"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
An endoscopic particle image velocimetry (PIV) system and multiprocessor computer will be acquired for mechanical and biomedical engineering fluid mechanics research and projects at the Cooper Union. The PIV system is designed for visualizing and measuring two-dimensional velocity and turbulence fields in steady and unsteady flows of gas or liquid, at sample rates up to 15 fields per second, in internal flow devices with restricted optical access. Conventional light sheet optics will be acquired for use in wind tunnels and other optically accessible experiments. The multiprocessor computer is a custom 16-core workstation with 64 GB of RAM, designed for large computational fluid dynamics model simulations. These powerful tools will be used to train masters and undergraduate students in fluid mechanics research using both experimental and computational methods, in a variety of projects, including fluid mechanics of rigid and deformable models of the upper airway in obstructive sleep apnea, fluid mechanics of chronic cyclic hypoxia research equipment, improved in-cylinder flow characteristics in homogeneous charge compression ignition engines to reduce hydrocarbon emissions, and a variety of undergraduate automotive and wind tunnel projects. Undergraduate students will be exposed to PIV in required fluid mechanics and lab courses, and will be able to receive training and apply PIV to research and design projects. Students taking computational fluid dynamics courses will be introduced to parallel processing and have the opportunity to use the multiprocessor workstation during course projects as well as research projects.
The goal of this project was to acquire, install, and demonstrate a particle image velocimetry (PIV) system and a multiprocessor engineering computer workstation, suitable for experimental research in biofluid mechanics and mechanical engineering, and undergraduate and graduate student projects. The resulting PIV system has been acquired and installed at the Cooper Union. The system consists of a commercial two-dimensional single camera PIV system with advanced timing unit, standard and macro/telephoto camera optics, cylindrical lens laser sheet optics, laser endoscope, and camera endoscope, and aerosol generator (LaVision), and custom laser safety enclosure and interlock. The PIV system is capable of air flow field measurements using liquid droplet particles, liquid internal flow field measurements in refractive-index-matched transparent flow models, and local flow field measurements in opaque or non-index matched flow conduits using the endoscopes. The advanced timing unit enables phase-locked or event-triggered data acquisition and ensemble averaging in unsteady flows. Combined with available 3D rapid prototyping tools for lost core model construction, this new system supports a wide variety of flow experiments for image-based biofluid mechanics modeling, for analyzing and developing prototype designs, and for educational uses including demonstration of internal pipe flow mean velocity profiles and turbulent velocity distributions. The system has been used for laboratory wind tunnel measurements, on prototype chambers used for research on hypoxia, and in a collaborative study of the flow field in a two-stream reaction chamber with ultrasonic mixer. The multiprocessor computational workstation has been used to compute airflow, pressure, and turbulence fields in the upper airway of human subjects, based on medical images. These models have been used to better understand the relationship between airway anatomy and airway pressure distribution and to estimate the local airway mechanical compliance in individual subjects, and to relate these quantities to the presence and severity of obstructive sleep apnea syndrome. The combined computational resources and PIV system will support computational model validation studies in rigid and deformable airway models.
