Simplified Calculation of the Eccentric Press Stiffness

2014 ◽  
Vol 613 ◽  
pp. 402-407
Author(s):  
Peter Demeč ◽  
Dominika Palaščáková
Keyword(s):  
Transfer Matrix ◽  
Cross Sections ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Mechanical Systems ◽  
Matrix Form ◽  
Entire Length ◽  
The Press ◽  
The Cross ◽  
Simplified Calculation

The article deals with the simplified calculation of the stiffness of the eccentric press frame. The described method applies to the solving of problem a mathematical identification of condition parameters in the press frame the transfer matrix method (TMM), which is in essence a matrix form of initial parameters method. This method is suitable for mechanical systems with continuously distributed mass in space while the cross-sections along the entire length of the system are not constant.

Extension of the Transfer Matrix Method for Rotordynamic Analysis to Include a Direct Representation of Conical Sections and Trunnions

1980 ◽  
Vol 102 (1) ◽  
pp. 122-129 ◽  
Author(s):  
M. S. Darlow ◽  
B. T. Murphy ◽  
J. A. Elder ◽  
G. N. Sandor
Keyword(s):  
Transfer Matrix ◽  
Cross Sections ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Critical Speed ◽  
Axial Direction ◽  
Matrix Analysis ◽  
Beam Elements ◽  
Conical Section ◽  
Rotor Model

The transfer matrix method for rotordynamic analysis (alternately known as the HMP or LMP method) has enjoyed wide popularity due to its flexibility and ease of application. A number of computer programs are generally available which use this method in various forms to perform undamped critical speed, unbalance response, damped critical speed and stability analyses. For all of these analyses, the assembly of the transfer matrices from the rotor model is essentially the same. In all cases, the rotor model must be composed entirely of cylindrical beam elements. There are two situations when this limitation is not desirable. The first situation is when the rotor being modelled has one or more sections whose cross sections vary continually in the axial direction. The most common of these sections is the conical section. Presently, a conical section must be modelled as a series of “steps” of cylindrical sections. This adversely affects both the simplicity and accuracy of the rotor model. The second situation when current transfer matrix techniques are not accurate is when the rotor being modelled has one or more sections that do not behave as beam elements. The most common example is a trunnion which behaves as a plate. This paper describes the analytical basis and the method of application for direct representation of conical sections and trunnions for a transfer matrix analysis. Analytical results are currently being generated to demonstrate the need for and advantages of these modelling procedures.

Discrete Time Transfer Matrix Method for Launch Dynamics Modeling and Cosimulation of Self-Propelled Artillery System

2012 ◽  
Vol 80 (1) ◽  
Author(s):  
Bao Rong ◽  
Xiaoting Rui ◽  
Ling Tao
Keyword(s):  
Transfer Matrix ◽  
Discrete Time ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Mechanical Systems ◽  
Coupled Systems ◽  
Order System ◽  
Time Transfer ◽  
Integration Algorithm ◽  
Complex Mechanical Systems

In many industrial applications, complex mechanical systems can often be described by multibody systems (MBS) that interact with electrical, flowing, elastic structures, and other subsystems. Efficient, precise dynamic analysis for such coupled mechanical systems has become a research focus in the field of MBS dynamics. In this paper, a coupled self-propelled artillery system (SPAS) is examined as an example, and the discrete time transfer matrix method of MBS and multirate time integration algorithm are used to study the dynamics and cosimulation of coupled mechanical systems. The global error and computational stability of the proposed method are discussed. Finally, the dynamic simulation of a SPAS is given to validate the method. This method does not need the global dynamic equations and has a low-order system matrix, and, therefore, exhibits high computational efficiency. The proposed method has advantages for dynamic design of complex mechanical systems and can be extended to other coupled systems in a straightforward manner.

Free vibration analysis of axial-loaded beams with variable cross sections and multiple concentrated elements

2021 ◽  
pp. 107754632110128
Author(s):  
Yunxing Du ◽  
Peng Cheng ◽  
Fen Zhou
Keyword(s):  
Free Vibration ◽  
Transfer Matrix ◽  
Cross Sections ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Free Vibration Analysis ◽  
Frequency Equation ◽  
Variable Cross ◽  
Bending Vibrations ◽  
Euler Bernoulli Beam

A transfer matrix method is used to study free vibration characteristics of an axial-loaded Euler–Bernoulli beam with variable cross sections and multiple concentrated elements in the article. The differential equation for bending vibrations of the beam element is solved by the Frobenius method, and the solution is in power series form. Then, the transfer matrix method is applied to establish the state vector equation for both ends of the beam. Combined with boundary conditions, the frequency equation is obtained and expressed in a two-order determinant. The numerical results in this article are compared with those of the finite element method, which illustrates the accuracy of the method we proposed. The influence of the size of each concentrated elements and axial force on the natural frequency coefficients and the influence of the concentrated elements on the first critical buckling load are discussed.

Response Calculation and Analysis of Torsional Vibration of Turbine-Generator Shafts

2006 ◽  
Author(s):  
Zhi Zhang ◽  
Dongmei Du ◽  
Qing He
Keyword(s):  
Power System ◽  
Electric Power ◽  
Transfer Matrix ◽  
Cross Sections ◽  
Torsional Vibration ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Electric Power System ◽  
Turbine Generator ◽  
Lumped Model

Due to the disturbance of electric power system or other shock load, the torsional vibration of turbine-generator shafts occurs. It is significant to calculate the response of torsional vibration excited by the disturbance of electric power system in order to analyze and prevent catastrophic accident. The multi-mass lumped model of turbine-generator shafts is used. A new method of response calculation of torsional vibration of turbine-generator shafts, the Increment Transfer Matrix method (ITM), which combines the Riccati transfer matrix method with the Newmark-β step-by-step integral method, is presented. By the ITM method, the transient response of torsional vibration of turbine-generator shafts, especially at the dangerous cross-sections, can be calculated. The responses of torsional vibration of 200MW turbine-generator shafts due to the generator at non-all-phase operation are calculated and analyzed. The cause of bolt broken of the coupling of intermediate-pressure rotor and low-pressure rotor and the coupling of generator and exciter are discussed. The results are identical with the data recorded in field.

scholarly journals Torsional vibration of suspension bridge with a variable cross section

1981 ◽  
Vol 3 (2) ◽  
pp. 22-26
Author(s):  
Nguyen Van Tinh
Keyword(s):  
Computer Program ◽  
Transfer Matrix ◽  
Cross Section ◽  
Cross Sections ◽  
Torsional Vibration ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Suspension Bridge ◽  
Variable Cross Section ◽  
Variable Cross

The transfer matrix method to torsion’ al vibrations of a suspension bridge with variable cross sections is reported. The method described above is particularly suitable for implementing an efficient computer program. A numerical example is also givens.

Sign in / Sign up

Export Citation Format

Share Document