
Originally Posted by DanDan View Post
Well, perhaps somebody will ask them directly. It is a lovely material.
They do have data on the website in terms of grammes per square metre.
My arithmetic is terrible so do check the number I got for Quietspace panel, 68Kg/m^3.

Let's remember it's cousin Caruso Isobond. 040 has a density of 20K, GFR of 5K.
035, bizarrely, has a density of 45K, GFR of 12K.

DD
Why not just use the absorption coefficient Data tested? A lot of products have facings or density differences though the material. Using abs coeff is much more accurate for specific products.
Old 8th August 2018
  #153
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Quote:
Originally Posted by jazzkiwi View Post
Why not just use the absorption coefficient Data tested? A lot of products have facings or density differences though the material. Using abs coeff is much more accurate for specific products.
So I can properly plan the depth of the panel. Varying depths and angles of incident can change how effective a given material is.
Old 8th August 2018
  #154
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Quote:
Originally Posted by jazzkiwi View Post
Why not just use the absorption coefficient Data tested? A lot of products have facings or density differences though the material. Using abs coeff is much more accurate for specific products.
Low end response is fine but low mids are horroble. Why why why?

Absorbtion panels for early reflection
Old 19th August 2018
  #155
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Attached french results of an acoustic lab (CSTB) on Knauf products.
Can't find a newer version of this. this is from 2011.

I hope you can find your way thru with a few google translate copy / paste

here's some >
laine de roche = rockwool
laine de verre = glasswool
RÉSISTANCE À L'ÉCOULEMENT DE L'AIR = Air Flow Resistance
panneaux = panels
Rouleaux = rolls


Here are the tested products >>

Laine de roche TERMOFLOOR (épaisseur 30 mm)
Laine de roche TERMOBARDAGE (épaisseur 110 mm)
Laine de verre ULTRACOUSTIC SOFT (épaisseur 45 mm)
Laine de verre Facade 032 B (épaisseur 120 mm)
Laine de verre Facade 035 B (épaisseur 140 mm)
Laine de verre TP 416 (épaisseur 140 mm)
Laine de verre ACOUSTIQUEPLUS 032 (épaisseur 140 mm)
Laine de verre ACOUSTILAINE 035 (épaisseur 140 mm)
Laine de verre TI 312 (épaisseur 240 mm)
Laine de verre CLASSIC 035 (épaisseur 240 mm)
Attached Files
File Type: pdf KNAUF - absorptionacoustique.pdf (801.8 KB, 80 views)
Old 26th September 2018
  #156
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I bet this has been asked and discussed somewhere around this board BUT: why is the given flow resistivity of Homatherm Flex CL 43-76k Pa.s/m2?
All other porous materials have fixed values there.
Old 30th September 2018
  #157
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ABW's Natural Things and Stuff (De)

ABW Thermo Jute

thermal conductivity 0.0359 W / (m • K)
density 34-40 kg/m³
flow resistivity 3,4 kPa*s/m²

ABW Hemp

thermal conductivity 0.045 W / mK
density 50-60 kg / m³
flow resistivity 1,2 kPa s/m²
"Sound absorption at 6 cm thickness" a = 0,55 (H)


ABW Thermo Hemp Premium PLUS

thermal conductivity 0,040 W/(m·K)
density 30 - 42 kg/m³

ABW Thermo Hemp Premium

thermal conductivity 0,040 W/(m·K)
density approx. 38 kg/m³

Steico Flex Wood Fibre

thermal conductivity 0.039 W/(m·K)
density approx. 50kg / m³
flow resistivity ≥ 5 kPa s/m²


links:

Hanf - Dammwolle ST (Stopfhanf) fur Dach, Wand und Fassade
Thermo-Hanf Premium PLUS Mattenware per Paketdienst
Thermo-Hanf Premium Matten & Rollenware per Paketdienst
Thermo Natur Jute100 Matten & Rollenware per Paketdienst
Steico Flex Holzfaserdammung - Regional

Last edited by BurningRainbows; 30th September 2018 at 01:25 PM.. Reason: incorrect link given
Old 1st October 2018
  #158
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That is some very low flow resistivity numbers. Can someone with more knowledge than me (in both acoustics and German) clarify if the numbers are related to the thickness of the material or not?
Old 1st October 2018
  #159
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Quote:
Originally Posted by tlindaas View Post
the numbers are related to the thickness of the material or not?
If you ask if GFR (expressed in m²) changes with thickness. Simple answer is nope.

