Particle
Acceleration
NozzleParticleCollection
NozzleParticleCollector

Conforms to JIS · ISO sampling method of PM 2.5 / PM 10 in flue exhaust gas(JIS Z 7152 / ISO 13271)

Summary / Feature
Virtual impactor VI-2.5 is a product which canclassify and sample a particle group into three
types such as over 10 μm, 10 ~ 2.5 μm and below
2.5 μm, using a two-step virtual impactor.
Different from the traditional cascade impactor
system or cyclone system, the virtual impactor
system has a structure that prevents particle rescattering or rebounding and thus enables tomeasure particles in the flue more accurately.
Moreover, by use of digital monitoring unit which displays instant / integral suction flow rate anddata logger, the record can be left when sampling and the flow monitoring work could also be reduced.
This product conforms to JIS Z 7152: 2013 「Measurement method of PM 10 / PM 2.5 massconcentration in exhaust gas by virtual impactor」 and ISO 13271: 2012.

TOKYO DYLEC CORP.

Principle of Measurement

5Q01D0l0s
3Q2Q2D1412345D0D1l0s
Q0Q1Q2Q1

2

Particle acceleration nozzle
Particle collection nozzle
Locus of the fine particles in the mainstream
Locus of the coarse particles in the side stream
Gas stream line
Particle acceleration nozzle diameter
Particle collection nozzle diameter
Particle acceleration nozzle length
Distance from exit of particle acceleration nozzle to entrance of particle collection nozzle
Total flow rate
Flow rate of the side stream
Flow rate of the mainstream

The classification of virtual impactor is based on the principle that when particles
accelerate or slow down in a gas flow, particles swerve from the streamline of gas by inertia.
The main parameters which determine operating principle and performanceof classification stage are shown in the upper figure.
First, the basic composition of classification part is made of a particle acceleration nozzle
and a particle collection nozzle. They are in the same axis and the diameters are D0 and D1
respectively.
Next, sampled gas flows through the nozzle and is accelerated according to D0 and thetotal flow, and then the part of the flow goes to the direction of the collection nozzle.
The flow rate which flows through a particle collection nozzle (called side stream flowrate) is about 10% of the total flow rate, and the main portion ( the mainstream ) of the flowchanges direction and bypass the collection nozzle. As a result, particles which
are larger than a certain diameter of aerodynamics (cut-off size) accompany with the sidestream and go through the collection nozzle, and then are collected on a collection filter.
Particles which are smaller than cut-off size move to next classification part accompaniedwith mainstream.

TOKYO DYLEC CORP.

Structure
5 types of inner diameter of top nozzle
φ3.5, 4, 4.5, 5, 6 mm

FilterExtended probemodel
VI-2.5Z※VI-101※VI-102
VI-103
VI-104
VI-105
VI-106※VI-107※VI-108
VI-109
VI-110
VI-111
VI-112
VI-113
VI-114
VI-115
VI-116items
A set of Virtual Impactor VI-2.5
Including the model with ※ mark（VI-101, 102（selectable nozzle diameter ）, 107, 108）
Virtual Impactor, bodyNozzle 3.5mm, made from titanium, type L
Nozzle 4.0mm, made from titanium, type L
Nozzle 4.5mm, made from titanium, type L
Nozzle 5.0mm, made from titanium, type L
Nozzle 6.0mm, made from titanium, type L
Carrying caseProbe tube, made from SUS, length：80cm
Suction pump for the 10.0μm sampling line
Suction pump for the 2.5 to 10.0μm sampling line
Suction pump for the 2.5μm sampling line
Wet type gas meter for 1L, with center cable
Wet type gas meter for 5L, with center cable
Digital recorder
Digital indicator, with 3 lines
Stand for impactor※ Please feel free to contact us for more information about nozzles of other sizes as well as probe tubes.

Flow Diagram
3210μm（Dp50） or lager
12.5~10μm（Dp50）

2.5μm（Dp50） or smaller

アナログ出力

1.
2.
3.
4.
5.

Virtual impactor
Suction pump
Wet type gas meter
Digital indicator
Data logger

45＊Please do not hesitate to consult about line composition.

Specification
Virtual Impactor
Outside dimension

V.I body

Suction nozzle

Tip diameter

φ3.5mm/φ4mm/φ4.5mm/φ5mm/φ6mm （selective）

V.I. bodyPM2.5: 10.3 L/min
2.5-10 μm: 1.2 L/min
Over 10 μm: 1.0 L/min

Suction flow rate

L150mm×φ77mm

Option3 lines indication

Digital Indicator
Digital recorder(10μm,10-2.5μm, 2.5μm)

Sampling time, integral flowrate etc.

Indicate instant flow rate and integral flow rate
Record large quantity of detailed information

10μm or lager
Sample line ※1

W-NKDa-1B

2.5~10μm sample line ※1

W-NKDa-1B

2.5μm or smaller
Sample line※1

W-NKDa-2.5B

Sampling pumpEvery Sample line

Please inquiry for more information

Sampling hose

Every Sample line

Please inquiry for more information

Wet type gasmeter※1 Cut off diameter means 50% of separate efficiency＊Please contact us if you want a different specification or line composition.

＊The specification may be changed without notice.

TOKYO DYLEC CORP.
Head Office:Naitocho Bldg, 1 Naito-Machi, Shinjuku-Ku, Tokyo 160-0014, Japan
TEL: +81-3-3355-3632

FAX: +81-3-3353-6895

http://www.t-dylec.net/

e-mail：info@tokyo-dylec.co.jp

Nishinihon Office:53-4 Nakagoryo-cho, Higashikujo, Minami-ku, Kyoto 601-8027
TEL: +81-75-672-3266 FAX: +81-75-672-3276

Oct 2017