A Numerical Investigation of Automobile Environment Through Cooling Period and Condensation

2009 ◽  
Author(s):  
Md. Faisal Kader ◽  
Kang Hyu Goo ◽  
Yong-Du Jun ◽  
Kum-Bae Lee
Keyword(s):  
Fluid Flow ◽  
Initial Period ◽  
Three Dimensional ◽  
Practical Significance ◽  
Scale Model ◽  
Design Parameters ◽  
Experimental Investigations ◽  
Three Dimensional Model ◽  
Cooling Period ◽  
Initial Stage

Understanding the fluid flow and heat transfer characteristics within a vehicle compartment is very important for controlling the effect of major design parameters. Also, adequate visibility through the vehicle windshield over the entire driving period is of paramount practical significance. The numerical solution was done by an operation friendly, fast and accurate CFD code — SC/Tetra with a full scale model of a SM3 car and turbulence was modeled by the standard k-ε equation. Numerical analysis of the three-dimensional model predicts a detailed description of fluid flow and temperature distribution in the passenger compartment and on the inside windshield screen. During the cooling period, the lowest temperature is observed in the lower part of the windshield and in the vicinity of the defroster griller. It was found that the temperature dropped down to a comfortable range almost linearly at the initial stage. The initial period to achieve this comfortable range is dependent on the inlet velocity. Experimental investigations are performed to determine the localized thermal comfort and further validation of the numerical results.

A Numerical Study of Natural Convection Inside an Automobile Compartment Due to Solar Radiation

2009 ◽  
Author(s):  
Md. Faisal Kader ◽  
Yong-du Jun ◽  
Kum-bae Lee
Keyword(s):  
Fluid Flow ◽  
Solar Radiation ◽  
Numerical Study ◽  
Three Dimensional ◽  
Scale Model ◽  
Design Parameters ◽  
Three Dimensional Model ◽  
Flow And Heat Transfer ◽  
Flow Through ◽  
Paper Address

In summer, the temperature of a parked automobile compartment increases extremely high under a sunny condition. Investigation of this fluid flow and heat transfer characteristics is very important for controlling the effect of major design parameters. This paper address the behavior of fluid flow through convection and air temperature inside a car parked in the sun. The numerical solution was done by a new and operation friendly CFD code – SC/Tetra with a full scale model of a SM3 car and turbulence was modeled by the standard k-ε equation. It can be seen that solar radiation is an important parameter to raise the compartment temperature above the ambient temperature during summer. Numerical analysis of the three-dimensional model predicts a detailed description of fluid flow and temperature distribution driven by the incoming solar radiation (insoaltion) in the passenger compartment.

Numerical Analysis of Automobile Environment During the Cooling Period in Summer

2008 ◽  
Author(s):  
Kum-Bae Lee ◽  
Md. Faisal Kader ◽  
Young-Muk Youn
Keyword(s):  
Three Dimensional ◽  
Considerable Change ◽  
Practical Significance ◽  
Instrument Panel ◽  
Shelf Area ◽  
Cooling Period ◽  
Initial Stage ◽  
Temperature And Humidity ◽  
Humidity Profiles ◽  
Good Agreement

Understanding the temperature and humidity profiles inside a vehicle when the A/C is on during summer is of paramount practical significance to maintain comfortable environment. In this paper, the airflow patterns, temperature and humidity distributions are predicted utilizing a three-dimensional finite volume numerical method and measured experimentally inside the automobile. Numerical analyses of the three-dimensional geometry predict a detailed description of fluid flow patterns. The velocity vectors from the side instrument panel registers impinge on the front occupant’s chest to head then travel forward and finally reach to the rear parcel shelf area. The undesirable returning flow passing by the driver’s head and neck has been observed. The velocity vectors from the central instrument panel registers travel directly to the rear compartment. A recirculation has been observed near the occupant’s knee area of the front compartment and rear compartment. The Temperature comes down to a comfortable range almost linearly at the initial stage. After that no considerable change has been observed. A good agreement has been found between the numerical and experimental results.

