A General Mathematical Model for Gears Cut by CNC Hobbing Machines

1997 ◽  
Vol 119 (1) ◽  
pp. 108-113 ◽  
Author(s):  
Shinn-Liang Chang ◽  
Chung-Biau Tsay ◽  
Shigeyoshi Nagata
Keyword(s):  
Mathematical Model ◽  
Degree Of Freedom ◽  
Cutting Process ◽  
Generation Process ◽  
Cutting Mechanism ◽  
Gear Cutting ◽  
Different Types ◽  
General Mathematical Model ◽  
Crossed Axes ◽  
The Mathematical Model

A hobbing machine’s cutting mechanism is a mechanism with multi-degree of freedom during the cutting process. In this paper, we propose a general gear mathematical model simulating the generation process of a 6-axis CNC hobbing machine based on the cutting mechanism of CNC hobbing machine and worm-type hob cutter. The proposed gear mathematical model can be applied to simulate different types of gear cutting. Some examples are included to verify the mathematical model. Also, a novel type of gear named “Helipoid” which can be used in crossed axes transmission is proposed. The proposed general gear mathematical model can facilitate a more thorough understanding of generation processes and toward the development of novel types of gears.

An enhanced composting process with bioaugmentation: Mathematical modelling and process optimization

2021 ◽  
pp. 0734242X2110337
Author(s):  
Tea Sokač ◽  
Anita Šalić ◽  
Dajana Kučić Grgić ◽  
Monika Šabić Runjavec ◽  
Marijana Vidaković ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Model Simulation ◽  
Process Conditions ◽  
Air Flow Rate ◽  
Optimal Process ◽  
Composting Process ◽  
Different Types ◽  
Adiabatic Reactor ◽  
The Mathematical Model ◽  
Good Agreement

In this paper, two different types of biowaste composting processes were carried out – composting without and with bioaugmentation. All experiments were performed in an adiabatic reactor for 14 days. Composting enhanced with bioaugmentation was the better choice because the thermophilic phase was achieved earlier, making the composting time shorter. Additionally, a higher conversion of substrate (amount of substrate consumed) was also noticed in the process enhanced by bioaugmentation. A mathematical model was developed and process parameters were estimated in order to optimize the composting process. Based on good agreement between experimental data and the mathematical model simulation results, a three-level-four-factor Box-Behnken experimental design was employed to define the optimal process conditions for further studies. It was found that the air flow rate and the mass fraction of the substrate have the most significant effect on the composting process. An improvement of the composting process was achieved after altering the mentioned variables, resulting in shorter composting time and higher conversion of the substrate.

Rim Sealing of Rotor-Stator Wheelspaces in the Absence of External Flow

1991 ◽  
Author(s):  
J. W. Chew ◽  
S. Dadkhah ◽  
A. B. Turner
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Reynolds Numbers ◽  
External Flow ◽  
Rotating Disc ◽  
Different Types ◽  
The Mathematical Model

Sealing of the cavity formed between a rotating disc and a stator in the absence of a forced external flow is considered. In these circumstances the pumping action of the rotating disc may draw fluid into the cavity through the rim seal. Minimum cavity throughflow rates required to prevent such ingress are estimated experimentally and from a mathematical model. The results are compared with other workers’ measurements. Measurements for three different types of rim seal are reported for a range of seal clearances and for rotational Reynolds numbers up to 3 × 106. The mathematical model is found to correlate the experimental data reasonably well.

Chaotic Phenomena Induced by the Fast Plastic Deformation of Metals During Cutting

2005 ◽  
Vol 73 (2) ◽  
pp. 240-245 ◽  
Author(s):  
Zoltan Palmai
Keyword(s):  
Mathematical Model ◽  
Plastic Deformation ◽  
Shear Stress ◽  
General Structure ◽  
Equation System ◽  
Qualitative Description ◽  
Balance Equations ◽  
Different Types ◽  
Energy Equations ◽  
The Mathematical Model

In the present study the examination of chip formation is focused on the primary shear zone, which is divided into two layers, and the variation of shear stress and temperature in time are given by two mechanical balance equations and three energy equations. All the five evolution differential equations are autonomous and nonlinear. The material characteristics are determined by an exponential constitutive equation. The mathematical model is suitable for the qualitative description of different types of chips, such as continuous chips and periodic or aperiodic shear localized chips, which is demonstrated by the general structure and typical solutions of the equation system.

scholarly journals DEVELOPMENT OF A MATHEMATICAL MODEL FOR THE RESEARCH OF THE DYNAMICS OF VIBRATION MILL WITH TWO DRIVES FOR BULK MATERIALS FINE GRINDING