More on this here:

Acoustic Absorption in Porous Materials NASA/TM—2011-216995
https://ntrs.nasa.gov/archive/nasa/c...0110011143.pdf

"The specific flow resistance is one of the properties that determines both the sound absorbing and sound transmitting properties of a material. It measures how easily air can enter a porous structure, as well as the resistance that flow meets within the structure. Flow resistivity is independent of the area or thickness of the tested material."
Old 20th March 2019
  #160
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Isover was nice enough to provide these figures:

KL-31: 30 kPa*s/m2
KL-32: 24 kPa*s/m2
KL-33: 18 kPa*s/m2
KL-36: 9kPa*s/m2
KL-37: 9kPa*s/m2

Old 8th May 2019
  #161
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a few numbers i found for Termolan:

Painel PN40 >10kpa.s/m²
Painel PN55 >15kpa.s/m²
Painel PN70 >20kpa.s/m²
Painel PN70F >20kpa.s/m²
Isole+ >10kpa.s/m²
MN230 > 5kpa.s/m² 25-30kg/m³
VF > 5kpa.s/m² 25-30kg/m³


hope that helps someone....

cheers
Old 9th May 2019
  #162
Hope I can contribute to this great thread, I'm not very experienced and happy to be corrected if I have made any mistakes. This is what I found in my search for good local insulation types, with a focus on materials for deep bass traps:

Hunton Nativo wood fibre insulation seems very good for deep bass traps, the published figure is >=5 kPa/m2 and the density is 50 kg/m3. It is the most dense material I have found with low GFR available here in Norway so far. It is stocked by Montér.

At half the price but also half the density, Ursa Gul with a ~5 kPa/m2 GFR should be a great alternative. Stocked by Byggmax.

For less deep absorbers, Glava 38 økonomiplate looks like a good choice as it's almost as cheap as Ursa and judging by the data for "unspecified glass wool insulation" in the Norway thread its GFR should be around 10 kPa/m2 based on its density of 12 kg/m3. Maybe best to give them a call to make sure.
Old 1st August 2019
  #163
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I was searching for numbers for brazilian products and found some for portuguese Isover Ultimate by coincidence.
I don't know if this product is intersting for somone, but who knows. It is specialized (for ships) and has very elevated GFRs (that's why they compared the numers on the website): https://www.isover-isolamento-tecnic...mento-acustico

Resistência ao fluxo de ar (DIN EN 29053) kPa×s/m²
ULTIMATE
24 kg/m³: 15
36 kg/m³: 30
56 kg/m³: 50
66 kg/m³: 60
76 kg/m³: 80
86 kg/m³: 90
90 kg/m³: 100
Old 1st August 2019
  #164
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portuguese(?) Knauf:

GAMA ULTRACOUSTIC: 10 kPa·s/m2

ULTRACOUSTIC 7: 12 kPa·s/m2

https://pim.knaufinsulation.com/file...9c98d8cc46.pdf
Old 3rd August 2019
  #165
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any numbers for the PET stuff?
I was thinking here. since this material doesn't use glue the GFR should be pretty constant between the same density, no?

