scholarly journals Improvement of the design method of thermal networks: serial connection of heat exchangers

2021 ◽  
Vol 4 (4) ◽  
pp. 329-337
Author(s):  
Georgy V. Derevyanko ◽  
Vladimir I. Mescheryakov
Keyword(s):  
Mathematical Model ◽  
Heat Exchange ◽  
Energy Exchange ◽  
Design Method ◽  
System Of Equations ◽  
Serial Connection ◽  
The Matrix ◽  
Minimum Uncertainty ◽  
The Mathematical Model ◽  
Energy Conservation Law

The mathematical model of the system is considered consisting of a series connection of three heating devices. A system of equations based on the energy conservation law is constructed, which turns out to be incomplete. It is shown that, given the known requirements for the system, expressed only in the efficiency of the system, the formalization of design often becomes insoluble. The system of equations is supplemented with expressions in accordance with the hypothesis of the proportionality of the amount of energy in an element and is presented in matrix form. The design task is reduced to determining the elements of the matrix by the value of the determinants. Analysis of the mathematical model made it possible to obtain an expression for the efficiency of the system as a function of energy exchange in its elements. This made it possible to obtain solutions for flows and their relationships in the elements of the system. In addition, the efficiency of inter-network and intra-network energy exchange has been determined, which satisfy the principles of equilibrium and minimum uncertainty in the values of the average parameters of the system. As an application, one of the main parameters, NTU, is considered, which determines the area of heat exchange with the external environment and the mass and dimensional characteristics of the heat exchange system. Models of direct and opposite switching on of flows with variations of flows and the value of the surface of devices when meeting the requirements for the efficiency of the system are considered. The results of comparing the design process with the iterative calculation method are presented and the advantages of the proposed approach are shown

Optimization Research on Dynamic Balance of Spatial Engine under Limiting Shaking Moment

2009 ◽  
Vol 626-627 ◽  
pp. 693-698
Author(s):  
Yong Yong Zhu ◽  
S.Y. Gao
Keyword(s):  
Mathematical Model ◽  
Objective Function ◽  
Kinetic Analysis ◽  
Optimization Design ◽  
Design Method ◽  
Dynamic Balance ◽  
Optimized Design ◽  
Design Variables ◽  
The Mathematical Model ◽  
Shaking Moment

Dynamic balance of the spatial engine is researched. By considering the special wobble-plate engine as the model of spatial RRSSC linkages, design variables on the engine structure are confirmed based on the configuration characters and kinetic analysis of wobble-plate engine. In order to control the vibration of the engine frame and to decrease noise caused by the spatial engine, objective function is choosed as the dimensionless combinations of the various shaking forces and moments, the restriction condition of which presents limiting the percent of shaking moment. Then the optimization design is investigated by the mathematical model for dynamic balance. By use of the optimization design method to a type of wobble-plate engine, the optimization process as an example is demonstrated, it shows that the optimized design method benefits to control vibration and noise on the engines and improve the performance practically and theoretically.

Research on the Conformal Phased-Array Antenna

2014 ◽  
Vol 685 ◽  
pp. 324-327
Author(s):  
Shuang Zhao ◽  
Yu Bo Yue
Keyword(s):  
Mathematical Model ◽  
Antenna Array ◽  
Phased Array ◽  
Design Method ◽  
Array Antenna ◽  
Phased Array Antenna ◽  
Conformal Antenna ◽  
Conformal Array ◽  
Design Requirements ◽  
The Mathematical Model

The mathematical model of conformal antenna array is the premise and basis of the conformal array antenna signal processing. Based on the analysis of the antenna array, a design method for adjusting the direction of the conformal array antenna is proposed. Through simulation, the pattern of antenna meets the actual needs of the project and it reaches pre design requirements.

scholarly journals Innovative technology for reducing the rate of sediment formation in the power plants channels

2020 ◽  
Vol 164 ◽  
pp. 01033
Author(s):  
Anatoly Muraviev ◽  
Alexander Nadeev ◽  
Alexander Naumov ◽  
Inna Pereslavtseva
Keyword(s):  
Mathematical Model ◽  
Mass Transfer ◽  
Heat Exchange ◽  
Power Plants ◽  
Particle Distribution ◽  
Innovative Technology ◽  
System Of Equations ◽  
Sediment Formation ◽  
Shell And Tube

This paper considers the increasing the mass transfer intensity due to the use of annular baffles in the tubes of shell-and-tube heat exchange apparatuses. A mathematical model for calculating the system of equations for the evolution of particle distribution in the form of sediments has been developed.

