Experimental Validation of Passenger Car Underhood Simulation in the Presence of Convective and Radiative Heat Flux

Author(s):  
Daniele Suzzi ◽  
Bernhard Lechner ◽  
Christian Rauch ◽  
Sebastian Jagsch ◽  
Raimund Almbauer

The numerical prediction of underhood local temperatures represents a challenging field in the development of passenger cars. The reliability of computational fluid dynamics (CFD) results is depending upon numerics and employing appropriate physical models which can strongly affect the quality of results and the overall simulation time. The purpose of this paper is to analyze and validate the simulation of heat transfer phenomena in a vehicle’s underbody through the comparison with experimental data. The measurements are obtained from thermal sensors mounted on a passenger car during a highway drive. Furthermore, the radiative boundary conditions are defined through the post-processing of thermographic camera images. The numerical results of a commercial CFD code are finally compared with the experimental data on surface temperatures of the vehicle’s underbody.

Transport ◽  
2016 ◽  
Vol 31 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Orazio Giuffrè ◽  
Anna Granà ◽  
Sergio Marino ◽  
Fabio Galatioto

Due to its geometric design, turbo-roundabouts impose greatest constraints to the vehicular trajectories; by consequence, one can expect a more unfavourable impact of heavy vehicles on the traffic conditions than on other types of roundabouts. The present paper addresses the question of how to estimate Passenger Car Equivalents (PCEs) for heavy vehicles driving turbo-roundabouts. The microsimulation approach used revealed as a useful tool for evaluating the variation of quality of traffic in presence of mixed fleets (different percentages of heavy vehicles). Based on the output of multiple runs of several scenarios simulation, capacity functions for each entry lane of the turbo-roundabout were developed and variability of the PCEs for heavy vehicles were calculated by comparing results for a fleet of passenger cars only with those of the mixed fleet scenarios. Results show a dependence of PCEs for heavy vehicles on operational conditions, which characterise the turbo-roundabout. Assuming the values of PCEs for roundabouts provided by the 2010 Highway Capacity Manual (HCM), depending on entering manoeuvring underestimation and overestimation of the effect of heavy vehicles on the quality of traffic conditions have been found.


2017 ◽  
Vol 76 (6) ◽  
pp. 323-328 ◽  
Author(s):  
A. V. Komissarov ◽  
E. A. Zubkova ◽  
E. G. Krokhaleva ◽  
M. A. Evgen’Eva ◽  
N. B. Karavanova ◽  
...  

Steady requirements of consumers to the quality of to the development of automated systems, make it necessary to the information provided, on the basis of which the control actions constantly process or create higher quality products. The require-are carried out, as well as the acceleration of technical means related ment to improve the basic information solutions using modern technical resources offered by industry was the reason for the rework of the existing business process for managing the fleet of passenger cars implemented in the automated system for managing operation and repair of the passenger car fleet (ASUPV). The article gives a brief analysis of the 20-year work of the linear enterprises (LP) with the ASUPV - (ASUPV LP) subsystem, with the help of which the source documents are entered into the car park, trains are formed and the passenger car fleet maintenance is monitored. This subsystem is the main supplier of information for obtaining analytical data at all levels of passenger car fleet management. The article also outlines the main goal of the new information technology - obtaining, through single processing of primary data, new quality information, on the basis of which optimal management solutions should be developed. The purpose of the newly developed ASUPV LP-2 system is to automate the technological processes of centralized management of the passenger fleet of linear enterprises to improve performance and efficiency of the industry, which will allow optimizing the work of passenger line enterprises, monitoring compliance with technological processes and ensuring the availability of reliable information to interested users. The article describes the main tasks of the developed system: ensuring the need for the necessary and sufficient number of passenger cars for the fulfillment of the transportation plan at the linear enterprise; creating of guaranteed traffic safety of the formed passenger trains; improving the quality of repairs and maintenance. It is noted that the sources of increased complexity of managing the passenger car fleet are the constantly increasing complexity of business processes automated at the linear enterprise, which conflicts with the existing regulatory and technological base, as well as increasing requirements for the speed and accuracy of execution of all operations with cars. It is also indicated that automatic monitoring of the input sequence of source documents and its information interconnection should be created in the developed system and a system of automated control and prevention of conscious violations performed by users should be developed in order to improve the performance of their own work. The system should control the user's actions as much as possible and check the information entered by the user for compliance with regulatory requirements.


