2003 Progress Report: Flow Control and Design of Environmentally Benign Spray Systems

EPA Grant Number: R829587
Title: Flow Control and Design of Environmentally Benign Spray Systems
Investigators: Plesniak, Michael W. , Frankel, Steven H. , Sojka, Paul E.
Current Investigators: Plesniak, Michael W. , Frankel, Steven H. , Shu, Fangjun , Sojka, Paul E.
Institution: Purdue University
EPA Project Officer: Richards, April
Project Period: January 1, 2002 through December 31, 2004
Project Period Covered by this Report: January 1, 2003 through December 31, 2004
Project Amount: $350,000
RFA: Technology for a Sustainable Environment (2001) RFA Text |  Recipients Lists
Research Category: Sustainability , Pollution Prevention/Sustainable Development


The object of this research project is to reduce air pollutant emissions by improving droplet transfer efficiency (i.e., reducing overspray and hence reducing particulate and solvent effluents in spray coating processes).

Progress Summary:

Considerable progress was made in achieving the technical objectives for both the experimental and computational components of the investigation.

Experimental Program

To provide a physical understanding of flow control for a spray process and to facilitate computational model development and a benchmark of numerical results, a simple canonical model flow was investigated first. Several building blocks that captured many of the relevant physical processes in spray coating were investigated. First, a large-scale water jet was constructed and probed extensively using laser induced fluorescence (LIF) flow visualization and particle image velocimetry (PIV) to examine the effects of nozzle geometry on the jet structure and spreading. (Solid particles will eventually be introduced into the jet to simulate the action of the smallest spray droplets, which are important to control to achieve increases in transfer efficiency).

The following specific accomplishments were achieved:

• Design and manufacture of new indeterminate origin (IO) nozzle exits
• LIF flow visualization of various configurations
• PIV measurements of velocity fields
      - Baseline plain nozzle (free jet)
      - Optimum IO nozzle free jet (modified 4-point crown nozzle).

Computational Simulations

Companion simulations also have been performed. The following specific objectives have been accomplished:

• Two-phase flow predictions for particle-laden impinging jets suggest that the crown nozzle increases the spreading rate of the jet.

• The Large Eddy Simulation (LES) predictions for the round-nozzle-produced impinging jet are in much better agreement with the experimental data than the previous Reynolds-Averaged Navier-Stokes/Reynolds Stress Model (RANS-RSM) results.

Future Activities:

In the next year, we will perform the following measurements and simulations: (1) measurements and computations of two-phase water-particle jets, (2) large eddy simulations of two-phase flows, and (3) evaluation of IO nozzles in actual sprays.

Journal Articles:

No journal articles submitted with this report: View all 14 publications for this project

Supplemental Keywords:

engineering, particulates, toxics, VOC, pollution prevention, innovative technology, environmentally conscious manufacturing, surface coating, chromium compounds, clean technology, cleaner production, coating processes, coatings, emission controls, phase Doppler particle analyzer, pollution prevention, spray processes, sustainability, sustainable development, waste minimization., RFA, Scientific Discipline, Air, Toxics, Sustainable Industry/Business, Chemical Engineering, air toxics, cleaner production/pollution prevention, Environmental Chemistry, Sustainable Environment, VOCs, Technology for Sustainable Environment, Civil/Environmental Engineering, New/Innovative technologies, Chemistry and Materials Science, Engineering, 33/50, Environmental Engineering, particulates, chromium & chromium compounds, cleaner production, sustainable development, waste minimization, waste reduction, environmentally conscious manufacturing, chemical use efficiency, environmentally friendly technology, overspray reduction, Chromium, lead & lead compounds, clean technology, spray processes, emission controls, environmentally benign spray systems, flow control, coating processes, innovative technology, sustainability, surface coating, phase doppler particle analyzer, innovative technologies, pollution prevention, Volatile Organic Compounds (VOCs), air emissions, coatings, ligament-controlled effervescent atomization technology

Relevant Websites:

http://widget.ecn.purdue.edu/~tfpl Exit

Progress and Final Reports:

Original Abstract
  • 2002 Progress Report
  • Final Report