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Elastocaloric cooling has no environmental effects during operation, and achieving a compact structure especially the driver is significant for its commercialization. In this article, a compact, standalone crankshaft driven single long NiTi tube compressive elastocaloric cooler is developed. A crankshaft driver was designed and fabricated to drive a compressive elastocaloric regenerator utilizing a single long polycrystalline superelastic NiTi shape memory alloy tube (outer diameter 5 mm, wall thickness 1 mm, and initial length 305 mm). A novel design of ceramic heat insulation plate was applied to the cooler to reduce the conduction heat loss from the NiTi tube to the stainless-steel loading heads. The cooling performance of the cooler was characterized using synchronized thermocouples and infrared thermography, and the specific cooling(heating) power, temperature span, and coefficient of performance of up to 65(125) W·kg−1, 9.1 K, and 5.0, respectively were measured. The progressions of the temperature span, specific cooling(heating) power, and coefficient of performance with the operation cycle and temperature lift were analyzed. An energy analysis revealed that the heat transfer fluid carried out only 14% of the latent heat generated by the NiTi tube, which demonstrated a potential to enhance the cooling performance by the improvement in the regenerator structure. [ABSTRACT FROM AUTHOR]

Five group of different layering methods of basalt/carbon fiber (BF/CF) hybrid reinforced resin matrix composites are prepared by vacuum infiltration hot-press forming process. The bending properties with different layering methods have obvious distinguishing, B5C1 (B-Basalt fiber, C-Carbon fiber) has the lowest bending strength of 283 MPa, and B1C5 has the highest bending strength of 404 MPa. The observation of microstructure shows that infiltration effect of composites is good, and matrix is fully and evenly distributed in fibers. The bending fracture morphology is also relatively ideal. Some of the fibers show brittle fracture morphology and others show pull-out morphology, further indicating that the fibers are tightly bound to the matrix. In addition, the ultimate bending strength of composite single-layer plate is calculated, and the formula for calculating the bending strength of the composite laminate is established based on the laminate principle. By modifying the calculation formula, more accurate results are obtained. The experimental results are in good agreement with the theoretical ones, and the reliability of the calculation method is verified. The results showed that carbon fiber enhanced the bending strength of hybrid laminates, but with the increase of carbon fiber content, the strengthening effect decreased [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced shape memory polymer composite (SMPC) is a kind of smart material with shape memory characteristics, which is widely used in aerospace, biomedicine, robotics and other fields. In this paper, SMPC was prepared by heating molding process at five different molding temperatures. The effect of molding temperature on the shape memory performance of SMPC was studied. The results show that the shape memory properties of SMPC are closely related to the infiltration effect during the preparation process. When the molding temperature is 70 °C, SMPC has an optimum penetration effect and the preparation defects are effectively controlled. The shape fixing rate is 84.3%, and the shape recovery rate is 94.7%, which lays a foundation for the better application of shape memory composite. [ABSTRACT FROM AUTHOR]

Micro liquid dispensing technology is widely used in the field of electronic packaging. This study presents a lumped parameter model of a needle-type piezostack-driven jetting dispenser, which can produce small high viscosity adhesive droplets with a high driving frequency. After describing the structural components and operating principles of the dispenser, a lumped parameter model for the system is derived by integrating the sub-models of the structural and fluid parts. According to the lumped parameter method, the fluid channels of the dispenser have been divided into several lumps to obtain a more accurate performance. Based on the proposed model, the jetting dispenser is designed and manufactured, and its performance is then evaluated through both computer simulations and experiments. Further experimental studies about its working properties based on the proposed dispenser are carried out. The results are used to guide the design and control works about the proposed dispenser. [ABSTRACT FROM PUBLISHER]