Author(s):  
Sang-Kwon Lee ◽  
Byung-Soo Kim ◽  
Dong-Chul Park

A rumbling sound is one of the most important sound qualities in a passenger car. In previous work, a method for objectively evaluating the rumbling sound was developed based on the principal rumble component. In the present paper, the rumbling sound was found to relate effectively not only to the principal rumble component but also to the loudness and roughness. The last two subjective parameters are sound metrics in psychoacoustics. The principal rumble component, roughness, and loudness were used as the sound metrics for the development of the rumbling index to evaluate the rumbling sound objectively. The relationship between the rumbling index and these sound metrics is identified by an artificial neural network. Interior sounds of 14 passenger cars were measured, and 21 passengers subjectively evaluated the rumbling sound qualities of these interior sounds. Through this research, it was found that the results of these evaluations and the output of a neural network have a high correlation. The rumbling index has been successfully applied to the objective evaluation of the rumbling sound quality of mass-produced passenger cars.


2011 ◽  
Vol 52-54 ◽  
pp. 144-147
Author(s):  
Bing Chen Zhang ◽  
Wei Min Guo ◽  
Yan Qun Wang

The development of interior design is an important aspect of improving the quality of railway transportation services. Product semantics not only pay attention to the physiology function, but also go deep into psychology function. The core of semantics communication is encoding rule. It would ensure the two basic processes that encoding and decoding go smoothly in semantics communication. Thus it would improve the interior system design of the railway passenger cars effectively that paying attention to the characteristics of encoding rules.


2010 ◽  
Vol 44-47 ◽  
pp. 1554-1557
Author(s):  
Bing Chen Zhang ◽  
Wei Min Guo ◽  
Yan Qun Wang

The development of interior design is an important aspect of improving the quality of railway transportation services. The interior design system of the railway passenger cars may do better in reflecting the interrelations among the passengers, the facilities and the environment of the compartments with the harmony idea to considerate relationship between the passengers, the facilities and the environment. In this way, we may have the optimized performance of the interior system and improve the interior system design of the railway passenger car effectively.


Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.


Author(s):  
D.I. Engalychev ◽  
N.A. Engalycheva ◽  
A.M. Menshikh

Представлены экспериментальные данные о влиянии капельного орошения на урожайность и качество плодов томата при выращивании культуры в открытом грунте Московской области. На плодородных аллювиальных луговых почвах Москворецкой поймы при соблюдении агротехники без орошения в среднем за три года исследований в полевых условиях получена урожайность томата F1 Донской 31,9 т/га, с орошением 48,5 т/га, в т.ч. стандартной продукции 42,6 т/га.The article presents experimental data on the effect of drip irrigation on the yield and quality of tomato fruits when growing crops in open ground of the Moscow Region. On fertile alluvial meadow soils of the Moscow river floodplain, with the observance of agricultural technology without irrigation, the field yield of tomato hybrid F1 Donskoi on average for three years of research was 31.9 t/ha, with irrigation 48.5 t/ha, incl. standard production 42.6 t/ha.


2019 ◽  
Author(s):  
Liwei Cao ◽  
Danilo Russo ◽  
Vassilios S. Vassiliadis ◽  
Alexei Lapkin

<p>A mixed-integer nonlinear programming (MINLP) formulation for symbolic regression was proposed to identify physical models from noisy experimental data. The formulation was tested using numerical models and was found to be more efficient than the previous literature example with respect to the number of predictor variables and training data points. The globally optimal search was extended to identify physical models and to cope with noise in the experimental data predictor variable. The methodology was coupled with the collection of experimental data in an automated fashion, and was proven to be successful in identifying the correct physical models describing the relationship between the shear stress and shear rate for both Newtonian and non-Newtonian fluids, and simple kinetic laws of reactions. Future work will focus on addressing the limitations of the formulation presented in this work, by extending it to be able to address larger complex physical models.</p><p><br></p>


2012 ◽  
Vol 512-515 ◽  
pp. 2135-2142 ◽  
Author(s):  
Yu Peng Wu ◽  
Zhi Yong Wen ◽  
Yue Liang Shen ◽  
Qing Yan Fang ◽  
Cheng Zhang ◽  
...  

A computational fluid dynamics (CFD) model of a 600 MW opposed swirling coal-fired utility boiler has been established. The chemical percolation devolatilization (CPD) model, instead of an empirical method, has been adapted to predict the nitrogen release during the devolatilization. The current CFD model has been validated by comparing the simulated results with the experimental data obtained from the boiler for case study. The validated CFD model is then applied to study the effects of ratio of over fire air (OFA) on the combustion and nitrogen oxides (NOx) emission characteristics. It is found that, with increasing the ratio of OFA, the carbon content in fly ash increases linearly, and the NOx emission reduces largely. The OFA ratio of 30% is optimal for both high burnout of pulverized coal and low NOx emission. The present study provides helpful information for understanding and optimizing the combustion of the studied boiler


2015 ◽  
Vol 43 (1) ◽  
pp. 399-411 ◽  
Author(s):  
Michael Ringenburg ◽  
Adrian Sampson ◽  
Isaac Ackerman ◽  
Luis Ceze ◽  
Dan Grossman
Keyword(s):  

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