Grantee Research Project Results

2010 Progress Report: Quantifying the Effects of the Mixing Process in Fabricated Dilution Systems on Particulate Emission Measurements via an Integrated Experimental and Modeling Approach

EPA Grant Number: R834561
Title: Quantifying the Effects of the Mixing Process in Fabricated Dilution Systems on Particulate Emission Measurements via an Integrated Experimental and Modeling Approach
Investigators: Zhang, Ke Max
Institution: Cornell University
EPA Project Officer: Chung, Serena
Project Period: May 1, 2010 through April 30, 2013 (Extended to October 30, 2013)
Project Period Covered by this Report: May 1, 2010 through April 30,2011
Project Amount: $250,000
RFA: Novel Approaches to Improving Air Pollution Emissions Information (2009) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Air

Objective:

The main objective of the proposed study is to investigate a key uncertainty in PM emissions measurements by examining the following questions: How do mixing processes in current constant volume sampler (CVS) systems differ from those in real-world conditions? How do mixing processes in different CVS systems differ from each other? How does the mixing process interact with the aerosol dynamics that affect PM measurements in CVS systems and PM transformation in the atmosphere?

Progress Summary:

We have developed a new turbulent reacting flow model, named CTAG, and evaluated CTAG against several field measurements of the evolution of particle size distributions in dilution exhaust plumes. In addition, we have simulated turbulent mixing and aerosol dynamics inside two dilution tunnels. The results provided quantitative descriptions of how turbulent mixing affects measurements of particle size distributions.

Future Activities:

We will investigate the sensitivity of PM measurements to several important parameters in dilution tunnel design (e.g., co-axial mixing and tee-mixing). We also plan to compare laboratory emission measurements with on-road emission measurements.

Journal Articles:

No journal articles submitted with this report: View all 5 publications for this project

Supplemental Keywords:

PM2.5, combustion, on-road, non-road, stationary sources, ultrafine, public health, human exposure, climate change

Progress and Final Reports:

Original Abstract

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.