Transducer applications, a compilation

The characteristics and applications of transducers are discussed. Subjects presented are: (1) thermal measurements, (2) liquid level and fluid flow measurements, (3) pressure transducers, (4) stress-strain measurements, (5) acceleration and velocity measurements, (6) displacement and angular rotation, and (7) transducer test and calibration methods

The Surface Topography of a Magnetic Fluid -- a Quantitative Comparison between Experiment and Numerical Simulation

The normal field instability in magnetic liquids is investigated experimentally by means of a radioscopic technique which allows a precise measurement of the surface topography. The dependence of the topography on the magnetic field is compared to results obtained by numerical simulations via the finite element method. Quantitative agreement has been found for the critical field of the instability, the scaling of the pattern amplitude and the detailed shape of the magnetic spikes. The fundamental Fourier mode approximates the shape to within 10% accuracy for a range of up to 40% of the bifurcation parameter of this subcritical bifurcation. The measured control parameter dependence of the wavenumber differs qualitatively from analytical predictions obtained by minimization of the free energy.Comment: 21 pages, 16 figures; corrected typos, added reference to Kuznetsov and Spector(1976), S.J. Fortune(1995) and Harkins&Jordan (1930). Figures revise

Techniques for mounting an ultrasonic temperature device Final report

Transducer mounting technique for applying ultrasonic method of temperature measurement to rocket thrust chamber

Laser‐driven strong‐field Terahertz sources

A review on the recent development of intense laser‐driven terahertz (THz) sources is provided here. The technologies discussed include various types of sources based on optical rectification (OR), spintronic emitters, and laser‐filament‐induced plasma. The emphasis is on OR using pump pulses with tilted intensity front. Illustrative examples of newly emerging applications are briefly discussed, in particular strong‐field THz control of materials and acceleration and manipulation of charged particles

A feasibility study on determination of the deviation from level utilizing optical interference created by a laser source

Feasibility of determining deviations from level by laser source optical interferenc

F-14 VSTFE and results of the cleanup flight test program

Flight transition data applicable to swept wings at high subsonic speeds are needed to make valid assessments of the potential for natural laminar flow or laminar flow control for transports of various sizes at various cruise speeds. NASA initiated the variable sweep transition flight experiment (VSTFE) to help establish a boundary layer transition data base for use in laminar flow wing design. The carrier vehicle for this experiment is an F-14, which has variable sweep capability. The variable sweep outer panels of the F-14 were modified with natural laminar flow gloves to provide not only smooth surfaces but also airfoils that can produce a wide range of pressure distributions for which transition location can be determined. The VSTFE program is briefly described and some preliminary glove I flight results are presented

A Method of Embedding Accelerometers in Solid Rocket Motors

The USAF MINUTEMAN ICBM Transportation and Handling Test Program involves vibration testing of full scale motors. A major problem in vibration testing of large solid propellant motors is developing a method of embedding accelerometers in the viscoelastic propellant. The accelerometers are needed to determine experimentally the dynamic response of the propellant during the environmental tests, and to verify the motor\u27s dynamic analysis. The engineering analyses and experimental tests employed by Thiokol Chemical Corporation to develop the accelerometer installation method is the subject of this paper. The results of the instrumentation, and the degree to which the desired results were achieved, are discussed. Extensive engineering studies were made to determine the minimum number, location, and type of accelerometers required to describe the dynamic response of the propellant. A technique was developed for controlling the position and orientation of the accelerometers when embedded in the motor propellant. A laboratory research program was conducted to develop reliable bond joints