2021 ◽  
pp. 89-99
Author(s):  
Volodymyr Topilnytskyy ◽  
Dariya Rebot
Keyword(s):  
Mathematical Model ◽  
Optimal Designs ◽  
High Tech ◽  
Bulk Materials ◽  
Fine Grinding ◽  
Different Types ◽  
Parameterized Model ◽  
The Mathematical Model ◽  
Universal Equipment ◽  
Vibration Mill

Reducing by grinding the size of various materials as raw materials for its further use is an urgent applied task. The requirements for the final product obtained by fine grinding are its homogeneity in shape and size of individual parts. It is necessary to reduce the time of the grinding operation, reduce energy consumption to obtain a unit of product of the required quality. One way to solve the problem is to use high-tech universal equipment, namely mills for fine grinding of materials. One way to solve the given problem is to use high-tech universal equipment, namely mills for fine grinding of materials. Their optimal design, construction, manufacture and operation are ensured by studying their dynamics at the stage of their development. In particular, such a study of the dynamics can be carried out on the basis of previously created mathematical models of these mills. The use of computer technology and appropriate mathematical CAD systems will speed up and optimize the process of studying the dynamics of the corresponding mill of fine grinding of materials. The purpose of the research is to build a mathematical nonlinear parameterized model of vibrating mill with two drives for bulk materials fine grinding for further study on its basis the dynamics of the mill with the development of optimal designs for mills with similar structure and the principle of operation and selection of optimal modes of operation. The mathematical model is presented as a system of expressions describing the of the mill points motion, which will include in the form of symbolic symbols all its parameters (kinematic, geometric, dynamic, force). This model is constructed using the Lagrange equation of the second kind and asymptotic methods of nonlinear mechanics. The mathematical model for studying of the dynamics of vibration mill with two drives for bulk materials fine grinding is nonlinear and universal. The non linearity of the model makes it possible to adequately determine of the above parameters influence on the amplitude of oscillations of the mill working chamber as the main factor in the intensity in the technological process of the fine grinding bulk materials fine grinding. The possibility of a wide range of changes in the parameters of the mill in the obtained models makes it universal based on the possibility of application for the study of dynamic processes in vibrating mills of different types with two or one drive which are different by shape, size, location of the suspension and more. This model can also be used to develop optimal designs for vibrating mills for different industries, which will be used to grind different types of materials in different volumes and productivity.

scholarly journals Simulation Analysis of One Degree of Freedom Motion of Electromagnetic Spherical Joint based on Maxwell

2021 ◽  
Vol 2085 (1) ◽  
pp. 012014
Author(s):  
Haoran Wang ◽  
Fucong Liu ◽  
Sai Lou
Keyword(s):  
Mathematical Model ◽  
Simulation Analysis ◽  
Lagrange Equation ◽  
Degree Of Freedom ◽  
Spherical Joint ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Structure And Motion ◽  
The Mathematical Model ◽  
The Relationship

Abstract In order to improve the stiffness of the spherical joint of the robot, reduce the difficulty of manufacturing and the complexity of the control system, this paper proposed a method of spherical joint and digital drive of the robot based on the electromagnetic principle. Firstly, introduces the structure and motion principle of the spherical joint of the robot, establishes the mathematical model of the spherical joint and establishes the dynamic model according to the second Lagrange equation. after that, the relationship between the number of ampire-turns of the electromagnet on the spherical joint, the attitude Angle of the rotor and the force of the rotor was obtained by simulating the single degree of freedom of the joint based on Ansys maxwell and Matlab, which provided a basis for the realization of the digital drive of the spherical joint.

scholarly journals Validation of friction factor predictions in vertical slurry flows with coarse particles

2020 ◽  
Vol 68 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Artur Bartosik
Keyword(s):  
Mathematical Model ◽  
Reynolds Number ◽  
Friction Factor ◽  
Particle Diameter ◽  
Solid Particles ◽  
Coarse Particles ◽  
Carrier Liquid ◽  
Different Types ◽  
Slurry Flows ◽  
The Mathematical Model

AbstractThe paper presents validation of a mathematical model describing the friction factor by comparing the predicted and measured results in a broad range of solid concentrations and mean particle diameters. Three different types of solids, surrounded by water as a carrier liquid, namely Canasphere, PVC, and Sand were used with solids density from 1045 to 2650 kg/m3, and in the range of solid concentrations by volume from 0.10 to 0.45. All solid particles were narrowly sized with mean particle diameters between 1.5 and 3.4 mm. It is presented that the model predicts the friction factor fairly well. The paper demonstrates that solid particle diameter plays a crucial role for the friction factor in a vertical slurry flow with coarse solid particles. The mathematical model is discussed in reference to damping of turbulence in such flows. As the friction factor is below the friction for water it is concluded that it is possible that the effect of damping of turbulence is included in the KB function, which depends on the Reynolds number.

