scholarly journals ANALYTICAL METHODS FOR CALCULATING FAN AERODYNAMICS

2015 ◽  
Vol 55 (6) ◽  
pp. 373
Author(s):  
Jan Dostal ◽  
Jan Kuzel
Keyword(s):  
Mathematical Model ◽  
Analytical Methods ◽  
Preliminary Design ◽  
Computer Programme ◽  
Aerospace Research ◽  
Model Based ◽  
The Creation ◽  
The Mathematical Model ◽  
Measuring Unit

This paper presents results obtained between 2010 and 2014 in the field of fan aerodynamics at the Department of Composite Technology at the VZLÚ aerospace research and experimental institute in Prague – Letnany. The need for rapid and accurate methods for the preliminary design of blade machinery led to the creation of a mathematical model based on the basic laws of turbomachine aerodynamics. The mathematical model, the derivation of which is briefly described below, has been encoded in a computer programme, which enables the theoretical characteristics of a fan of the designed geometry to be determined rapidly. The validity of the mathematical model is assessed continuously by measuring model fans in the measuring unit, which was developed and manufactured specifically for this purpose. The paper also presents a comparison between measured characteristics and characteristics determined by the mathematical model as the basis for a discussion on possible causes of measured deviations and calculation deviations.

scholarly journals COMPUTER SIMULATION AND ANALYTICAL SOLUTION OF FOUR BAR MECHANISM

2020 ◽  
pp. 120-128
Author(s):  
Darina Hroncová
Keyword(s):  
Mathematical Model ◽  
Analytical Solution ◽  
Mathematical Models ◽  
Computer Model ◽  
Analytical Methods ◽  
Kinematic Analysis ◽  
Linkage Mechanism ◽  
The Creation ◽  
Four Bar Linkage ◽  
The Mathematical Model

Urgency of the research. The use of computers in technical practice leads to the extension of the possibility of solving mathematical models. This makes it possible to gradually automate complex calculations of equations of mathematical models. It is necessary to input the relevant inputs of the mathematical model, to build a simulation computer model and to monitor and evaluate the output results using a computer's output device. Target setting. The possibilities of modeling a four-bar linkage mechanism by classical analytical methods and methodsusing computer modeling are presented in this paper.The problem is to describe the creation of a computer model and to show the mathematical model and its solution in the classical ways. Actual scientific researches and issues analysis. The inspiration for the creation of the article was the study of the mechanisms in the work [1-3] and the study of other resources available in library and journal materials, as well as prepared study materials for students of Technical university Kosice. Uninvestigated parts of general matters defining. The question of building a real mechanism model. The possibilities to building a real model, based on the result of simulation. The research objective. The aim of this paper is to develop a functional model of the mechanism in ADAMS/View and Matlab and its complete kinematic analysis.The statement of basic materials.The task was to create a computer model in MSC Adams and Matlab and to perform a four-bar linkage mechanism kinematic analysis. At the same time the classical procedure of analytical methods of kinematic analysis was described. Kinematic сharacteristics of driven members and their selected points were determined. The movement of the parts of the mechanism in its significant points was analyzed. The results of the solution were shown in both programs in graphical form. Kinematic analysis was performed by both vector and graphical methods. Finally, the results with a graphical representation of parameters such as angular displacement, angular velocity and angular acceleration of mechanism members are presented in this work. The results of these solutions are created in the form of graphs. To ensure that the results do not differ from the model real, a good computer model gradually was created by its verification and modification, which is one of the advantages of MSC Adams. The practical applicability of the mathematical model was limited by the existence of an analytical solution. Conclusions. The development of computer technology has expanded the limit of solvability of mathematical models and made it possible to gradually automate the calculation of equations of mathematical models. In a computer model the auto-mated calculation can be treated as a real object sample. In various variations of calculation, we can monitor and measure the behavior of an object under different conditions, under the influence of different inputs. Graphical and vector methods were used for classical analytical methods. MSC Adams and Matlab were used for the automated calculations.

Accommodating Thickness in Origami-Based Deployable Arrays1

2013 ◽  
Vol 135 (11) ◽  
Author(s):  
Shannon A. Zirbel ◽  
Robert J. Lang ◽  
Mark W. Thomson ◽  
Deborah A. Sigel ◽  
Phillip E. Walkemeyer ◽  
...  
Keyword(s):  
Mathematical Model ◽  
High Ratio ◽  
Physical Models ◽  
Solar Array ◽  
Outer Diameter ◽  
Space Applications ◽  
The Creation ◽  
The Mathematical Model