Research on the Blank Design Method of Closed Rolling the High-Neck Flange

2011 ◽  
Vol 314-316 ◽  
pp. 594-598
Author(s):  
Min Xiao ◽  
Xue Dao Shu
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Design Method ◽  
Scientific Basis ◽  
Shape Design ◽  
Blank Design ◽  
Rolling Method ◽  
Blank Shape ◽  
Blank Size ◽  
The Mathematical Model

Blank shape design is the prerequisite and foundation of optimization for the closed forming the high-neck flange. This paper obtained the design formulas of blank size with analyzing the mathematical model of flank blank based on the principle of volume invariably during the rolling process.The blank of a special flange was designed by this method which was validated by the numerical simulation under the DEFORM software. The results indicate that the product is qualified with the blank shape based on this method. These research conclusions can provide scientific basis for forming the high-neck flange with rolling method.

Design Method of Self-Loading Device of the Side-Crane Used for Container

2012 ◽  
Vol 466-467 ◽  
pp. 951-955
Author(s):  
Jun Qing Zhan ◽  
Xiao Mei Feng ◽  
Li Shun Li ◽  
Xiang De Meng
Keyword(s):  
Mathematical Model ◽  
Structural Design ◽  
Design Method ◽  
The Self ◽  
Design Calculation ◽  
Force Analysis ◽  
Loading Device ◽  
Calculation Results ◽  
The Mathematical Model ◽  
Flat Ground

The self-loading device used for side-crane is put forward. Its structure is presented. Based on the force analysis when the side-crane works at flat ground, the mathematical model is established when the crane working at uneven ground. And the design calculation is performed. The self-loading device’s optimal design is accomplished. Based on the above calculation results, the self-loading prototype is manufactured. And the design method can be adopted to the similar equipment’s structural design.

scholarly journals Research on the Cutting Principle and Tool Design of Gear Skiving Based on the Theory of Conjugate Surface

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Peng Wang ◽  
Jingcai Li ◽  
Lin Han
Keyword(s):  
Mathematical Model ◽  
Design Principle ◽  
Design Method ◽  
Tool Design ◽  
Theoretical Research ◽  
Machining Accuracy ◽  
Rake Face ◽  
Key Factors ◽  
Flank Face ◽  
The Mathematical Model

Tool design is one of the key factors that restrict the development of gear skiving technology since the design principle does not correspond to the cutting principle. The existing skiving tool cannot achieve ideal machining accuracy and reasonable cutting angles. In view of this, some research has been done in this paper. Firstly, the skiving principle is investigated essentially according to the skiving motions. Then, the principle of tool design is analyzed based on the theory of conjugate surface, and a new tool design method is proposed to match the skiving principle. For this, all the skiving patterns for various kinds of workpieces are enumerated and summarized to abstract a normalized skiving model. Based on this, the mathematical model of the conjugate surface is then derived to lay the foundation for tool design. Then, the design methods of cutting edge, rake face, and flank face are proposed. An example is presented at last, and the cutting simulation is conducted. The result proves that the proposed methods are correct and valid. The theoretical research in this paper could promote the improvement of skiving tools.

scholarly journals MATHEMATICAL AND PHYSICAL BASIS FOR DEVELOPING A SIMULATOR FOR TOWING AND PULLING OF WHEELED AND TRACKED MACHINES

2021 ◽  
Vol 5 (4) ◽  
pp. 135-139
Author(s):  
Alexander Serhieiev ◽  
Andriy Krivoshapka ◽  
Oleksandr Isakov ◽  
Vyacheslav Lysenko ◽  
Viktor Moskalenko ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Physical Basis ◽  
Design Parameters ◽  
System Of Equations ◽  
Aramid Fibers ◽  
Tracked Vehicles ◽  
General Scientific ◽  
And Performance ◽  
The Mathematical Model ◽  
Physical Quantities

