Interdisciplinary Consulting Corporation proposes a sensor that offers the unique capability to make wall shear stress measurement and pressure measurements for time resolved, unsteady hypersonic measurements in NASA facilities. An all sapphire optical-based sensor scheme will facilitate high bandwidth, high resolution, and robust sensors for both skin friction and pressure measurements in harsh hypersonic flow environment. The proposed shear stress sensor possesses utilizes Moire based technique for non intrusive remote data acquisition using sapphire fibres. The pressure sensor utilizes an optic lever-based measurement scheme. Both the shear and pressure sensor are co-located on a single die for localized surface stress measurement. A robust and compact package with miniature interface electronics enables flush sensor mounting conformal with the surface. The sensor development effort focuses on novel pico-second laser micromachining techniques for fabrication on sapphire with minimal heat damage to maintain original sensor material properties. Furthermore, sapphire's high transparency (170 nm to 5.3 ?m wavelength range) along with the availability of sapphire optical fibers make possible the fabrication of optical sensors with the electronics located remotely from the sensor. Sapphire wafers are also readily available in numerous sizes and crystallographic orientations. The sensor will exceed its predecessors in performance and will offer hypersonic surface stress measurement capabilities that are currently insufficient.
Potential NASA Commercial Applications: (Limit 1500 characters, approximately 150 words) Skin friction and pressure measurement for hypersonic flow conditions will enable NASA ATP facilities to precise stress measurement under harsh conditioned, which is currently not possible. This capability provides scientific value and poses significant commercial gain to NASA ATP by means of providing aerodynamic design and testing opportunity to the aerospace industry. Specific NASA ATP facilities that will benefit from precise skin friction instrumentation for aerodynamic performance estimation are, Aerothermodynamic Laboratories Facilities (31-inch Mach 10 Air, 20-inch Mach 6 Air , 20-inch Mach 6 CF4, and the 12-inch Mach 6 Air) to enable studies of aerodynamic performance of hypersonic vehicle components. In addition to the hypersonic testing at LaRC, the proposed innovation is also applicable to some of NASA Glenn Research Center's Propulsion System Laboratories. Overall, NASA and the aerospace industry stand to significantly benefit via better aerodynamic design and higher efficiency/ lower drag at lower cost.
Potential NON-NASA Commercial Applications: (Limit 1500 characters, approximately 150 words) Several research institutes, aerospace companies perform routine wind tunnel testing hypersonic regimes. Gas turbine for better power generation and combustion study and control, evaluation of flame front propagation during combustion are some other areas where this technology will be very applicable. Industrial process control in harsh high temperature conditions such as petroleum refineries are other potential applications. This sensor may also serve as a platform technology with a potential impact on a broad application spectrum that ranges from fundamental scientific research, biomedical applications, etc.
Technology Taxonomy Mapping: (NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) Microelectromechanical Systems (MEMS) and smaller