scholarly journals Research on the Computed Tomography Pebble Flow Detecting System for HTR-PM

2017 ◽  
Vol 2017 ◽  
pp. 1-13
Author(s):  
Xin Wan ◽  
Ximing Liu ◽  
Jichen Miao ◽  
Peng Cong ◽  
Yuai Zhang ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Helical Ct ◽  
Design Parameters ◽  
Three Dimensional Model ◽  
Safe Operation ◽  
Cross Sectional ◽  
Ct System ◽  
Near Future ◽  
Pebble Flow

Pebble dynamics is important for the safe operation of pebble-bed high temperature gas-cooled reactors and is a complicated problem of great concern. To investigate it more authentically, a computed tomography pebble flow detecting (CT-PFD) system has been constructed, in which a three-dimensional model is simulated according to the ratio of 1 : 5 with the core of HTR-PM. A multislice helical CT is utilized to acquire the reconstructed cross-sectional images of simulated pebbles, among which special tracer pebbles are designed to indicate pebble flow. Tracer pebbles can be recognized from many other background pebbles because of their heavy kernels that can be resolved in CT images. The detecting principle and design parameters of the system were demonstrated by a verification experiment on an existing CT system in this paper. Algorithms to automatically locate the three-dimensional coordinates of tracer pebbles and to rebuild the trajectory of each tracer pebble were presented and verified. The proposed pebble-detecting and tracking technique described in this paper will be implemented in the near future.

Digitalization of production in Altium Designer software

2021 ◽  
pp. 34-42
Author(s):  
S. S. Yudachev ◽  
S. S. Sitnikov ◽  
F. M. Bosy
Keyword(s):  
Printed Circuit Boards ◽  
Electronic Device ◽  
Educational Institution ◽  
Three Dimensional ◽  
Electrical Circuit ◽  
Circuit Board ◽  
Practical Significance ◽  
Three Dimensional Model ◽  
Printed Circuit ◽  
Higher Educational

A method for modeling and printed circuit board layout in the form of a 3D model in one of the digital solutions designed for this task, Altium Designer, is proposed. The practical significance of the work is the study of the basic software libraries in terms of their creation, filling and application when working with the project, as well as of the algorithm for constructing an electrical circuit in the Altium Designer program, layout and design of the simplest circuit on the board. In the course of the work, the algorithm and rules for creating a library of three-dimensional models of components, a library containing conditional graphic designations of the corresponding components, a schematic diagram of the device, a three-dimensional model of the board and the construction of conducting tracks on it are described. The components and circuits used in the work are publicly available on the Internet, which allows anyone to work over the entire algorithm for studying and honing the skills of designing printed circuit boards, both by students studying at a higher educational institution and by fully-fledged specialists. This work can be used not only for teaching students in the field of electronic device development in terms of their design and for organizing laboratory work, but also for creating and designing real devices both in production and within a higher educational institution, for example, for creating a laboratory bench. The introduction and study of this software is carried out at the Department of Radio-Electronic Systems and Complexes of one of the leading engineering universities of the Russian Federation — the Bauman Moscow State Technical University.

Development and validation of a novel quasi-dimensional combustion model for un-scavenged prechamber gas engines with numerical simulations and engine experiments

2020 ◽  
pp. 146808742095133 ◽  
Author(s):  
Konstantinos Bardis ◽  
Panagiotis Kyrtatos ◽  
Guoqing Xu ◽  
Christophe Barro ◽  
Yuri Martin Wright ◽  
...  
Keyword(s):  
Numerical Simulations ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Design Parameters ◽  
Combustion Model ◽  
Experimental Investigations ◽  
Computationally Efficient ◽  
Lean Burn ◽  
Dimensional Models ◽  
Three Dimensional Models