The subject matter of the article is the towing and pulling of wheeled and tracked vehicles with the use of cable ropes and dynamic slings. The goal of the study is to determine the mathematical and physical basis for the development of a simulator for towing and pulling wheeled and tracked vehicles for researching to study the possibility of using aramid fibers of cable-ropes and dynamic slings. The tasks to be solved are: based on the analysis of the main roads and ground characteristics to formalize the list of calculated parameters and physical quantities determine the amount of evacuation work when pulling, towing and transporting wheeled and tracked vehicles; to develop a mathematical model that describes the process of pulling and towing wheeled and tracked vehicles using cable ropes and dynamic slings. General scientific and special methods of scientific knowledge are used. The following results are obtained. By analyzing the main characteristics of roads and ground, a formalized list of design parameters and physical quantities that determine the volume of evacuation work during the towing and pulling of wheeled and tracked vehicles was obtained. Mathematical model, describes the process of pulling and towing wheeled and tracked machines using cable ropes and dynamic slings have been  compiled as a system of equations with different order. analyzed existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles. Existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles have been analyzed. Conclusions. The main roads and ground characteristics  that determine the vehicles. evacuation conditions are the following: the type of road or ground, their possibility depending on the season and precipitation, the presence of ascents and descents, as well as the nature of road (ground) interaction with caterpillars determined by resistance coefficients. movement and traction. The mathematical model of pulling a wheeled and tracked vehicle using cable ropes and dynamic can be presented as a system of equations: the jerk carried out by the machine in time reflected third-order differential equation, assuming that all the energy accumulated by the cable is numerically equal to the work of moving stuck machine, corresponds to the equality of the corresponding integrals; the properties of aramid fibers that affect the strength and performance characteristics of cable ropes can be formally expressed through the elongation of the cable. Analysis of strength and service properties of aramid fibers opens the way to improvement of manufacturing technology of cable ropes and dynamic slings for pulling and towing of wheeled and tracked vehicles.

Inverse Dynamic Analysis of Spatial Manipulators with Elastic Legs

1988 ◽  
Vol 12 (2) ◽  
pp. 63-69
Author(s):  
K.H. Low ◽  
R.N. Dubey
Keyword(s):  
Mathematical Model ◽  
Hybrid System ◽  
Perturbation Technique ◽  
Flexible Manipulator ◽  
System Of Equations ◽  
Joint Motion ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis ◽  
Deflection Theory ◽  
The Mathematical Model

This work presents a general formulation of flexible manipulator systems. The associated mathematical model results in a hybrid system of equations involving both ordinary and partial differential equations. The perturbation technique and model analysis have been used for the solution. In addition to the lineal deflection theory, an unperturbed joint-motion assumption has then been employed in order to further simplify the mathematical model. Finally, an inverse dynamic problem is solved using the proposed methodology.

scholarly journals Investigation of Thermodynamic Properties of the Slurry of the Molding Process Beryllium Ceramics

Proceedings ◽  
2018 ◽  
Vol 2 (22) ◽  
pp. 1391
Author(s):  
Zamira Sattinova ◽  
Gaukhar Ramazanova ◽  
Bakhytzan Assilbekov ◽  
Elmira Mussenova
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Model ◽  
Thermal Properties ◽  
Heat Exchange ◽  
Thermodynamic Properties ◽  
Physical Properties ◽  
Beryllium Oxide ◽  
Molding Process ◽  
The Mathematical Model

Obtaining of ceramic fabrications by hot molding from dispersion materials with anomalous physical properties, such as BeO is particularly complicated. In this case, the difficulties of obtaining of quality products were caused firstly by thermal properties of beryllium oxide, in particular, its unique thermal conductivity. Results of experiments and calculations of the mathematical model of the motion and heat exchange of the slurry mass in the annular cavity are presented. The results of experiments and calculations show the process of molding of the slurry in the annular cavity.

Research on Tooth Profile Design of Spur Gears Based on Line of Action

2013 ◽  
Vol 631-632 ◽  
pp. 817-823
Author(s):  
Jian Wang ◽  
Liang Hou ◽  
Shan Ming Luo
Keyword(s):  
Mathematical Model ◽  
Design Method ◽  
Tooth Profile ◽  
Spur Gears ◽  
On Line ◽  
Profile Design ◽  
The Mathematical Model

This paper aims to propose a design method for tooth profiles of spur gears based on given line of action. A simplified derivation of the mathematical model of tooth profiles is introduced according to the meshing theory. Tooth profiles of spur gears, using a parabola as line of action, is established. The result shows that it will be better to control the performances of a gear set by specifying the shape of the line of action rather than specifying tooth profiles of mating gear.

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