Grantee Research Project Results
2014 Progress Report: Development of Cost-effective, Compact Electrical Ultrafine Particle (eUFP) Sizers and Wireless eUFP Sensor Network
EPA Grant Number: R835132Title: Development of Cost-effective, Compact Electrical Ultrafine Particle (eUFP) Sizers and Wireless eUFP Sensor Network
Investigators: Chen, Da-Ren , Lu, Chenyang
Institution: Washington University , Virginia Commonwealth University
EPA Project Officer: Chung, Serena
Project Period: September 1, 2012 through August 31, 2015 (Extended to August 31, 2016)
Project Period Covered by this Report: September 1, 2013 through August 31,2014
Project Amount: $499,130
RFA: Developing the Next Generation of Air Quality Measurement Technology (2011) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Air
Objective:
Specific objectives of this EPA project are to: (1) develop a cost-effective, portable electrical ultrafine particle (eUFP) sizer, enabling the spatial and temporal monitoring of UFP size distribution in the ambient; (2) develop a cost-effective, pocket eUFP sizer for measuring the UFP exposure at the personal level; (3) develop a wireless mesh network using proposed portable sizers as the nodes, enabling to monitor the working status of deployed sizers and to acquire data being collected via internet; and (4) evaluate and validate proposed technologies in planned field testing.
The primary objectives in Year 2 of this project is to continue developing the core components for miniature electrical Ultrafine Particle Sizers (mini- eUFP sizers) and to assemble the first prototype mini- eUFP sizer. The sizers core components to be developed in Year 2 are mini-plate aerosol charger and mini-plate differential mobility classifier (mini- plate DMC).
Progress Summary:
A mini-plate aerosol charger and differential mobility classifier (DMC), key components of a mini-eUFP sizer, have been developed in Year 2 of this project. Detailed experiments had been carried out to evaluate the performance of a mini-plate aerosol charger and DMC. The calibration results show that both components provide satisfactory performance for a mini-eUFP sizer. The semi-empirical models have also been developed to mathematically predict the performance of the above two components. Further, the first mini-eUFP sizer has been assembled and past the preliminary testing. The full calibration of mini- eUFP sizer is ongoing. In addition to the measurement of ultrafine particle size distribution, the temperature and relative humidity of the aerosol stream are monitored in this fisrt-assembled mini-sizer.
1. Development of New Mini-Plate Aerosol Charger
Figure 1. Schematic diagram of prototype DC-corona-based mini-plate charger
Figure 2. Experimental setup for the performance evaluation of the prototype
Figure 3. Intrinsic positive charging efficiencies and Extrinsic
positive charging efficienties for particles in the size range from
20nm to 60nm
2. Development of New Prototype Mini-Plate Differential Mobility Classifier (DMC)
Figure 4. Schematic diagram of the 2nd version of prototype mini plate DMA
Figure 5. Experimental setup for the performance evaluation of the prototype DMC
Figure 6. Ratio of measured and calculated central
voltages for DMA operated at different cases
Figure 7. Particle penetration curves of different particle sizes when the prototype was operated.
Figure 8. Particle penetration curvesw of different particle sizes when the prototype was operated.
3. Assemble of mini eUFP sizer and Its Software Development
Figure 9. Schematic diagram of the assembled mini-eUFP sizer.
Figure 10. THe overview of prototype mini eUPS.
Future Activities:
The primary activities for Year 3 of this project are to: (1) complete the calibration of the newly assembled mini-eUFP sizer; (2) equip the mini-eUFP sizers with the GPS and wireless functions; (3) assemble six mini-eUFP sizers for proposed field testing; and (4) test the wireless network function of mini- eUFP sizers. The calibration of mini-eUFP sizer will involve the comparison of particle size distributions measured by both mini-eUFP sizer and TSI SMPS. A Collison atomizer to produce polydisperse particles with the mean diameters in the nanometer size range, aerosol dryer and neutralizer and flow controllers will be used in the setup for the calibration. The interface and circuit board for wireless network function are currently under the development (by co-PI) and are expected to complete in the first half of Year 3. The inclusion of GPS and wireless network functions into the mini-eUFP sizers will be carried out during the assembly of six prototype sizers. The last 4 months of Year 1 will be focused on the reliability testing of the sensor network using six mini-eUFP sizers as the nodes. The last task will be performed with the collaboration of the co-PI.
References:
Journal Articles:
No journal articles submitted with this report: View all 19 publications for this projectSupplemental Keywords:
Mini-plate, Differential mobility classifier (DMC), aerosol charger, mini-eUFP sizer, mini-UPSProgress and Final Reports:
Original AbstractThe 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.