Lean-burn gas engines equipped with an un-scavenged prechamber have proven to reduce nitrogen oxides (NOx) emissions and fuel consumption, while mitigating combustion cycle-to-cycle fluctuations and unburned hydrocarbon (UHC) emissions. However, the performance of a prechamber gas engine is largely dependent on the prechamber design, which has to be optimised for the particular main chamber geometry and the foreseen engine operating conditions. Optimisation of such complex engine components relies partly on computationally efficient simulation tools, such as quasi and zero-dimensional models, since extensive experimental investigations can be costly and time-consuming. This article presents a newly developed quasi-dimensional (Q-D) combustion model for un-scavenged prechamber gas engines, which is motivated by the need for reliable low order models to optimise the principle design parameters of the prechamber. Our fundamental aim is to enhance the predictability and robustness of the proposed model with the inclusion of the following: (i) Formal derivation of the combustion and flow submodels via reduction of the corresponding three-dimensional models. (ii) Individual validation of the various submodels. (iii) Combined use of numerical simulations and experiments for the model validation. The resulting model shows very good agreement with the numerical simulations and the experiments from two different engines with various prechamber geometries using a set of fixed calibration parameters.

Blast load simulation using conical shock tube systems

2019 ◽  
Vol 11 (2) ◽  
pp. 135-158 ◽  
Author(s):  
Ahmed Ismail ◽  
Mohamed Ezzeldin ◽  
Wael El-Dakhakhni ◽  
Michael Tait
Keyword(s):  
Shock Tube ◽  
Three Dimensional ◽  
Design Parameters ◽  
Civil Infrastructure ◽  
Two Dimensional ◽  
Blast Loads ◽  
Dimensional Model ◽  
Tube System ◽  
Three Dimensional Model ◽  
Conical Shock

With the increased frequency of accidental and deliberate explosions, evaluating the response of civil infrastructure systems to blast loading has been attracting the interests of the research and regulatory communities. However, with the high cost and complex safety and logistical issues associated with field explosives testing, North American blast-resistant construction standards (e.g. ASCE 59-11 and CSA S850-12) recommend the use of shock tubes to simulate blast loads and evaluate relevant structural response. This study first aims at developing a simplified two-dimensional axisymmetric shock tube model, implemented in ANSYS Fluent, a computational fluid dynamics software, and then validating the model using the classical Sod’s shock tube problem solution, as well as available shock tube experimental test results. Subsequently, the developed model is compared to a more complex three-dimensional model and the results show that there is negligible difference between the two models for axisymmetric shock tube performance simulation; however, the three-dimensional model is necessary to simulate non-axisymmetric shock tubes. Following the model validation, extensive analyses are performed to evaluate the influences of shock tube design parameters (e.g. the driver section pressure and length and the expansion section length) on blast wave characteristics to facilitate a shock tube design that would generate shock waves similar to those experienced by civil infrastructure components under blast loads. The results show that the peak reflected pressure increases as the driver pressure increases, while a decrease in the expansion length increases the peak reflected pressure. In addition, the positive phase duration increases as both the driver length and expansion length are increased. Finally, the developed two-dimensional axisymmetric model is used to optimize the dimensions of a physical large-scale conical shock tube system constructed for civil infrastructure component blast response evaluation applications. The capabilities of such shock tube system are further investigated by correlating its design parameters to a range of explosion threats identified by different hemispherical TNT charge weight and distance scenarios.

scholarly journals Simulation Technique of Kinematic Processes in the Vehicle Steering Linkage

2018 ◽  
Vol 7 (4.3) ◽  
pp. 120 ◽  
Author(s):  
Sergii Chernenko ◽  
Eduard Klimov ◽  
Andrii Chernish ◽  
Olexandr Pavlenko ◽  
Volodymyr Kukhar
Keyword(s):  
Three Dimensional ◽  
Simulation Technique ◽  
Design Parameters ◽  
Three Dimensional Model ◽  
Design Data ◽  
Power Characteristics ◽  
Left And Right ◽  
Turning Radius ◽  
The Impact ◽  
The Mathematical Model

