A Novel Rotor Profile Generation Method for Claw-Type Vacuum Pumps Based on Sealing Line

The sealing line between two conjugated rotors is a main leakage path in the vacuum pump, however, it is unable to be adjusted before the rotor profiles are determined in the traditional rotor profile generation method. Therefore, a generation method of rotor profiles for claw-type vacuum pumps based on the sealing line is proposed in this paper. The sealing line can be firstly specified as specific segments regarding the characteristics of claw-shaped rotor profiles. By applying the enveloping theory and the cubic spline curve fitting method, the rotor profile is able to be generated from the sealing line. Moreover, the adjustment method is proposed to segmentally correct the shape of sealing line using the quadratic functions by considering the geometric limitations to avoid interference and undercutting in rotor profiles. A three-lobe claw rotors profile is carried out to demonstrate the reasonability and stability of the proposed method.

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Modeling of Thermodynamic Properties for Pure Refrigerants and Refrigerant Mixtures by Using the Helmholtz Equation of State and Cubic Spline Curve Fitting Method

Universal Journal of Mechanical Engineering ◽

10.13189/ujme.2015.030604 ◽

2015 ◽

Vol 3 (6) ◽

pp. 229-251 ◽

Cited By ~ 1

Author(s):

Halil Atalay ◽

M. Turhan Coban

Keyword(s):

Equation Of State ◽

Thermodynamic Properties ◽

Helmholtz Equation ◽

Curve Fitting ◽

Cubic Spline ◽

Spline Curve ◽

Refrigerant Mixtures ◽

Fitting Method ◽

Curve Fitting Method ◽

Cubic Spline Curve

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An additional branch free algebraic B-spline curve fitting method

The Visual Computer ◽

10.1007/s00371-010-0476-4 ◽

2010 ◽

Vol 26 (6-8) ◽

pp. 801-811 ◽

Cited By ~ 4

Author(s):

Mingxiao Hu ◽

Jieqing Feng ◽

Jianmin Zheng

Keyword(s):

Curve Fitting ◽

B Spline ◽

Spline Curve ◽

Fitting Method ◽

Additional Branch ◽

Curve Fitting Method

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Analysis on Quality Evaluation Criteria for Spline Curves

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.365-366.99 ◽

2013 ◽

Vol 365-366 ◽

pp. 99-103

Author(s):

Shi Jun Ji ◽

Ji Zhao ◽

Lei Zhang ◽

Hui Juan Yu ◽

Xiao Long Liu ◽

...

Keyword(s):

Curve Fitting ◽

Geometric Modeling ◽

Quality Evaluation ◽

Evaluation Criteria ◽

Affecting Factors ◽

Spline Curve ◽

Spline Curves ◽

Fitting Method ◽

Cad Cam ◽

Curve Fitting Method

With the development of CAD/CAM, reverse engineering, geometric modeling, animation and computer graphics. In the past fifty years, many kinds of spline curve fitting methods have been produced. But, to authors knowledge, quality evaluation criterion about different spline curves are still not established and there is a lack of a comparing standard for analyzing different spline curves. Two spline curve fitting method comparing theorem is given and several various spline curves affecting factors are analyzed in this paper. Some comparable results are obtained by using the proposed quality evaluating theorem to different spline curves.

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Sub-band denoising and spline curve fitting method for hemodynamic measurement in perfusion MRI

10.1117/12.480285 ◽

2003 ◽

Author(s):

Hong-Dun Lin ◽

Hsiao-Ling Huang ◽

Yuan-Yu Hsu ◽

Chi-Chen Chen ◽

Ing-Yi Chen ◽

...

Keyword(s):

Curve Fitting ◽

Perfusion Mri ◽

Spline Curve ◽

Fitting Method ◽

Curve Fitting Method ◽

Hemodynamic Measurement

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Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System Performance

Metrology and Measurement Systems ◽

10.2478/v10178-012-0033-8 ◽

2012 ◽

Vol 19 (2) ◽

pp. 381-394

Author(s):

José Pereira ◽

Octavian Postolache ◽

Pedro Girão

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Measurement System ◽

Curve Fitting ◽

System Performance ◽

Redox Potentials ◽

Voltage Sweep ◽

Gaussian Curve ◽

Fitting Method ◽

Curve Fitting Method

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System PerformanceThis paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.

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