From 37268d38a4d9e0279b0b4ab2660e6b04e4057691 Mon Sep 17 00:00:00 2001 From: Camron Blackburn <camron.blackburn@cba.mit.edu> Date: Tue, 21 Apr 2020 09:07:16 -0400 Subject: [PATCH] Update README.md --- README.md | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/README.md b/README.md index ce3d1b8..e0181e7 100644 --- a/README.md +++ b/README.md @@ -1,12 +1,21 @@ # COVID-19 Filter Testing ## testing instrument +<img src="./filter_testing.jpg" height="500"> + +<img src="./filter_testing_2.jpg" height="500"> + +<img src="./aerosol_generation.jpg" height="500"> + +<img src="./flow_control.jpg" height="500"> + <img src="./cad_1.png" height="500"> This filter efficency testing device is a blend of ASTM standards F2299, F2101, and the henderson apparatus detailed by Wilkes[^filterPerformance]. compressed air enters at the center of the device and first passes through a HEPA filter (a). +Flowmeters read 0.4 to 4 scfm (standard cubic feet per minute) - 11.3 to 113 lpm. nebulizer needs 5 to 9 LPM (liters per minute). 1 cfm = 28.3 lpm @@ -99,6 +108,18 @@ but can see the particles in the Olympus microscope ### spectrophotometer Implen NP80 nanophotometer picks up 100 nm Au particles! simplest relative measuring technique +## common units & conversions +SCFM: standard cubic feet per minute - defined for a set pressure and temperature, not the actual cubic feet per minute (need to find conversion factor for flowmeter reading). molar flow rate = molar constant * mass flowrate + +LPM: liters per minute, volumetric flow rate + +(s)ccm: (standard) cubic centimeter per minute, mass flow rate (even though it's cubis centimeter) so must take into account fluid/gas density + +conversions: +- 1 scfm = 28,317 sccm + + + ### Resources [^DIYmask]: University of Cambridge [DIY mask efficacy testing](https://www.researchgate.net/publication/258525804_Testing_the_Efficacy_of_Homemade_Masks_Would_They_Protect_in_an_Influenza_Pandemic) [^filterPerformance]: AR Wilkes [The bacterial and viral filtration performance of breathing system filters](https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-2044.2000.01327.x) -- GitLab