Westinghouse Electric

About: Westinghouse Electric is a company organization based out in Cranberry Township, Pennsylvania, United States. It is known for research contribution in the topics: Brake & Signal. The organization has 27959 authors who have published 38036 publications receiving 523387 citations.

Study of creep behavior of ultra‐high‐molecular‐weight polyethylene systems

Abstract: The short- and long-term creep behaviors of ultra-high-molecular-weight polyethylene (UHMWPE) systems (compression-molded UHMWPE sheets and self-reinforced UHMWPE composites) have been investigated. The short-term (30-120 min) creep experiment was conducted at a load of 1 MPa and a temperature range of 37-62 degrees C. Based on short-term creep data, the long-term creep behavior of UHMWPE systems at 1 MPa and 37 degrees C was predicted using time-temperature superposition and analytical formulas. Compared to actual long-term creep experiments of up to 110 days, the predicted creep values were found to well describe the creep properties of the materials. The creep behaviors of the UHMWPE systems were then evaluated for a creep time of longer than 10 years, and it was found that most creep deformation occurs in the early periods. The shift factors associated with time-temperature superposition were found to increase with increasing temperature, as per the Arrhenius equation. The effects of temperature, materials, and load on the shift factors could be explained by the classical free volume theory.

Optical switching characteristics of epitaxial bismuth titanate films for matrix-addressed displays

Abstract: Electro-optic switching properties of (010) epitaxial Bi4Ti3O12 films grown on (110) MgAl2O4 substrates have been investigated. The measurements were carried out on large-area films in situ on the spinel substrate using an inter-digitated electrode array. A contrast ratio higher than 7:1 was obtained. Switching times of less than 5 μsec were measured at fields >60 kV/cm. Due to substrate clamping the field needed for switching the epitaxial film was about seven times higher than that for bulk single crystal at a same switching speed. The films exhibit an apparent switching threshold and grey scale capability. Finally, an experimental X-Y matrix-addressed display has been designed and evaluated.

Apparatus and method for providing a combined ultrasonic and eddy current inspection of a tube

Abstract: Both an apparatus and a method for simultaneously inspecting the walls of a tube with both ultrasonic and eddy current probes is disclosed herein. The apparatus generally comprises a cylindrical housing assembly insertable within the tube to be inspected, and a probe carrier rotatably mounted within and helically movable with respect to the housing. The probe carrier holds three ultrasonic probes for transmitting ultrasonic beams which are directly oriented radially, chordally, an axially with respect to the longitudinal axis of the tube, as well as an eddy current probe for simultaneously inspecting the walls of the tube with electromagnetic lines of flux. The apparatus further includes a helical drive train formed from a lead screw assembly having a motor means, a drive shaft, and a drive sleeve for imparting a helical scanning motion to the probe carrier with respect to the housing. The interior of the drive sleeve is slidably engaged to the shaft which is in turn coupled to the output of the motor, while the outside of the drive sleeve is threadedly engaged to the interior of the housing. The probe carrier is in turn coupled to the drive sleeve. In the method of the invention, the data generated by the three eddy current probes is correlated with the data generated by the eddy current probe for each specific section of the tube, and displayed simultaneously to the system operator. The resulting complementary display of both ultrasonic and eddy current probe information allows the system operator to accurately determine the size, shape and nature of any flaws which may be present in the walls of the tube.

A comparison of the daphnids Ceriodaphnia dubia and Daphnia ambigua for their utilization in routine toxicity testing in the Southeastern United States.

Abstract: U.S. regulatory agencies commonly require effluent toxicity testing with Ceriodaphnia dubia—a practice that has led to the criticism that this species and test protocol often does not reflect local taxa or site-specific conditions. Using an indigenous test species may produce a more realistic model of local effects and may minimize test endpoint variance due to regional differences in water quality. This study addressed the substitution of C. dubia with Daphnia ambigua for toxicity testing in the southeastern United States. This investigation determined that D. ambigua could be laboratory cultured with only minimal changes to established regulatory protocol and that the life-cycle characteristics of this species were conducive to traditional acute and chronic aquatic toxicity test methods used with other daphnids. Acute toxicity tests showed that D. ambigua was less sensitive to some toxicants (sodium chloride, copper sulfate, and sodium lauryl sulfate) but more sensitive to others (chlorpyrifos). Chronic tests with copper sulfate and sodium chloride resulted in lower EC50s for D. ambigua reproduction with both compounds. When exposed to low-alkalinity, low-pH stream waters typical of many southeastern United States watersheds, C. dubia demonstrated a significant reproductive depression in two of three streams tested, whereas D. ambigua experienced no chronic effect. These results suggest that D. ambigua may serve as a suitable surrogate for C. dubia as an toxicity indicator species in these types of receiving streams.

Temperature-dependent heat sources or sinks in a stagnation point flow

Abstract: An analytical study has been made to determine the heat transfer characteristics of a stagnation point flow in which there are temperature-dependent heat sources or sinks. Results have been obtained for both strong and weak sources or sinks for a Prandtl number of 0.7. An analytical method, applicable to all Prandtl numbers, was utilized which circumvented the need for extensive numerical solutions and which, at the same time, provided a closed-form representation for the heat transfer. A few numerical solutions were carried out to verify the method.