A new PvT device for high performance thermoplastics: Heat transfer analysis and crystallization kinetics identification

Abstract This work investigates the possibility of using polyetherimide (PEI) as an energy saving alternative to glass, polymethylmethacrylate (PMMA) and polycarbonate (PC) by carrying out heat transfer analysis and suggests vaporized solvent bonding as a viable bonding technique for the fabrication of PEI. By heat transfer analysis using building energy simulation, it is observed that less energy is expended for space-conditioning of a building with windows made of PEI when compared to glass, PMMA and PC. The compression moulding technique is used to mould PEI and fabrication is done using a solvent mixture of dimethyl sulfoxide and tetrahydrofuran in 1:1 ratio. The optical properties of the bonded specimen are studied using UV-visible spectrophotometry and it is found that PEI does not allow UV wavelength radiation to pass through while transmitting visible wavelengths. The mechanical strength of the bond is tested using lap shear tensile strength test and the type of failure is observed to be cohesive from the structure. This is indicative of the fact that using this particular solvent to bond PEI results in the maximum possible strength.

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Conjugate Heat Transfer Analysis of a Cooled Turbine Blade Using Frozen Rotor Approach

Volume 5A: Heat Transfer ◽

10.1115/gt2015-43699 ◽

2015 ◽

Cited By ~ 1

Author(s):

Kuo-San Ho ◽

Jong Liu ◽

Christopher Urwiller ◽

S. Murthy Konan ◽

Bruno Aguilar

Keyword(s):

Heat Transfer ◽

Gas Turbines ◽

High Performance ◽

Conjugate Heat Transfer ◽

Cfd Simulation ◽

Heat Transfer Analysis ◽

Research Papers ◽

Ansys Cfx ◽

Computational Fluid Dynamics Cfd ◽

Maximum Temperatures

In recent years, conjugate heat transfer (CHT) computational fluid dynamics (CFD) simulation in turbomachinery played an important role in predicting metal temperature. Most of research papers of CHT CFD simulation were emphasized on the mixing plane method. In this paper the ANSYS CFX 14.0 CHT simulation using the frozen rotor approach is employed to predict the blade temperatures. The frozen rotor included five time instances in which the stator-rotor wake influence could be captured. In this study, the temperature predictions using the frozen rotor approach were compared to the mixing plane predictions and Silicon Carbide (SiC) chip measurements on three different radial spans. The frozen rotor results predicted the minimum and maximum temperatures that bounded the SiC chip data. Compared to the mixing plane predictions, the frozen rotor approach results were similar within 8 K at the mid-span. However, the frozen rotor approach provided more insight information and detailed guidance for model calibration. Finally several future works were suggested to continue striving for high performance gas turbines.

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Design, analysis, and performance verification of a water jet thruster for amphibious jumping robot

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406219844529 ◽

2019 ◽

Vol 233 (15) ◽

pp. 5431-5447 ◽

Cited By ~ 1

Author(s):

Jixue Mo ◽

Zhihuai Miao ◽

Bing Li ◽

Yunlu Zhang ◽

Zhendong Song

Keyword(s):

Heat Transfer ◽

Liquid Nitrogen ◽

High Performance ◽

Volume Fraction ◽

Water Jet ◽

Heat Transfer Analysis ◽

Underwater Robots ◽

Ansys Fluent ◽

Jumping Robot ◽

Dynamics Simulations

In nature, certain aquatic animals and seabirds are capable of leaping from water surface and overcoming aquatic obstacles with ease. Inspired by that, researchers have developed various underwater robots, which can perform the aquatic jumping motion. Although there are several ways to achieve it, the water jet propulsion is the most appropriate approach for the amphibious jumping robot, which is under development. In this paper, a high-performance water jet thruster powered by liquid nitrogen is proposed to be the potential actuator for the amphibious jumping robot. The theoretical jumping model is built to optimize the initial volume fraction of water inside thruster and analyze its parameters' variation during water jet. Then the computational fluid dynamics simulations by ANSYS FLUENT software are carried out to analyze the self-pressurization process of liquid nitrogen as well as the water jet process. Finally, the proof-of-concept outdoor experiments present that the 3.7 kg thruster's maximum aquatic and terrestrial jumping heights are 25.1 m and 24.4 m, respectively. A simple heat transfer analysis between water and liquid nitrogen is also conducted, and the order of magnitude estimation of heat transfer coefficient is given to be 265W/ (m2·K) based on the experimental reaction time.

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