Motion of a Sphere on a Plane

1994 ◽  
Author(s):  
Yong-Xian Xu ◽  
Dilip Kohli ◽  
Larry Vezina ◽  
Daniel R. Speranza
Keyword(s):  
Mathematical Model ◽  
Initial Conditions ◽  
Contact Point ◽  
Break Point ◽  
Degree Of Freedom ◽  
Geometric Center ◽  
Inertia Properties ◽  
Gyroscopic Motion ◽  
The Mathematical Model ◽  
First Time

Abstract The motion of a sphere on a plane is a five degree-of-freedom motion. It consists of two independent translations of the geometric center of the sphere and three rotations corresponding to gyroscopic motion of the sphere. The trajectory of an imbalanced sphere on the plane depends on: (1) the physical and inertia properties of the sphere, (2) the initial conditions of motion, and (3) the friction between the sphere and the plane. To predict the trajectory of the sphere, a general Eulerian mathematical model is developed which takes into account these conditions. The mathematical model is verified through experimentation. For the first time, general characteristics of the translatory and rotatory motions of the imbalanced sphere with general inertia distribution are presented. The existence of the “break point” in the trajectory is illustrated by examples. The trajectory (track) of the contact point on the surface of the sphere is also analyzed.

The Estimation of the Thermal Properties of Refractory Materials According to the Temperatures Acceleration Curve at the Blast Furnace Blowing-In

2015 ◽  
Vol 1095 ◽  
pp. 476-482 ◽  
Author(s):  
A.N. Dmitriev ◽  
Maxim O. Zolotykh ◽  
Yury A. Chesnokov ◽  
Oleg Yu. Ivanov ◽  
Galina Yu. Vitkina
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Model ◽  
Blast Furnace ◽  
Thermal Properties ◽  
Thermal Conductivity Coefficient ◽  
Refractory Materials ◽  
Different Types ◽  
Definition Of ◽  
The Mathematical Model

In a laying of a hearth it is usually used to ten different types of the flameproof materials. The characteristics of materials declared by the manufacturer can differ from the actual. For creation of the mathematical model [1, 2] temperatures distributions in a laying of the concrete furnace it is necessary to know thermal conductivity of materials of the specific parties used at construction of the furnace. Definition of the thermal conductivity coefficient allows adapt mathematical model for specific conditions of use. The technique of determination of thermal properties of refractory materials on the temperatures acceleration curve at blowing-in of the blast furnace is described.

On Realization of Program Constraints: Part II—Practical Implications

1989 ◽  
Vol 56 (3) ◽  
pp. 680-684 ◽  
Author(s):  
Wojciech Blajer ◽  
Jan Parczewski
Keyword(s):  
Mathematical Model ◽  
Different Types ◽  
General Mathematical Model ◽  
Practical Implications ◽  
Program Constraint

Practical implications of a general mathematical model of realization of program constraints are investigated. Illustrative examples of different types of this realization are demonstrated and discussed. Some general conclusions concerning the problem of program constraint realization are drawn.

General Mathematical Model of Internal Meshing Spiral Bevel Gears for Nutation Drive

2011 ◽  
Vol 101-102 ◽  
pp. 708-712 ◽  
Author(s):  
Zheng Lin ◽  
Li Gang Yao
Keyword(s):  
Mathematical Model ◽  
3D Modeling ◽  
Gear Tooth ◽  
Spiral Bevel Gears ◽  
Bevel Gears ◽  
General Mathematical Model ◽  
Spiral Bevel ◽  
The Mathematical Model ◽  
Crown Gear ◽  
Internal Meshing

The general mathematical model of internal meshing spiral bevel gears for nutation drive is studied. Based on conventional enveloping theory and transmission principle, the meshing of two spiral bevel gears in nutation drive was substituted by the meshing of an imaginary rotating crown gear engaging with the external and internal bevel gear respectively. The general mathematical model of crown gear was established. Then the general mathematical model of internal meshing spiral bevel gears is obtained by matrix transformation, which is suitable for a variety of gear tooth profiles. Finally, the mathematical model and 3D modeling of double circular-arc spiral bevel gears are developed.

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