Numerical Simulation of Interaction between Supersonic Flow and Backward Inclined Jets Surrounded by Porous Cavity

As one of supersonic mixing techniques, a supersonic mixing technique using a cavity and a porous wall has been proposed. The cavity and the porous wall generate the low speed region in the cavity, which enhances mixing the main flow with the jets. In this study, numerical simulations were conducted to clarify the effects of backward inclined jets on the mixing technique using a porous wall and a cavity. In the numerical simulations, three patterns of jet injections which combined normal jets with backward inclined jets were studied. As a result, the combination of a backward inclined jet and a normal jet generates the suction flow behind the backward inclined jet, which is useful for making the injected jets flow into the cavity. In addition, the introduction of backward inclined jets reduces the total pressure loss. On the other hand, the mass flow rate through the porous holes decreases with increase in the number of the backward inclined jets.

NiFe alloy particles doping effect of Gd-Ba-Cu-O bulks processed by a new cold-seeding technology

The process of cold seeding melt growth of GdBa2Cu3Oy （Gd123） bulk superconductors using NdBa2Cu3Oy （Nd123） thin films was reported. In addition, a novel cold seeding concept of combining MgO crystal and buffer pellet was also introduced. The misorientation caused by the lattice mismatch between MgO and Gd123 melt was overcome by choosing suitable heat treatment program and Gd2BaCuO5 （Gd211） content of the buffer pellet. The doping effect of soft ferromagnetic NiFe alloy particles was also reported. The bulk sample with 0.4% （mole fraction） doping amount shows the best performance on the flux trapping. The critical current density is largely enhanced under the external field of 1-2 T, which is promising for large-scale applications. This effect is originated from the substitution of Fe and Ni ions for the Cu sites contributing to magnetic flux pinning.

Toyota’s Slow Response to Manufacturing Defects Leading to Recalls: Result of Poor Communication Strategy

The recall of vehicles in the automobile industry is not limited to any particular company. Recalls most often have been attributed to defective parts supplied by tier one and tier two suppliers. Toyota, a world leader in the manufacture of automobiles, built on world class corporate brand and Principles known as the Toyota Way, and located in about 53 countries in the world, with most of its production taking place in the North America and Japan. Its Communication strategy leading to recalls has brought it into conflict with its customers and regulatory agencies. Toyota’s seeming departure from its core principles in the Toyota Way has also brought it into conflict with suppliers and affected its production. Answers will be sought for the following research questions: 1) Why with its Toyota Way, Communication became a challenge for Toyota? 2) What is the role of the Media, in Toyota’s issues of recall? A detailed literature survey was conducted for Toyota’s communication strategy. A dialectic inquiry was used to analyse the acquired data, from interviews conducted.

Bubble Size Measurement by the Ultrasonic Pulse Echo with Tracking Technique

Bubbly flows appear in many different industrial fields and the measurement of bubble sizes is crucial for understanding phase interactions. The ultrasound pulse echo can be used for a non-intrusive measurement of the bubble surface position in one dimension even when there is no optical access to the bubble. A simultaneous measurement from two opposing directions gives the bubble size but has been performed only on single bubbles. This work applies the tracking technique, which allows a simultaneous measurement of multiple bubbles. The performance of the bubble size measurement was tested experimentally by comparing ultrasonic results with the sizes measured by a high-speed camera and also with metal cylinders. Possible sources of measurement uncertainty were analysed and discussed. The tested range of bubble sizes was up to 10 mm and the void fraction was lower than 1.25%.