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Performance of TiO2 Nanofluid and DI Water Filled Flat Type Heat Pipe (FTHP) Internally Grooved at Various Fill Ratios and Inclinations
Alagappan Narayanan,
Karunakaran Narayanaswami,
Gunabal Senthilnathan
Issue:
Volume 3, Issue 4, July 2018
Pages:
39-46
Received:
6 June 2018
Accepted:
3 July 2018
Published:
31 July 2018
Abstract: Heat pipe operates, with a metallic wick (or grooved) installed inside the pipe, containing fluid under a pressure which permits evaporated vapour at the hot side to fill the core of the pipe and travel to the cooled side. The vapour condenses at cold side, transporting heat by this method. This study focuses on the heat transfer performance of flat type internally grooved heat pipe with two different working fluids DI water and TiO2 nano fluid, used with various heat input (50, 60, 70 and 80W) and at two different orientation 45deg and 90deg of the pipe. The fill ratio used was 50% and 70%, concentration and the size of the nano particle were 80 mg/lit and 30 nm respectively. In this setup, the condenser section of the Flat Type Heat Pipe (FTHP) was cooled by rectangular aluminum fins. The result shows that the decisive factors of FTHP are the working fluids, internal grooves and inclination angle. The relatively high rate of heat transfer was achieved while using TiO2 nano fluid at 90deg orientation with a fill ratio of 50% compared to FTHP with DI water.
Abstract: Heat pipe operates, with a metallic wick (or grooved) installed inside the pipe, containing fluid under a pressure which permits evaporated vapour at the hot side to fill the core of the pipe and travel to the cooled side. The vapour condenses at cold side, transporting heat by this method. This study focuses on the heat transfer performance of fla...
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A Multiaxial Variable Amplitude Fatigue Life Prediction Method Based on a Plane Per Plane Damage Assessment
Bianzeube Tikri,
Fabienne Fennec,
Bastien Weber,
Jean-Louis Robert
Issue:
Volume 3, Issue 4, July 2018
Pages:
47-54
Received:
23 June 2018
Accepted:
19 July 2018
Published:
17 August 2018
Abstract: A multiaxial variable amplitude fatigue life prediction method is proposed in this paper. Three main steps are distinguished. The first one concerns the counting of multiaxial cycles and uses the normal stress to a physical plane as the counting parameter. Then a multiaxial finite fatigue life criterion allows one to assess the material life corresponding to each cycle on any physical plane. A damage law and its cumulation rule describe the damage induced by each cycle plane per plane. By this way the critical plane for a given multiaxial stress history is found out. It is assumed to be the fracture plane and the fatigue life of the material is traduced as the number of repetitions of the sequence up to crack initiation. At this stage, material fatigue criteria and linear and nonlinear damage laws assume that the material is damaged. One distinguishes among these criteria critical plan type whose formalism can identify the crack initiation plan. An application is given for each load. In the context of multiaxial solicitations of variable amplitude, a validation of the estimation of the orientations of the priming planes is carried out based on experimental results on cruciform test pieces; the estimated orientations are close to those observed experimentally.
Abstract: A multiaxial variable amplitude fatigue life prediction method is proposed in this paper. Three main steps are distinguished. The first one concerns the counting of multiaxial cycles and uses the normal stress to a physical plane as the counting parameter. Then a multiaxial finite fatigue life criterion allows one to assess the material life corres...
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Analysis of Vibration and Sound Radiation Characteristics of Resilient Wheel in Metro
Jianhui Tian,
Ke Wang,
Kan Xiao
Issue:
Volume 3, Issue 4, July 2018
Pages:
55-63
Received:
17 July 2018
Accepted:
6 August 2018
Published:
15 September 2018
Abstract: The wheel of vehicles is not pure rolling on the rail for the track irregularity, but with a small vertical and horizontal relative displacement. The relative displacement produces the wheel rail force and causes the vibration of the wheel and rail, which is transmitted to the air and produces noise. Therefore, it is of great significance to study the wheel's vibration and sound radiation under the track irregularity conditions. In this paper, the wheel-rail coupling dynamic analysis model of metro vehicle was established by using UM software and was researched by numerical calculation method, the wheel-rail contact force under irregularity excitation was obtained. Then the acoustic calculation model of the rigid wheel and the resilient wheel was established. Combined with the structural finite element method and the acoustic boundary element method, the structural response obtained by transient dynamic analysis was used as the boundary condition to study the acoustic radiation characteristics and the noise reduction effect of the resilient wheel. The study results show that under the vertical excitation of wheel-rail, compared with rigid wheel, the use of resilient wheel can inhibit the vibration for rim, tread and web. The vibration acceleration attenuation of the web is most significant, from 97m/s2 to 58m/s2. It is because of the vibration reduction function of the rubber body for the resilient wheel. The sound power level of the resilient wheel has a slight increase in the low frequency range and has a slight decrease in the high frequency range, in the whole calculated frequency range the sound power level of the resilient wheel decreases by 10.1 dB. These provide a good reference for the resilient wheel application in metro vehicle.
Abstract: The wheel of vehicles is not pure rolling on the rail for the track irregularity, but with a small vertical and horizontal relative displacement. The relative displacement produces the wheel rail force and causes the vibration of the wheel and rail, which is transmitted to the air and produces noise. Therefore, it is of great significance to study ...
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Modal Analysis of L Type Compressor Crankshaft
Xiaoyan Niu,
Cong Chen,
Linlin Shen,
Erzhong Chen
Issue:
Volume 3, Issue 4, July 2018
Pages:
64-70
Received:
27 August 2018
Accepted:
11 September 2018
Published:
11 October 2018
Abstract: Reciprocating compressor is an important equipment in industrial production. The crankshaft turns the thrust of the compressor piston rod into torque, which is an important component of the compressor. When reciprocating compressor works, there will be various forms of vibration such as torsion and bending. Therefore, the study of the crankshaft vibration becomes particularly important. Analyze the modal analysis of L type compressor crankshaft by using the finite element simulation. The first six order natural frequency and the corresponding mode of vibration of the crankshaft are obtained. And analyze the influence of the hollow and solid on the natural frequency and mode of vibration of the crankshaft. The results show: With the increase of vibration order, the natural frequency of the crankshaft increase. The crankshaft deformation is mainly bending at low frequency. The deformation of crankshaft is mainly composed of bending and torsional vibration at higher frequency. Moreover, the ends of solid crankshafts are less restrained. Extend the service life and performance of the crankshaft and other parts of the compressor by increasing the strength and stiffness of the crankshaft's local materials. And increasing the fillet radius at the transition point are adopted to reduce the deformation and torsion of the crankshaft.
Abstract: Reciprocating compressor is an important equipment in industrial production. The crankshaft turns the thrust of the compressor piston rod into torque, which is an important component of the compressor. When reciprocating compressor works, there will be various forms of vibration such as torsion and bending. Therefore, the study of the crankshaft vi...
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