The purpose of this work is to develop approaches to accommodate thickness in origami-based deployable arrays with a high ratio of deployed-to-stowed diameter. The origami flasher model serves as a basis for demonstrating the approach. A thickness-accommodating mathematical model is developed to describe the flasher. Practical modifications are presented for the creation of physical models and two options are proposed: allowing the panels to fold along their diagonals or applying a membrane backing with specified widths at fold-lines. The mathematical model and hardware modifications are employed to create several physical models. The results are general and apply to a range of applications. An example is provided by the application that motivated the work: a deployable solar array for space applications. The model is demonstrated in hardware as a 1/20th scale prototype with a ratio of deployed-to-stowed diameter of 9.2 (or 1.25 m deployed outer diameter to 0.136 m stowed outer diameter).

scholarly journals DIESEL SUPPLY PLANNING FOR OFFSHORE PLATFORMS BY A MATHEMATICAL MODEL BASED ON THE VEHICLE ROUTING PROBLEM WITH REPLENISHMENT

2016 ◽  
Author(s):  
Rodrigo De Alvarenga Rosa ◽  
Henrique Fiorot Astoures ◽  
André Silva Rosa
Keyword(s):  
Mathematical Model ◽  
Vehicle Routing ◽  
Vehicle Routing Problem ◽  
Oil And Gas ◽  
Offshore Platforms ◽  
Oil Exploration ◽  
Routing Problem ◽  
Model Based ◽  
Supply Planning ◽  
The Mathematical Model

Oil exploration in Brazil is mainly held by offshore platforms which require the supply of several products, including diesel to maintain its engines. One strategy to supply diesel to the platforms is to keep a vessel filled with diesel nearby the exploration basin. An empty boat leaves the port and goes directly to this vessel, then it is loaded with diesel. After that, it makes a trip to supply the platforms and when the boat is empty, it returns to the vessel to be reloaded with more diesel going to another trip. Based on this description, this paper proposes a mathematical model based on the Vehicle Routing Problem with Intermediate Replenishment Facilities (VRPIRF) to solve the problem. The purpose of the model is to plan the routes for the boats to meet the diesel requests of the platform. Given the fact that in the literature, papers about the VRPIRF are scarce and papers about the VRPIRF applied to offshore platforms were not found in the published papers, this paper is important to contribute with the evolution of this class of problem, bringing also a solution for a real application that is very important for the oil and gas business. The mathematical model was tested using the CPLEX 12.6. In order to assess the mathematical model, tests were done with data from the major Brazilian oil and gas company and several strategies were tested.DOI: http://dx.doi.org/10.4995/CIT2016.2016.2217

Modeling the Maneuvering Behavior of Container Carriers in Shallow Water

2007 ◽  
Vol 51 (04) ◽  
pp. 287-296 ◽  
Author(s):  
G. Delefortrie ◽  
M. Vantorre
Keyword(s):  
Mathematical Model ◽  
Shallow Water ◽  
Independent Set ◽  
Model Tests ◽  
Forward Speed ◽  
Ship Maneuvering ◽  
Model Based ◽  
Captive Model Tests ◽  
Water Effects ◽  
The Mathematical Model

Due to the expansion of the dimensions of container vessels, the available maneuvering space in harbor areas and their access channels is decreasing as waterway authorities are often unable to increase the channel dimensions at the same pace. The under keel clearance is an especially important parameter for ship maneuver-ability and controllability. After an overview of the shallow water effects on ship maneuvering, a new mathematical maneuvering model based on captive model tests is introduced. The mathematical model is valid in a large under keel clearance range and is applicable in four quadrants of forward speed: propeller rate combinations, drift angles, and yaw angles. The mathematical model has been validated by means of an independent set of captive model tests.

Analysis of the Mathematical Model of the Spray Dose Applied by the Field Sprayer Nozzles

2016 ◽  
Vol 20 (2) ◽  
pp. 71-79
Author(s):  
Karol Garbiak ◽  
Jan Jurga
Keyword(s):  
Mathematical Model ◽  
Angular Velocity ◽  
Forward Speed ◽  
Spray Application ◽  
Suggested Model ◽  
Independent Variables ◽  
Model Based ◽  
The Mathematical Model

AbstractThe article presents analysis of the mathematical model for determination of a momentary dose of spray applied by the field sprayer nozzles which move on the curve with the forward speed the value of which may differ from the speed accepted for regulation. Regulation speed and regulation dose, real forward speed of a sprayer, angular velocity during the curve movement, and the coefficient of the nozzle location towards the axis of the sprayer turn are independent variables in the suggested model. Based on the mathematical model, plots were drawn and analyses of relation of the spray dose to particular variables were carried out including inter alia, a repeated field spray, application of a dose which considerably differs from the regulation dose and diversity of the dose on the working width of the sprayer.

