Modeling of Dynamic Interaction Between Gun System Components During the Recoil Motion of the Gun

2009 ◽  
Author(s):  
Nadeem Ahmed ◽  
R. D. Brown ◽  
J. G. Hetherington
Keyword(s):  
Dynamic Response ◽  
Computer Modelling ◽  
Dynamic Interaction ◽  
Design Parameters ◽  
Physical Interaction ◽  
Firing Cycle ◽  
Factors Affecting ◽  
Contact Algorithm ◽  
Number Of Factors ◽  
System Components

The accuracy and consistency of a large caliber gun is largely dependent on its dynamic response during the firing cycle. A number of factors affecting the dynamic response of the gun include, the offset masses attached to the barrel, offset forces acting at a distance from the barrel axis and the dynamic interaction between the gun system components, including the shot-barrel interaction. Computer based modelling techniques can be used to model and simulate the motion of the gun during the firing cycle. These techniques are helpful in predicting the dynamic response of the gun system as well as the accuracy and consistency of the gun. A finite element computer modelling program ‘ANSYS’ was used to model a 120mm direct fire tank gun and simulate the dynamic response during the recoil motion. The contact algorithm in ‘ANSYS’ was used to simulate physical interaction between the gun system components. Simulations were also carried out in the Gun Dynamics program ‘SIMBAD’ by using the same gun system profile and the results obtained from both programs were compared. A case study is also presented to investigate the effect of gun design parameters on the dynamic response of the gun.

A Simplified Design Model for Modular Steel Buildings Subject to Vapor Cloud Explosions (VCEs)

2020 ◽  
Vol 14 ◽  
Author(s):  
Osama Bedair
Keyword(s):  
Dynamic Response ◽  
Minimum Cost ◽  
Design Parameters ◽  
Front Wall ◽  
Steel Buildings ◽  
Element Analysis ◽  
Analysis And Design ◽  
Vapor Cloud ◽  
Building Components ◽  
Analytical Expressions

Background: Modular steel buildings (MSB) are extensively used in petrochemical plants and refineries. Limited guidelines are available in the industry for analysis and design of (MSB) subject to accidental vapor cloud explosions (VCEs). Objectives: The paper presents simplified engineering model for modular steel buildings (MSB) subject to accidental vapor cloud explosions (VCEs) that are extensively used in petrochemical plants and refineries. Method: A Single degree of freedom (SDOF) dynamic model is utilized to simulate the dynamic response of primary building components. Analytical expressions are then provided to compute the dynamic load factors (DLF) for critical building elements. Recommended foundation systems are also proposed to install the modular building with minimum cost. Results: Numerical results are presented to illustrate the dynamic response of (MSB) subject to blast loading. It is shown that (DLF)=1.6 is attained at (td/t)=0.4 for front wall (W1) with (td/T)=1.25. For side walls (DLF)=1.41 and is attained at (td/t)=0.6. Conclusions: The paper presented simplified tools for analysis and design of (MSB) subject accidental vapor cloud blast explosions (VCEs). The analytical expressions can be utilized by practitioners to compute the (MSB) response and identify the design parameters. They are simple to use compared to Finite Element Analysis.

Impact of climatic conditions on the parameters of failure flow of military vehicles

2021 ◽  
pp. 095440702110202
Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys
Keyword(s):  
Climatic Factors ◽  
Armed Forces ◽  
Climatic Conditions ◽  
Operating Conditions ◽  
Technical Equipment ◽  
Factors Affecting ◽  
Military Vehicles ◽  
Equipment Reliability ◽  
Number Of Factors ◽  
The Impact

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.

Green roof hydrologic performance and modeling: a review

2013 ◽  
Vol 69 (4) ◽  
pp. 727-738 ◽  
Author(s):  
Yanling Li ◽  
Roger W. Babcock
Keyword(s):  
Peak Flow ◽  
Green Roof ◽  
Field Measurements ◽  
Green Roofs ◽  
Economic Benefits ◽  
Design Parameters ◽  
Technical Literature ◽  
Factors Affecting ◽  
Model Soil ◽  
Runoff Volume

