System and method for unified sampling of particulate matter for reducing the dispersion of results in vehicle emissions tests

Patent metadata

Field	Value
Publication number	US-12405189-B2
Application number	US-202218081845-A
Country	US
Kind code	B2
Filing date	Dec 15, 2022
Priority date	Dec 15, 2021
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

The present invention provides a system and a method for determining the particulate matter mass in vehicle emissions tests, seeking to improve weighing resolution and reduce experimental uncertainties. The invention presents two embodiments, in which in the first embodiment there is a branch in the vehicle emissions collection equipment that allows to integrate the particulate matter generated during the entire test into a single filter. In the second embodiment, there are two branches in which one branch has a filter for the accumulation of the particulates produced in phases 1 and 2 of the test and the other branch has another filter for the accumulation of the particulates in phases 2 and 3.

First claim

The invention claimed is:

1. A sampling system of particulate matter for vehicle emission tests, the system comprising:
a probe configured to sample vehicle emissions carrying particulate matter, the probe directing the sampled particulate matter into a channel of a plurality of channels;
a filter holder positioned within at least one of the plurality of channels, wherein at least one of the plurality of channels does not include a filter holder;
valves arranged and configured to direct the vehicle emissions into a specified channel of the plurality of channels;
a sampling pump configured to flow the vehicle emissions through at least one channel of the plurality of channels; and
a mass flow meter arranged to receive the vehicle emissions from the plurality of channels;
a balloon configured to reduce pulsations in the mass flow meter caused by the sampling pump;
a cylinder configured to reduce pulsations in the mass flow meter caused by the sampling pump; and
a return arranged to direct the flow to a constant volume sampler.

2. The system according to claim 1 , wherein the probe has a minimum internal diameter of 12.7 mm.

3. The system according to claim 1 , wherein the filter holder is configured to hold a filter that is configured to retain the particulate matter.

4. The system according to claim 3 , wherein the valves are configured to direct the vehicle emissions to at least one channel of the plurality of channels that includes the filter holder, holding the filter, in each phase of the test, or to the at least one channel of the plurality of channels not including a filter holder before and after the test.

5. The system according to claim 1 , wherein the mass flow meter is configured to measure the vehicle emissions during the test.

6. The system of claim 1 , wherein the plurality of channels comprises three channels, the system further comprising an additional channel in which a three-phase mass will be accumulated.

7. The system of claim 1 , wherein the plurality of channels comprise three channels, wherein the filter holder is a first filter holder, wherein the particulate matter from steps 1 and 2 of an emission test are directed through a first of the plurality of channels including the first filter holder and steps 2 and 3 of the emissions test are directed through the second of the plurality of channels including a second filter holder, wherein the particulate matter is accumulated within filters housed by the first filter holder and the second filter holder.

8. A unified sampling method of particulate matter for reducing dispersion of results in a vehicles emissions test, the method comprising:
extracting vehicle emission gases from a dilution tunnel (DT) to a hydrocarbon flame ionization detector by the probe of claim 1 , wherein the probe is installed in front of the flow at a point where the vehicle emission gases and dilution air are homogenized, the point being a sufficient radial distance from the point;
directing the vehicle emission gases extracted by the probe to a first channel of a plurality of channels prior to a start of an emission test, the first channel of the plurality of channels being free of a filter and filter holder;
directing the vehicle emission gases into a second channel of the plurality of channels during the vehicle emission test, the second channel including a filter holder with a filter;
measuring a mass of the filter prior to the vehicle emission test;
measuring a mass of the filter after the vehicle emission test and determining a difference between the mass of the filter before and after the vehicle emission test;
measuring a temperature and controlling a flowrate, by a flow control instrument, of the vehicle emission gases during the vehicle emission test; and
directing the vehicle emission gases to a balloon that reduces the pulsation caused by a pumping system in a mass flow meter during the vehicle emission test; and
directing the vehicle emission gases to a constant volume sampler.

9. The method according to claim 8 , wherein the probe is located at a center line of the DT and at a distance of at least ten times a diameter of the DT, from a point where the gas enters the DT.

10. The method according to claim 8 , wherein the probe is free from influences of vacuums produced by the particulate matter sample probe.

11. The method according to claim 8 , wherein the flow rate of the vehicle emission gases is maintained at a constant value, within 5%.

12. The method according to claim 8 , wherein the temperature of the vehicle emission gases is maintained at a constant value, within 2.8° C.

Assignees

• Petroleo Brasileiro Sa Petrobras
• Inst De Tecnologia Para O Desenvolvimento Lactec
• Petroleo Brasileiro S A —Petrobras

Inventors

• Scardini Villela Antonio Carlos
• Cavalcante Cordeiro De Melo Tadeu
• Pazello Chedid Juliano
• Rempel Dennis
• Corrêa Luiz Carlos
• Daemme Luiz Carlos
• Caffaro Vicentini Pedro
• De Arruda Penteado Neto Renato

Classifications

• G01N15/0618

  of the filter type (G01N15/0643 takes precedence) · CPC title

• G01N1/38

  Diluting, dispersing or mixing samples · CPC title

• G01N2001/2255

  with dilution of the sample · CPC title

• G01N1/2252

  in a vehicle exhaust · CPC title

• G01N2015/0046

  in gas, e.g. smoke · CPC title