Design and Evaluation of a Personal Diffusion Battery

Figures & data

FIG. 1 (a) Personal diffusion battery (pDB) that can be placed in a backpack. (b) Airflow through each stage of pDB.

FIG. 2 Experimental set up to test the pDB+CPC with inversion spreadsheet using combustion aerosols.

TABLE 1 Original distributions and simulated inversion distribution results for the lower and upper NMD that could be distinguished with the pDB+CPC inversion and the results for the distributions with NMD below the lower limit and above the upper limit

Original distribution			Inversion distribution
		Number concentration			Number concentration
NMD (nm)	GSD	(particle cm^−3)	NMD (nm)	GSD	(particle cm^−3)
16	1.40	50,000	17	1.3^a,b	47,489
16	2.00	50,000	16	2.00	49,982
16	2.80	50,000	16	2.80	50,003
17	1.40	50,000	17	1.40	49,997
17	2.00	50,000	17	2.00	49,993
17	2.80	50,000	17	2.80	50,010
286	1.40	50,000	287	1.41	50,010
286	2.00	50,000	281	1.98	49,755
286	2.80	50,000	286	2.80	49,987
287	1.40	50,000	310	1.52^b	50,343
287	2.00	50,000	282	2.00	49,726
287	2.80	50,000	285	2.79	49,851
^aRepresents inversion results that solved to a constraint.
^bRepresents inversion results when one of the following occurred: the inversion distribution NMD was more than ±10% different from the original distribution NMD, the inversion distribution GSD was more than ±5% different from the original distribution GSD, or the inversion distribution number concentration was more than ±5% different from the original distribution number concentration.

TABLE 2 Inversion distribution results for varying number of pDB+CPC stages to determine minimum number of stages required for the NMD particle size range of 17–286 nm

	Lower limit distribution			Upper limit distribution
	NMD = 17 nm, GSD = 1.4			NMD = 286 nm, GSD = 1.4
	number concentration = 50,000			number concentration = 50,000
Data			Number			Number
inversion	NMD		concentration	NMD		concentration
stages	(nm)	GSD	(particle cm^−3)	(nm)	GSD	(particle cm^−3)
A,B	18	1.3^b	48,241	272	1.3^a,b	49,847
B,C	500^a,b	3.0^a,b	38,092^b	304^b	1.50^b	50,251
C,D	500^a,b	3.0^a,b	38,092^b	273	1.3^a,b	49,837
A,C	18	1.3^a,b	47,912	272	1.3^a,b	49,852
B,D	500^a,b	3.0^a,b	38,092^b	303^b	1.49^b	50,247
A,D	19^b	1.3^a,b	47,675	272	1.3^a,b	49,857
A,B,C^c	17	1.40	49,996	278	1.34	49,910
B,C,D	500^a,b	3.0^a,b	38,092^b	273	1.3^a,b	49,847
A,C,D	18	1.31^b	47,947	272	1.3^a,b	49,852
A,B,D^c	17	1.40	49,998	281	1.36	49,940
A,B,C,D^c	17	1.40	49,997	287	1.41	50,010
^aRepresents inversion results that solved to a constraint.
^bRepresents inversion results where at least one of the following occurred: the inversion distribution NMD was ±10% different from the original distribution NMD, the inversion distribution GSD was ±5% different from the original distribution GSD, or the inversion distribution number concentration was ±5% different from the original distribution number concentration.
^cIndicates distributions where all parameters were met.

TABLE 3 Polydisperse aerosol distributions measured with the SMPS and pDB+CPC with inversion spreadsheet. The total number concentration is reported here

		SMPS measured			pDB+CPC with inversion spreadsheet
				Number			Number
				concentration			concentration
Aerosol	Timing (s)	NMD (nm)	GSD	(particle cm^−3)	NMD (nm)	GSD	(particle cm^−3)
Propylene torch	240	15	1.49	31,378	16^a	1.38	33,898
Propylene torch	240	15	1.42	29,302	16^a	1.36	27,544
Propylene torch	240	15	1.42	21,187	16^a	1.30	23,457
Incense	240	107	1.75	96,022	156^b	1.3^a, b	64,160^b
Incense	240	97	1.74	114,793	87	1.56	103,647
Incense	240	97	1.82	131,896	131^b	1.3^a,b	107,312
Propylene torch	80	17	1.43	43,633	18	1.30	37,782
Propylene torch	80	17	1.49	42,725	19	1.32	37,618
Propylene torch	80	17	1.43	37,955	18	1.36	35,945
Incense	80	97	1.57	56,766	69^b	1.3^a	46,220
Incense	80	97	1.74	82,325	95	1.52	77,969
Incense	80	97	1.57	72,589	113	1.3^a	66,139
^aRepresents inversion results that solved to a constraint.
^bRepresents inversion results when one of the following occurred: the pDB+CPC with inversion spreadsheet distribution NMD was ±25% different from the SMPS measured distribution NMD, the pDB+CPC with inversion spreadsheet distribution GSD was ±25% different from the SMPS measured distribution GSD, the pDB+CPC with inversion spreadsheet distribution number concentration was ±25% different from the SMPS measured distribution number concentration.

TABLE 4 Nanoparticle number concentrations measured with the pDB+CPC with inversion spreadsheet and the SMPS

		pDB+CPC nanoparticle	SMPS nanoparticle
Aerosol	Timing (s)	(particle cm^−3)	(particle cm^−3)	R nano
Propylene torch	240	32,286	31,378	1.03^a
Propylene torch	240	26,417	29,302	0.90^a
Propylene torch	240	22,950	21,187	1.08^a
Incense	240	2,720	46,348	0.06^a,b
Incense	240	63,873	63,487	1.01
Incense	240	15,471	70,144	0.22^a,b
Propylene torch	80	37,766	43,633	0.87
Propylene torch	80	37,623	42,725	0.88
Propylene torch	80	35,229	37,955	0.93
Incense	80	42,463	21,115	2.01^a,b
Incense	80	42,400	46,499	0.91
Incense	80	20,213	38,574	0.52^a
^aRepresents inversion results that solved to a constraint.
^bRepresents inversion results when one of the following occurred: the pDB+CPC with inversion spreadsheet distribution NMD was ±25% different from the SMPS measured distribution NMD, the pDB+CPC with inversion spreadsheet distribution GSD was ±25% different from the SMPS measured distribution GSD, the pDB+CPC with inversion spreadsheet distribution number concentration was ±25% different from the SMPS measured distribution number concentration.

FIG. 3 Comparison of the three propylene torch runs measured by the SMPS and the pDB+CPC with inversion spreadsheet for the (a) 240-s measurements and (b) 80-s measurements.

FIG. 4 Comparison of the three incense runs measured by the SMPS and the pDB+CPC with inversion spreadsheet for the (a) 240-s measurements and (b) 80-s measurements.