Green roofs reduce runoff from impervious surfaces in urban development. This paper reviews the technical literature on green roof hydrology. Laboratory experiments and field measurements have shown that green roofs can reduce stormwater runoff volume by 30 to 86%, reduce peak flow rate by 22 to 93% and delay the peak flow by 0 to 30 min and thereby decrease pollution, flooding and erosion during precipitation events. However, the effectiveness can vary substantially due to design characteristics making performance predictions difficult. Evaluation of the most recently published study findings indicates that the major factors affecting green roof hydrology are precipitation volume, precipitation dynamics, antecedent conditions, growth medium, plant species, and roof slope. This paper also evaluates the computer models commonly used to simulate hydrologic processes for green roofs, including stormwater management model, soil water atmosphere and plant, SWMS-2D, HYDRUS, and other models that are shown to be effective for predicting precipitation response and economic benefits. The review findings indicate that green roofs are effective for reduction of runoff volume and peak flow, and delay of peak flow, however, no tool or model is available to predict expected performance for any given anticipated system based on design parameters that directly affect green roof hydrology.

Model of a Slip Sensor

1993 ◽  
Vol 207 (1) ◽  
pp. 55-64 ◽  
Author(s):  
F Eghtedari ◽  
S H Hopkins ◽  
D T Pham
Keyword(s):  
Solid State ◽  
Computer Modelling ◽  
Design Parameters ◽  
Slip Sensor ◽  
Fringe Patterns ◽  
Switching Characteristics ◽  
Main Components ◽  
Photoelastic Sensor ◽  
Slip Detection

This paper describes the mathematical and computer modelling of a photoelastic sensor for slip detection. The main components of the sensor are a photoelastic transducer and a solid state camera. When under stress, the photoelastic transducer generates optical fringe patterns which are captured digitally by the camera. The model developed encompasses the mechanical and optical behaviours of the photoelastic transducer and the switching characteristics of the camera pixels. The model has been employed to study the effects of different design parameters on the sensor's slip resolution.

A Parametric Examination of the Factors Affecting the Performance of a Diffusion Absorption Refrigeration System

2021 ◽  
pp. 1-38
Author(s):  
Noman Yousuf ◽  
Timothy Anderson ◽  
Roy Nates
Keyword(s):  
Waste Heat ◽  
Operating Conditions ◽  
Design Parameters ◽  
Working Fluid ◽  
Low Grade ◽  
Absorption Refrigeration ◽  
Factors Affecting ◽  
Thermally Driven ◽  
Mass Flowrate ◽  
Diffusion Absorption

Abstract Despite being identified nearly a century ago, the diffusion absorption refrigeration (DAR) cycle has received relatively little attention. One of the strongest attractions of the DAR cycle lies in the fact that it is thermally driven and does not require high value work. This makes it a prime candidate for harnessing low grade heat from solar collectors, or the waste heat from stationary generators, to produce cooling. However, to realize the benefits of the DAR cycle, there is a need to develop an improved understanding of how design parameters influence its performance. In this vein, this work developed a new parametric model that can be used to examine the performance of the DAR cycle for a range of operating conditions. The results showed that the cycle's performance was particularly sensitive to several factors: the rate of heat added and the temperature of the generator, the effectiveness of the gas and solution heat exchangers, the mass flowrate of the refrigerant and the type of the working fluid. It was shown that can deliver good performance at low generator temperatures if the refrigerant mass fraction in the strong solution is made as high as possible. Moreover, it was shown that a H2O-LiBr working pair could be useful for achieving cooling at low generator temperatures.

Factors affecting the accuracy of control of internal combustion engine with a common rail fuel system

2020 ◽  
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Design Parameters ◽  
Repeated Injection ◽  
Fuel System ◽  
Factors Affecting ◽  
Fuel Supply ◽  
Wave Phenomena ◽  
Control Accuracy

The article presents an overview of the operation of the battery fuel system with multiple injection, as well as the factors affecting the control accuracy of an internal combustion engine with a battery fuel system. The amount of preliminary fuel supply and the delay between preliminary and subsequent fuel supply by the electrohydraulic nozzle, as well as the tolerances for the design parameters of the electrohydraulic nozzle, are considered as influencing factors. Keywords wave phenomena; repeated injection; battery fuel system; electro hydraulic injector

Implementation of Machine Learning Algorithms for Prediction of Fluidelastic Instability in Tube Arrays

2021 ◽  
Vol 143 (2) ◽  
Author(s):  
Joaquin E. Moran ◽  
Yasser Selima
Keyword(s):  
Machine Learning ◽  
Logistic Regression ◽  
Learning Algorithm ◽  
Machine Learning Algorithms ◽  
Two Phase ◽  
Factors Affecting ◽  
Logistic Regression Models ◽  
Number Of Factors ◽  
Tube Arrays ◽  
Fluidelastic Instability