I can get a roll like this with 7 kg/m³ for pretty cheap here
Attached Thumbnails
Common Gas Flow Resistivity numbers.-1hk8dtdsimtc0w04wk.jpg  
Old 7th August 2019
  #166
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lots of values for "Fiberform 62" in this document: http://acustica.ing.unibo.it/Staff/massimo/apac2005.pdf

seams to be a swissproduct: https://www.vibraplast.ch/en/noise-c...-noise-control

what is intresting here is that they are far less air-resistive per kg than comparable Caruso Iso-bond products (to answer my own question above)

what is further intresting in this paper is that it suggests that airflow resistivity,acoustic impedance and sound absorption coefficient of polyester fibre materials can be predicted


and this paper shows the GFR/density curves for 3 diferent polyester fibre diameters in figure 5:
https://core.ac.uk/download/pdf/46563918.pdf

from what I understand, polyester is far more predictable since they only differ in fibre diameters and than how compressed they are. while mineral wool has far more variables

Last edited by capoeira; 7th August 2019 at 04:39 PM..
Old 7th August 2019
  #167
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Quote:
Originally Posted by capoeira View Post
lots of values for "Fiberform 62" in this document: http://acustica.ing.unibo.it/Staff/massimo/apac2005.pdf

seams to be a swissproduct: https://www.vibraplast.ch/en/noise-c...-noise-control

what is intresting here is that they are far less air-resistive per kg than comparable Caruso Iso-bond products (to answer my own question above)

what is further intresting in this paper is that it suggests that airflow resistivity,acoustic impedance and sound absorption coefficient of polyester fibre materials can be predicted


and this paper shows the GFR/density curves for 3 diferent polyester fibre diameters in figure 5:
https://core.ac.uk/download/pdf/46563918.pdf

from what I understand, polyester is far more predictable since they only differ in fibre diameters and than how compressed they are. while mineral wool has far more variables
Great stuff! Thank you.
Old 8th August 2019
  #168
Gear Maniac
 

Quote:
Originally Posted by capoeira View Post
any numbers for the PET stuff?
I was thinking here. since this material doesn't use glue the GFR should be pretty constant between the same density, no?

I can get a roll like this with 7 kg/m³ for pretty cheap here
Hello Capoeira... Fellow countryman!
In my limited experience PET wool is (much) more expensive than glass wool. Besides the tech benefit, it offers some advantages like being easy to deal with and be environmentally friendly.
Where do you find these cheaper in Brazil. I might be interested...
thanks!
Old 8th August 2019
  #169
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Quote:
Originally Posted by Mauricio Gargel View Post
Hello Capoeira... Fellow countryman!
In my limited experience PET wool is (much) more expensive than glass wool. Besides the tech benefit, it offers some advantages like being easy to deal with and be environmentally friendly.
Where do you find these cheaper in Brazil. I might be interested...
thanks!
HI. I am so happy to see your post. I am researching a lot these days.
I don't agree with the much more expensive part. we are kind of lucky here.
Here is an offer with prices on mineral wool level for example: https://www.vibrashop.com.br/la-de-p...12-pacote-p121
though I suspect this is 2000 Pa.s/m2 (or even lower) stuff.
I'm aming for 4000 or 5000 since the 2000 stuff would require the dubble amount of material at my aimed thickness to have the same effect: http://www.acousticmodelling.com/mli...&s42=1&d42=200

I found out we have 3 products available:

Fiberblock: which is probably the Vibrasom stuff and is dificult to find data (found only one graph which Vibrasom told me it is for the 50mm/30kgm3 stuff)

Isosoft from Trisoft: they have a PDF with some data, tests more focused on drywall aplication, though

Ecofibre: I have a nice PDF with 8 "laudos"


I'm atm trying to find out which (if) of the last two is close to Caruso Iso-bond stuff. Because the Fibreblock stuff is probably very low in GFR even in the 30kg/m3 version. I'm judging this by the looks atm, since the "hairy" stuff must be thin fibre. thick fibre stuff get's closer to the look of foam.
Also, if you have a look at the documents I posted above, if you have two materials with same thickness which test iqual in the standard absorbtion tests, they must have the same GFR (even if not same density)