The Converter Steelmaking End Point Prediction Model Based on RBF Neural Network

2014 ◽  
Vol 577 ◽  
pp. 98-101
Author(s):  
Xian Liang Dong ◽  
Shi Dong
Keyword(s):  
Neural Network ◽  
Mathematical Model ◽  
Prediction Model ◽  
Carbon Content ◽  
Rbf Neural Network ◽  
Converter Steelmaking ◽  
Prediction Problem ◽  
Model Based ◽  
End Point ◽  
The Mathematical Model

The mathematical model of convert steelmaking end point prediction model based on RBF(Radical Basis Function) is presented in this paper. According to the end point prediction problem of the converter steelmaking production prediction problem, we establish the forecast model of converter steelmaking process which describes the relationship between variables such as hot metal quality, oxygen blowing, the quality of the cooling agent and additives etc. and the end point molten steel temperature and carbon content. The prediction system is multidimensional and nonlinear. The model between variables and the target is unknown. For this situation, this paper applies RBF neural network to forecast target, establishing the prediction model based on RBF neural network. So as to obtain the variables and the mathematical model between steel endpoint temperature and carbon content.

scholarly journals Simulation of the Distribution of Nanoplates in a Liquid

2021 ◽  
Vol 27 (4) ◽  
pp. 647-655
Author(s):  
A. M. R. Al-Mashhadani ◽  
V. F. Pershin
Keyword(s):  
Mathematical Model ◽  
Physical Model ◽  
Critical Concentration ◽  
Solid Particles ◽  
The Real ◽  
Model Based ◽  
Real Process ◽  
Layered Crystals ◽  
The Mathematical Model

The general regularities of exfoliation of layered crystals are considered. A physical model based on the analogy of the spatial packing of polydisperse spherical solid particles is proposed to simulate the distribution of nanoplates in a liquid. Mathematical dependences have been obtained for calculating the critical concentration of aggregation of nanoplates, using graphene as an example. The verification of the adequacy of the mathematical model to the real process was carried out.

Visual Simulation of Shells Exploding in Virtual Environment

2013 ◽  
Vol 756-759 ◽  
pp. 1809-1813
Author(s):  
Gong Lin ◽  
Da Wei Jiang
Keyword(s):  
Mathematical Model ◽  
Real Time ◽  
Dynamic Model ◽  
Virtual Environment ◽  
Particle System ◽  
Texture Mapping ◽  
Visual Simulation ◽  
Model Based ◽  
Mapping Techniques ◽  
The Mathematical Model

The mathematical model of smoke diffusion and dissipation when shells exploding is studied, and the dynamic model based on particle system controlled by the mathematical model and texture mapping techniques is established. The visual simulation of the method is efficient and real-time.

scholarly journals Tactical Analysis Through Objective Data in Football

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Akira Yamanaka ◽  
Hiroshi Otsuka ◽  
Tatsuya Deguchi ◽  
Ken Okihara ◽  
Dota Otsuka ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Team Sports ◽  
Numerical Data ◽  
Objective Data ◽  
Match Analysis ◽  
Model Based ◽  
Video Images ◽  
Different Types ◽  
The Mathematical Model ◽  
Insight Into

<p>Tactical analysis in football has rarely been conducted using a mathematical model with numerical data (although tactical analysis through objective data has been used more often). Therefore, this study establishes principles for tactical analysis in team sports using numerical data, through a mathematical model based on the location of the players and the ball. A competitive match between Sanfrecce Hiroshima (home) and Ehime FC (away) in the third round of the Japanese Emperor’s Cup 2011 was filmed and used for the match analysis. Observations were made by a team analyst as well as extracted from official match records. The main procedure in the research flow was to establish a mathematical offence/defence model based on tactical concepts in football, which was applied for the location of players, which, in turn, was quantified from video images in order to categorise a team’s tactical performance (in relation to attacking or defending). Furthermore, the authors focused on attacking categories and identified different types of passes during a specific period, as well as comparing these findings with an actual match video. The results obtained from the numerical data derived from applying the offence/defence model led to the same overview as the tactical analysis produced by a team analyst. In addition, the results when categorising types of passes (as extracted through the mathematical model) again mirrored those retrieved from an actual match video. This leads to the conclusion that the offence/defence model could provide relevant insight into types of attacks. The data revealed that football tactical analysis can be successfully performed using a numerical model, which might possibly enable automatic tactical analysis of football games without a match analyst.</p>

scholarly journals Operations Research Model Formulation for Road Maintenance Case

2019 ◽  
Vol 22 ◽  
pp. 32-36
Author(s):  
Jānis Pekša ◽  
Kristaps-Pēteris Rubulis
Keyword(s):  
Mathematical Model ◽  
Literature Review ◽  
Operations Research ◽  
Analytical Methods ◽  
Road Maintenance ◽  
Research Model ◽  
Model Formulation ◽  
Basic Principles ◽  
The Mathematical Model

Operations research can be used to apply analytical methods that help make precise and reasonable decisions. In road maintenance, basic principles of operations research are used to create model formulation that could help lower costs in case of an inaccurately made decision. First, the paper provides a literature review on different model formulations. Afterward, hypotheses are proposed regarding the model formulation, and then the model that minimises total generalised costs from wrong duty orders for road maintenance is offered. In conclusion, the paper evaluates the hypotheses and the process of improving the mathematical model.

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