Concerning The Temperature Dependence Of Pressure Sensitive Paints

Luminescent molecule sensors, called pressure-sensitive paint (PSP) and temperature-sensitive paint (TSP), measure factors essential for understanding the aerodynamic performance and heat transfer characteristics of flight vehicles. They provide a powerful tool for experimental aerodynamicists to obtain a deeper understanding of the rich physical phenomena in complex flows around a flight vehicle. This book helps the reader to understand the physics and chemistry and the capabilities of PSP and TSP. It provides an overview of the wide scope of applications and explains the system requirements for using these sensors. The book also includes an extensive table of properties of PTP and TSP. As such, it is a thorough and up-to-date coverage of the underlying physics and applications of luminescent molecules designed for global pressure and temperature mapping

Luminescent molecule sensors, called pressure-sensitive paint (PSP) and temperature-sensitive paint (TSP), measure factors essential for understanding the aerodynamic performance and heat transfer characteristics of flight vehicles. They provide a powerful tool for experimental aerodynamicists to obtain a deeper understanding of the rich physical phenomena in complex flows around a flight vehicle. This book helps the reader to understand the physics and chemistry and the capabilities of PSP and TSP. It provides an overview of the wide scope of applications and explains the system requirements for using these sensors. The book also includes an extensive table of properties of PTP and TSP. As such, it is a thorough and up-to-date coverage of the underlying physics and applications of luminescent molecules designed for global pressure and temperature mapping

In order to obtain quantitative surface pressure measurements of a transonic compressor rotor using pressure sensitive paint (PSP), the temperature dependence of the paint must be taken into consideration. In the present study, a calibration chamber was built and instrumented such that pressure and temperature could be controlled independently. Photodiodes were used to measure the intensity of light emitted by the PSP. An acquisition program was developed to record the necessary calibration data to obtain an analytical representation of the luminescent response of the pressure-sensitive paint over a range of pressures and temperatures characteristic of transonic fans.

In the development of a surface pressure measurement system for transonic compressor rotors, it has been shown that Pressure Sensitive Paint (PSP) is also temperature dependent. In the present study, the sensitivities to pressure and temperature were examined experimentally using an electronically- gated, intensified Charged- Coupled-Device (CCD) video camera, frame-grabber software and an eight-inch diameter calibration chamber. Using a signal generator, in a procedure that matched the requirements of the rotor application, multiple low-intensity-level camera exposures were integrated and captured to produce a single usable image. Ten captured images were averaged to increase the image's signal-to-noise ratio and the result was used to produce an image ratio with respect to a static (ambient pressure/temperature) reference condition. Calibration tests of constant temperature/variable pressure and constant pressure/variable temperature were completed. The results were then compared with data obtained using the same paint and an automated, single- exposure calibration procedure at NASA Ames Research Center. It was shown that the calibration data could be used to derive the static pressure field produced over a high-speed test rotor using PSP and the same image-capture system used in the calibration. In preparation for a bench test of the procedure, a uniform- stress, high-speed test rotor disk, fitted with a shock generator was driven at speeds in excess of 30,000 RPM. Recommendations are made toward the goal of obtaining quantitative pressure measurements on transonic compressor rotors.

Co-Sponsored by the ISA Aerospace Industries and Test Measurement Divisions, the conference proceedings include information about the latest developments in measurement uncertainty; computer applications; data acquisitions and processing; MEMS design, analysis and fabrication; pressure; blast and shock; and laser applications.

This new edition describes pressure and temperature sensitive paints (PSP and TSP) in global surface pressure and temperature measurements in aerodynamics and fluid mechanics. The book includes the latest progress in paint formulations, instrumentation, and steady and unsteady aerodynamic measurements in various facilities including low-speed, transonic, supersonic and hypersonic wind tunnels. The updated technical aspects of PSP and TSP in the book will be useful for students and researchers in experimental aerodynamics and fluid mechanics.

Over the last decade, fluorescence has become the dominant tool in biotechnology and medical imaging. These exciting advances have been underpinned by the advances in time-resolved techniques and instrumentation, probe design, chemical / biochemical sensing, coupled with our furthered knowledge in biology. Complementary volumes 9 and 10, Advanced Concepts of Fluorescence Sensing: Small Molecule Sensing and Advanced Concepts of Fluorescence Sensing: Macromolecular Sensing, aim to summarize the current state of the art in fluorescent sensing. For this reason, Drs. Geddes and Lakowicz have invited chapters, encompassing a broad range of fluorescence sensing techniques. Some chapters deal with small molecule sensors, such as for anions, cations, and CO2, while others summarize recent advances in protein-based and macromolecular sensors. The Editors have, however, not included DNA or RNA based sensing in this volume, as this were reviewed in Volume 7 and is to be the subject of a more detailed volume in the near future.

Measurement of the static-pressure distribution over the surface of a rotor disk was attempted using pressure sensitive paint (PSP). A uniform stress, high speed rotor disk, fitted with a shock generator, was built, installed and operated at speeds in excess of 20,000 RPM by a Hamilton Standard turbine driven fuel pump. A once per revolution trigger signal was converted to a transistor to transistor logic (TTL) format and used to gate an intensified charged coupled device (CCD) video camera. Multiple low intensity level camera exposures were integrated and captured to produce a single usable image. Ten captured images were averaged to increase the image's signal to noise ratio and the result was used to produce an image ratio with respect to a static reference condition. Finally, a pseudo coloring process was used to develop a color image that related intensities to both temperature and pressure distributions in accordance with the Stern-Volmer relation. Paint stripping and temperature dependence prevented the measurement of pressure at transonic speeds. The test bed facility and acquisition techniques developed here could now be used to overcome those limitations.