I have used rockwool (32kg/m3) before, and it sucks. not only when building, but it gets worse over the years with humidity (even more if you live by the ocean, like me).
Also the PET stuff can be easily moved. IMO this stuff is more high-tech and worth paying "a little more". In the US it is much more expensive than mineral wool. here it is much closer

respond via personal message, unless you got some on-topic info

Last edited by capoeira; 8th August 2019 at 06:17 PM..
Old 9th August 2019
  #170
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lol. this study for ISO 9053 shows that the test results are not reliable at all. at least not for us where 8000 and 14000 make a huge diference: https://www.researchgate.net/publica...y_Measurements
Old 10th August 2019
  #171
Gear Maniac
 

Quote:
Originally Posted by capoeira View Post
HI. I am so happy to see your post. I am researching a lot these days.
I don't agree with the much more expensive part. we are kind of lucky here.
Here is an offer with prices on mineral wool level for example: https://www.vibrashop.com.br/la-de-p...12-pacote-p121
though I suspect this is 2000 Pa.s/m2 (or even lower) stuff.
I'm aming for 4000 or 5000 since the 2000 stuff would require the dubble amount of material at my aimed thickness to have the same effect: http://www.acousticmodelling.com/mli...&s42=1&d42=200

I found out we have 3 products available:

Fiberblock: which is probably the Vibrasom stuff and is dificult to find data (found only one graph which Vibrasom told me it is for the 50mm/30kgm3 stuff)

Isosoft from Trisoft: they have a PDF with some data, tests more focused on drywall aplication, though

Ecofibre: I have a nice PDF with 8 "laudos"


I'm atm trying to find out which (if) of the last two is close to Caruso Iso-bond stuff. Because the Fibreblock stuff is probably very low in GFR even in the 30kg/m3 version. I'm judging this by the looks atm, since the "hairy" stuff must be thin fibre. thick fibre stuff get's closer to the look of foam.
Also, if you have a look at the documents I posted above, if you have two materials with same thickness which test iqual in the standard absorbtion tests, they must have the same GFR (even if not same density)

I have used rockwool (32kg/m3) before, and it sucks. not only when building, but it gets worse over the years with humidity (even more if you live by the ocean, like me).
Also the PET stuff can be easily moved. IMO this stuff is more high-tech and worth paying "a little more". In the US it is much more expensive than mineral wool. here it is much closer

respond via personal message, unless you got some on-topic info
thanks! your links will be very useful as some of them are actually geographically close to me. Will call them and see what info I can gather and (if useful) post here
Regarding "materials with same thickness", in Sound Flow you can input both values (density and gfr). I usually check it in AFMG's software but real struggle is to have access to the actual information from manufacture.
talk soon via PM
Old 10th August 2019
  #172
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Quote:
Originally Posted by Mauricio Gargel View Post
thanks! your links will be very useful as some of them are actually geographically close to me. Will call them and see what info I can gather and (if useful) post here
Regarding "materials with same thickness", in Sound Flow you can input both values (density and gfr). I usually check it in AFMG's software but real struggle is to have access to the actual information from manufacture.
talk soon via PM
I tried to discuss GFR of our products here: https://www.htforum.com/forum/thread...-vidro.323774/
I think it would be intresting to brainstorm the issue there. Else > PM

I am not positive to get any oficial GFR numbers though.
http://www.ipt.br/consultas_online/ensaios/por_norma for example doesn't even offer tests for ISO 9053

BTW: found a fourth product: http://www.ecofiber.ind.br/nossos-pr...ecofiber-sound

we could also create a topic about polyester fibre there at HTforum. Noone ever seamed to discuss this in our forums


EDIT: and a fifth product: http://www.isopur.com.br/la-de-pet.html

Last edited by capoeira; 10th August 2019 at 03:51 PM..
Old 2 weeks ago
  #173
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I received communication from Owens-Corning this morning (Sept 4, 2019) that the average gfr for 703 is 18,000 rayls/m.
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