NASA has announced the development of its unsteady Pressure Sensitive Paint (uPSP) system, capable of capturing high-resolution, real-time data on turbulent airflow and unsteady flow separation.
This advanced technology system – capable of replacing individually applied dynamic pressure transducers – has the potential to transform how airflow in wind tunnels is studied as it moves over aircraft using optical measurements.
The uPSP system delivers results 10,000 times faster and 1,000 times more detailed than previous methods, providing research engineers with near-instantaneous feedback that was previously impossible to achieve. By converting wind tunnel data into high-speed, ultra-detailed visualisations, NASA is looking to change how engineers test, design and perfect the next generation of flight technology.
NASA Ames was responsible for developing uPSP, which couples recent advances in high-speed cameras, high-powered energy sources and fast response pressure-sensitive paint.
The setup allows time-resolved measurements of unsteady pressure fluctuations within a dense grid of spatial points on a wind tunnel model.
The uPSP is applied quickly using a spray gun – if the model geometry can be painted, viewed from a camera and excited by a lamp source, then uPSP data can be collected – substantially reducing the time between data gathering and analysis, and reducing the number of transducers required, which provides a significant cost reduction.
“One of the challenges in making accurate simulation software packages – let alone accurate results – is being able to have something based in reality, based in real physics, to compare it to. The better [the] data we can collect in a wind tunnel environment, that means the better the simulations are so we can trust the results even more,” explained Dr Lara Lash, aerospace engineer at NASA Ames Research Centre.