Abstract Fluidelastic instability (FEI) in tube arrays has been studied extensively experimentally and theoretically for the last 50 years, due to its potential to cause significant damage in short periods. Incidents similar to those observed at San Onofre Nuclear Generating Station indicate that the problem is not yet fully understood, probably due to the large number of factors affecting the phenomenon. In this study, a new approach for the analysis and interpretation of FEI data using machine learning (ML) algorithms is explored. FEI data for both single and two-phase flows have been collected from the literature and utilized for training a machine learning algorithm in order to either provide estimates of the reduced velocity (single and two-phase) or indicate if the bundle is stable or unstable under certain conditions (two-phase). The analysis included the use of logistic regression as a classification algorithm for two-phase flow problems to determine if specific conditions produce a stable or unstable response. The results of this study provide some insight into the capability and potential of logistic regression models to analyze FEI if appropriate quantities of experimental data are available.

PORTFOLIO ANALYSIS IN THE DEVELOPMENT OF CORPORATE STRATEGY

2021 ◽  
Vol 2 (10) ◽  
pp. 13-20
Author(s):  
Ekaterina A. Egorova ◽  
◽  
Polina V. Syrovatkina ◽  
Tatiana F. Chernova ◽  
Irina S. Brikoshina ◽  
...  
Keyword(s):  
Strategic Management ◽  
Corporate Strategy ◽  
Portfolio Analysis ◽  
Point Of View ◽  
Factors Affecting ◽  
Number Of Factors ◽  
Market Situation

This article reveals the specifics of developing a corporate strategy using portfolio analysis, taking into account the current market situation, which has created a number of factors affecting labor produc-tivity, internal and external policies of organizations, using the example of the work of the "Vishnevii sad" theater. The information about portfolio analysis in the development of corporate strategy is presented from the point of view of strategic management. Both theoretical and practical data are given, including different ways of constructing portfolio analysis, rules and methods that can be implemented. Proposals for modifica-tion and improvement of internal processes taking into account the influence of extraneous factors, possible goals and results are presented.

scholarly journals Dynamic Response Analysis on the Interaction Between Flexible Bodies of Large-Sized Wind Turbine Under Random Wind Loads

2018 ◽  
Author(s):  
Yilun Li ◽  
Shuangxi Guo ◽  
Min Li ◽  
Weimin Chen ◽  
Yue Kong
Keyword(s):  
Dynamic Response ◽  
Wind Turbine ◽  
Elastic Deformation ◽  
Dynamic Interaction ◽  
Response Analysis ◽  
Flexible Bodies ◽  
Dynamic Response Analysis ◽  
Dynamic Behaviors ◽  
Energy Consuming ◽  
Turbine Model

As the output power of wind turbine increasingly gets larger, the structural flexibility of elastic bodies, such as rotor blades and tower, gets more significant owing to larger structural size. In that case, the dynamic interaction between these flexible bodies become more profound and may significantly impact the dynamic response of the whole wind turbine. In this study, the integrated model of a 5-MW wind turbine is developed based on the finite element simulations so as to carry out dynamic response analysis under random wind load, in terms of both time history and frequency spectrum, considering the interactions between the flexible bodies. And, the load evolution along its transmitting route and mechanical energy distribution during the dynamic response are examined. And, the influence of the stiffness and motion of the supporting tower on the integrated system is discussed. The basic dynamic characteristics and responses of 3 models, i.e. the integrated wind turbine model, a simplified turbine model (blades, hub and nacelle are simplified as lumped masses) and a rigid supported blade, are examined, and their results are compared in both time and frequency domains. Based on our numerical simulations, the dynamic coupling mechanism are explained in terms of the load transmission and energy consumption. It is found that the dynamic interaction between flexible bodies is profound for wind turbine with large structural size, e.g. the load and displacement of the tower top gets around 15% larger mainly due to the elastic deformation and dynamic behaviors (called inertial-elastic effect here) of the flexible blade; On the other hand, the elastic deformation may additionally consume around 10% energy (called energy-consuming effect) coming from external wind load and consequently decreases the displacement of the tower. In other words, there is a competition between the energy-consuming effect and inertial-elastic effect of the flexible blade on the overall dynamic response of the wind turbine. And similarly, the displacement of the blade gets up to 20% larger because the elastic-dynamic behaviors of the tower principally provides a elastic and moving support which can significantly change the natural mode shape of the integrated wind turbine and decrease the natural frequency of the rotor blade.

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