The concept proposed is and electro-optic technique that would make it possible to spatially modulate a high power pulsed laser beam to thermoelastically induce focused ultrasound in a test material. being a purely electro-opticdevice, the modulator, and therefore the depth at which the acoustic… More

Holography is one of the most powerful diagnostic tools for dynamic three dimensional particle fields in existence; however, its utility has been extremely restricted because data reduction is extremely tedious. during recent years, developments in fourier transform techniques have provided a… More

Improvements resulting from a combination of two advanced nondestructive evaluation (nde) techniques. thses are: 1) acoustic holographic imaging, and 2) digital signal processing using adaptive learning networks (aln's). each these techniques show dramatic improvements in flaw assesment over that… More

The study of particulate formation and dynamics of motion in industrial multicomponent systems has been hindered by lack of experimental data. two in-situ optical techniques are proposed here for on-line characterization of the size distribution, velocity and the number density of entrained… More

The proposed research is an investigation of a technique for making noncontract point measurements on diffusely scattering object targets at interferometric accuracies. the concept being considered is a fringe counting optical interferometer that observes the nonspecular component of diffusely… More

It is proposed that a multi-element fuel nozzle for atomization of liquid and slurry fuels be designed. the important features of the proposed nozzle are: (1)effective atomization of the fuel by generation of monodisperse droplet through each element: (2) direct control over the drop size through an… More

To certify installed multi-layer or foam insulation for future use, a nondestructive inspection technique is needed which is capable of detecting and measuring physical conditions or abnormalities which are within the insulation and cannot be obtained by visual inspection. physical conditions of… More

A technique for developing and extending the use of thermoplastic recording devices for on-line flow visualization is addressed. by combining two thermoplastic devices in such a way that independent holograms can be recorded, unique reconstruction features occur providing many benefits. this is… More

The velocity of sound in a fluid is influenced by temperature, density, and fluid velocity. the recently developed technique of ultrasonic tomography can provide a two-dimensional measurement of the ultrasonic vector velocity distribution in a plane defined by a ring of transducers enclosing the… More

This is a project to develop a pulsed laser which is specially adapted for application in a holocamera for use in wind tunnel testing. the absence of such a laser has severely restricted use of laser holography and photography in this application. specializing the laser component will provide… More

The impact of atmospheric particles on a nosetip material during reentry results in the generation of debris particles which are ejected from the crater formed. these debris particles have the potential for significantly eroding any downstream protruding surfaces such as a flare. cosequently, the… More

The measurement of the surface temperature of materials and systems during simulated reentry condition testing in hypervelocity range and track test facilities is necessary for the development of these materials and systems. temperature measuring instru mentation is not currently available to… More

A particle sizing technique that operates in conjunction with laser velocimetry is proposed. the technique uses a non-intrusive single particle counter based on a pulse height analyzer. particle size is measured from the pulse height and velocity from doppler frequency. the technique has been used… More

A particle sizing technique that operates in conjunction with laser velocimetry is proposed. the technique uses a non-intrusive single particle counter based on a pulse height analyzer. it is expected that a size range of 0.1 um to 10 um will be attainable. lower size limits would require ensemble… More

The presence of solid particulates entrained in the air can be detected by measuring their scattered light and the ov overall light extinction. very sensitive extinction m measurements can be performed with transmissometry. am amongthe most promising and simple transmissometers are the ma maximum… More

A transpiration cooled nosetip (tcnt) contains a large number of small ports distributed over its surface through which a coolant fluid is ejected. the overall objective of the proposed study is to develop a flow measurement system which will provide detailed data on the distribution of this flow… More

The presence of solid particulates entained in the air entering the engine of military vehicles can be detected by measuring their scattered light and the overall light extinction. very sensitive extinction measurements can be performed with transmissometry. among the most promising and simple… More

Significant gaps exist in the ability of current optical p particle counters to provide the information necessary to properly characterize the nature of the atmospheric particle concentrations. in particular, since spherical testparticles of known size distributions are used for ca calibration,… More

The need to develop improved signal processors to enhance the s/n of multicomponent lda systems is crucial to fundamental studies concerning helicopter and other aerodynamic bodies. although there has been a rapid development of lda techniques in the past decade, little hasbeen done to improve the… More

High voltages can be developed on materials subject to triboelectric forces. consequently, the capability of measuring the potential of hazardous sparks when charged surfaces come in contact with each other is needed. a measurement approach based on an optical fiber sensor technique which will… More

A new laser material, termed gsgg has unique properties which could prove extremely beneficial in spaceborne lidar application. efficiencies significantly higher than conventional solid state materials provide the potential of reduced weight, size and power requirement for the same energy output as… More

The probing of boundary layers, wakes, and separated flows with physical probes almost always leads to questionable results because of the interference with the flow. application of nonintrusive optical probes to make such measurements has led to important new insights in aerodyanmic flows. recent… More

A particle sizing technique that operates in conjunction with laser velocimetry (lv) is proposed. the technique uses a nonintrusive single particle counter based on the ratio of the intensity of the scattered light at two different angles. it is expected that the required size range of 0.3… More

The study of the effect of heavy rain on aircraft general performance requires knowledge of the size, velocity, and concentration of the rain drops affecting the aircraft. the program will develop and demonstrate a technique that will be used to obtain such data. the technique bases the measurement… More