Temperature/Heat Flux Imaging of an Aerodynamic Model in High-Temperature, Continuous-Flow Wind Tunnels

Period of Performance: 01/01/2015 - 12/31/2015

$149K

Phase 1 SBIR

Recipient Firm

Innovative Scientific Solutions, Inc.
7610 McEwen Road Array
Dayton, OH 45459
Principal Investigator

Abstract

ABSTRACT:Heat transfer is an important quantity that remains difficult to predict using CFD. Phenomena such as transition and separation are difficult to capture with discrete sensors. Temperature-Sensitive Paint is an image-based technology that has been used for over 25 years to acquire measurements of surface temperature and heat flux in a variety of flows. The major limitation to deploying TSP systems in AEDC Tunnel B/C, where temperatures are between 600 F and 2000 F, is the availability of an appropriate TSP. Standard TSPs utilize polymer materials that will not survive long-duration testing at elevated temperatures while traditional phosphor-based TSPs employ coatings that cannot be removed without damaging the model surface. Recently, ISSI has developed phosphor-based TSP systems that address these issues. The TSP system is composed of a surface layer of a carbon compound that is over sprayed with a phosphor based TSP in a high temperature binder. The carbon compound adheres to the surface, but is non-reactive at elevated temperatures. Removal of the TSP system is accomplished using a Teflon spatula and then the carbon layer is removed using Acetone. The objective of this proposal is to deploy a TSP-based system for acquiring heat flux measurements in Tunnel B/C.BENEFIT:A system that can provide global measurements of heat flux on a model in a high temperature wind tunnel would be of value for future CFD validation and hypersonic designs. Temperature-Sensitive Paint is an image-based technology that has been used to acquire measurements of surface temperature and heat flux in wind tunnels. The major limitation to deploying TSP systems in AEDC Tunnel B/C, where temperatures are between 600 F and 2000 F, is the availability of an appropriate TSP. Recently, ISSI has developed phosphor-based TSP system that can be applied with an air-brush, operated at temperatures over 900 F, and removed with a Teflon spatula and Acetone. ????The overall objective of the program is to deploy a TSP-based system for acquiring surface temperature, heat flux, and heat transfer measurements in AEDC Tunnel B/C. The technical maturity and accuracy of the TSP technique has been demonstrated in numerous wind tunnel experiments. The potential to deploy a production data acquisition and processing TSP system is demonstrated by the commercial PSP/TSP systems that have been installed by the proposing team. It is noted that the market for TSP measurements in high temperature wind tunnels is limited, however, the fundamental technology that is key to the proposal, optical measurements of surface temperature has applications in a variety of markets. It is well known that gas turbine engine manufactures would like to deploy CMCs to both reduce weight and increase efficiency of these engines. Uniform film cooling of the CMC is required to prevent cracks in the CMC. An experimental system that could measure these temperatures on test rigs would be useful for evaluating the effectiveness of film cooling designs. ISSI is a key commercial source of PSP/TSP technology worldwide, with customers in the US, Japan, Korea, and several countries in the EU. Total sales from this technology are now over $1,000,000 per year with significant growth seen each of the last 6 years. Several commercial customers have expressed interest in a high temperature measurement capability. With our current market position, ISSI will be able to market this new capability to existing customers as well as develop new customers. ??