The results of the investigation of the turning kinematics of the steerable wheels of the KrAZ-7634NE off-road vehicle with a wheel formula 8x8 and two front steer axles are given. The theoretical relations between the steer angles of the steerable wheels on the basis of the scheme of double-axle steering turning of the vehicle are shown. The mathematical model of flat four-bar vehicle steering linkage is developed, it determines the relation between the steering linkage left and right steering arms turning angles at any turning radius of the vehicle. KrAZ-7634HE steering three-dimensional model was created and simulation technique of its work was carried out using Creo software. It has been shown that the flat steering linkage model provides sufficient accuracy of calculations in analysis of turning kinematics. The design data can be used for any vehicles that have a similar steering linkage, they allow to analyze the impact of the vehicle design parameters on the turning kinematics and optimize them. Further study of the impact of the kingpin inclinations on the steering linkage kinematic and power characteristics are required.  

Microscale fluid flow analysis in a human osteocyte canaliculus using a realistic high-resolution image-based three-dimensional model

2012 ◽  
Vol 4 (10) ◽  
pp. 1198-1206 ◽  
Author(s):  
Hiroshi Kamioka ◽  
Yoshitaka Kameo ◽  
Yuichi Imai ◽  
Astrid D. Bakker ◽  
Rommel G. Bacabac ◽  
...  
Keyword(s):  
Fluid Flow ◽  
High Resolution ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Resolution Image ◽  
High Resolution Image ◽  
Fluid Flow Analysis

A note on three-dimensional turbulence and evaporation in the lower atmosphere

1950 ◽  
Vol 202 (1068) ◽  
pp. 96-103 ◽  
Keyword(s):  
Three Dimensional ◽  
Lower Atmosphere ◽  
Practical Significance ◽  
Dimensional System ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Mathematical Relationship ◽  
Dimensional Diffusion ◽  
Lateral Extent ◽  
The Relationship

In view of the practical significance in dynamical meteorology of the problem of evaporation from areas of finite lateral extent, it is a matter of fundamental importance to test as fully as possible the applicability of the hypothetical three-dimensional model of turbulence which was introduced by the author in 1947. The present paper describes in detail the manner in which the two-dimensional system developed by O. G. Sutton, K. L. Calder and E. L. Deacon for flow over aerodynamically smooth and rough surfaces may be extended to three-dimensional diffusion of vapour over an evaporating area. The agreement obtained between theory and experiment is good at points over the area. This agreement indicates that the assumed law, introduced by the author to give the variation of the coefficient of lateral diffusivity with height above the surface, may be used satisfactorily in evaporation problems as long as attention is confined to points not too far outside the boundaries of the area. The complicated mathematical relationship previously obtained for the vapour distribution vertically above the down-wind edge of a parabolic strip is reduced to a much simpler one. This serves to bring out explicitly the relationship between the effects of the two- and three-dimensional theoretical systems of turbulent transfer at points on the central axis of the area.

Research on Automobile Coupled Vibration between Transmission Shaft and Drive Axle Gears

2014 ◽  
Vol 915-916 ◽  
pp. 76-81 ◽  
Author(s):  
Jin Li Xu ◽  
Lei Lu ◽  
Xing Sheng Cao ◽  
Bo Wei
Keyword(s):  
Three Dimensional ◽  
Design Parameters ◽  
Coupled Vibration ◽  
Dynamics Model ◽  
Three Dimensional Model ◽  
Coupling Vibration ◽  
Transmission Shaft ◽  
Body Dynamics ◽  
Flexible Body Dynamics ◽  
Drive Axle

Coupled vibration between transmission shaft and drive axle gears is one of the main factors influencing NVH in the FR transmission system. Based on the transmission shaft and drive axle gears, using UG to establish three-dimensional model, establishing flexible-body dynamics model and solving coupling vibration laws of transmission shaft and drive axle gears by ADAMS, and analyzing influencing factors on coupled vibration between transmission shaft and drive axle gears.It is of theoretic significance, for design parameters and installation matching between transmission shaft and drive axle gears.

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