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Analyzing Vibration Suppression of Nuclear Power Crane with Model Coupling Mechanism and Structure
Yixiao Qin,
Qingqing Yang,
Yanqing Li,
Cuiyun Gu
Issue:
Volume 4, Issue 4, August 2016
Pages:
136-142
Received:
24 May 2016
Accepted:
5 June 2016
Published:
18 June 2016
Abstract: The nuclear power crane possesses strict safety requirements. Based on the special structure of its hoisting mechanism, it has two sets of independent lifting ropes to drive a hook synchronously and two pressure buffer devices on both ends of winding system’s balancing lever, in order to play protective roles and increase its working reliability. The flexible multi-body dynamics model which coupled mechanism and structure of the nuclear power crane is constructed when broken accident of rope occurs in the lifting process from the ground or smooth lifting. The importance of a buffer damping device installed in crane hoist mechanism has been proved through the vibration simulation about wire rope at the failure state. And the vibration of mechanism and the main girder structure is remitted and controlled at the time of failure in operation. The most important advantage is that has improved the safety of nuclear power crane.
Abstract: The nuclear power crane possesses strict safety requirements. Based on the special structure of its hoisting mechanism, it has two sets of independent lifting ropes to drive a hook synchronously and two pressure buffer devices on both ends of winding system’s balancing lever, in order to play protective roles and increase its working reliability. T...
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Aerodynamic and Stability Analysis of Blended Wing Body Aircraft
Sanjiv Paudel,
Shailendra Rana,
Saugat Ghimire,
Kshitiz Kumar Subedi,
Sudip Bhattrai
Issue:
Volume 4, Issue 4, August 2016
Pages:
143-151
Received:
17 May 2016
Accepted:
12 June 2016
Published:
23 June 2016
Abstract: The main purpose of the paper is to study the aerodynamic and stability characteristics of a blended-wing-body (BWB) aircraft. This paper presents the estimation and selection of aircraft design parameters, planform design, reflex airfoils, and conduct thorough stability investigation of the aircraft. A conceptual design of BWB aircraft has been done and the design was analyzed and refined to achieve static stability. The CFD analysis of the BWB aircraft was done at three different values of angle-of-attack (AOA) and thus the stall AOA was determined from the computational results. The dynamic stability of the aircraft has been studied under five modes namely- short period, phugoid, Dutch-roll, roll and spiral. The static stability has been achieved with a wide positive value of static margin. Results also show that the aircraft is dynamically stable for longitudinal and lateral modes when subjected to disturbances in respective conditions. The BWB aircraft fulfils the criteria of Class I Category B aircraft and shows flight level 1 characteristics in all stability modes.
Abstract: The main purpose of the paper is to study the aerodynamic and stability characteristics of a blended-wing-body (BWB) aircraft. This paper presents the estimation and selection of aircraft design parameters, planform design, reflex airfoils, and conduct thorough stability investigation of the aircraft. A conceptual design of BWB aircraft has been do...
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Simulation Research on Airflow Field of Bulldozer Cab
Zhu Jian,
Ren Hongjuan,
Luo Yiping
Issue:
Volume 4, Issue 4, August 2016
Pages:
152-155
Received:
20 June 2016
Accepted:
30 June 2016
Published:
23 July 2016
Abstract: This paper used the airflow organizations of a bulldozer cab as the research object, and the physical model and mathematical model of the three-dimensional airflow is played, and computational fluid dynamic software FLUENT is used to simulate the airflow organizations. The governing equations were solved by using the RNGk- ε two equation turbulence model and SIMPLE algorithm. We obtained the simulation results of temperature field and velocity field distribution of different air-supply modes in the driving room of the bulldozer in summer. The results show airflow distribution by different types of air-supply of the air conditioning of the bulldozer cab, which provides a theoretical basis to improve the thermal environment, and it has guiding function to the design of air duct of the engineering vehicle.
Abstract: This paper used the airflow organizations of a bulldozer cab as the research object, and the physical model and mathematical model of the three-dimensional airflow is played, and computational fluid dynamic software FLUENT is used to simulate the airflow organizations. The governing equations were solved by using the RNGk- ε two equation tu...
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Research on Abnormal Noise Evaluation Method of Window Lift Motor Based on Subjective and Objective Psychoacoustics
Yi Zikui,
Tan Jianping,
Yan Tao,
Liu Sisi
Issue:
Volume 4, Issue 4, August 2016
Pages:
156-165
Received:
2 August 2016
Published:
8 August 2016
Abstract: To overcome the weakness of the existing noise evaluation method for the window lift motor, a kind of abnormal noise evaluation method based on objective psycho acoustic metrics is proposed. As the existing objective psycho acoustic metrics cannot be fully applicable to the window lift motor noise evaluation, based on the sharpness of the Zwicker model, a weighting factor similar to the window function used to modify the sharpness is proposed according to the characteristic of the window lift motor noise. The effectiveness of the objective metrics on the subjective perception is analysed by consistency experiment of the subjective and objective evaluation of the window lift motor noise. The results show that the loudness and modified sharpness have strong correlation with the subjective evaluation results and can accurately reflect the subjective feelings of people. So they can be used for window lift motor noise classification and evaluation.
Abstract: To overcome the weakness of the existing noise evaluation method for the window lift motor, a kind of abnormal noise evaluation method based on objective psycho acoustic metrics is proposed. As the existing objective psycho acoustic metrics cannot be fully applicable to the window lift motor noise evaluation, based on the sharpness of the Zwicker m...
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