Adrian Clenci

Adrian Clenci
University of Pitesti · Department Automobiles and Transport

Professor habil. dr. ing.
Automotive Engineering, Sustainable road mobility

About

107
Publications
50,195
Reads
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377
Citations
Citations since 2016
64 Research Items
292 Citations
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20162017201820192020202120220102030405060
20162017201820192020202120220102030405060
Introduction
Adrian Clenci is Full Professor at the Dept. Automobiles and Transport, University of Pitesti (UPIT). He was the President of the Romanian SAE between 2012 and 2020. From 2008 to 2020 he was Associated Researcher at CNAM Paris. Currently he is the ViceRector in charge with Scientific Research at UPIT. Since 1996, teaching and research in the field of Sustainable Road Mobility: Variable Compression Ratio, Variable Valve Actuation, Miller-Atkinson Cycle, CFD Simulation, Alternative fuels.
Additional affiliations
February 2019 - present
University of Pitesti
Position
  • Professor (Full)
October 2017 - present
University of Pitesti
Position
  • HDR or Habilitation to conduct scientific research
Description
  • Scientific Advisor for PhD students
October 2011 - October 2019
University of Pitesti
Position
  • Managing Director
Education
October 1997 - October 2003
Universitatea Transilvania Brasov
Field of study
  • Mechanical Engineering
October 1996 - July 1997
University of Pitesti
Field of study
  • Automotive Engineering
October 1991 - July 1996
University of Pitesti
Field of study
  • Automotive Engineering

Publications

Publications (107)
Article
Full-text available
Currently, turbocharged common rail high pressure direct injection diesel engines are regarded as state-of-the-art. The use of the turbocharging technique in gasoline engines is also increasing, in order to achieve further fuel consumption reductions via downsizing. As the specific power outputs of both diesel and gasoline engines rise, the low-end...
Article
Full-text available
The inefficient running of the spark ignition engine at part loads due to the load control method but, mostly, their major weighting in the vehicle's operation time justifies the interest in the technical solutions, which act in this particular operating range. These drawbacks encountered at low part loads are even more amplified when considering l...
Article
Full-text available
Reducing fuel consumption is a prime objective in the automotive industry in order to meet regulatory and customer demands. Variable valve actuation offers many opportunities for improving the spark ignition engine's performance in areas such as fuel economy and pollutant emissions. Our studies revealed that the ability to control maximum intake va...
Article
Full-text available
Reducing fuel consumption is a prime objective in order to meet regulatory and customer demands. Given this context, an original port fuel injected engine featuring variable valve actuation was initially investigated when operating at idle with low intake valve lift. An improvement of both fuel economy and engine cycle-to-cycle variability was reco...
Article
Full-text available
Future passenger cars must comply with whatever regulations will be created to mitigate greenhouse gas emissions (GHG) and pollution. Regarding the pollutants of an internal combustion (IC) engine, they are dealt with by using an exhaust after-treatment system (EATS). Yet, catalytic converters encounter light-off problems after cold start: their af...
Article
Full-text available
This paper assesses the effect of the Miller cycle upon the internal aerodynamics of a motored transparent spark ignition engine via CFD simulation and particle image velocimetry. Since the transparent Miller engine does not allow for measurements in the roof of the combustion chamber, the extraction of information regarding the aerodynamic phenome...
Article
Given the increased concern for environmental protection and the need for finding viable alternatives for replacing fossil fuels in internal combustion engines, the research carried out in the recent past on the use of biodiesel has increased. Out of the physico-chemical characteristics of fuels, the volatility has a great influence on the combusti...
Article
Full-text available
The article presents the results of a 1D numerical simulation of a spark ignition engine developed to operate in Miller cycle. Miller cycle offers better thermal efficiency compared to Otto cycle due to higher volumetric expansion than compression, which in the current context is of paramount importance. In an engine with fixed geometric compressio...
Article
Full-text available
Surge is an unstable phenomenon appearing when a valve closing reduces the compressor flow rate. This phenomenon is avoided for automotive turbochargers by defining a surge margin during powertrain system design. This surge margin established with measurements in steady state testing regime limits the maximal engine torque at low levels of output....
Article
Full-text available
The lubricating oil fulfills several purposes, such as: reducing friction processes, protecting the parts of the engine mechanism from wear, preventing the occurrence of corrosion phenomena, taking over and transporting or transferring impurities to the oil filter, lubricating the moving parts as well as their cooling. The lubrication fluid of the...
Conference Paper
Full-text available
As argued in many papers, from the road mobility point of view, today, there are three major problems facing humanity: (1) greenhouse gas (GHG) emissions, global warming and city pollution; (2) renewable or sustainable sources of energy; and (3) energy security. The above listed 3 problems generated intense discussions at international level on the...
Preprint
Full-text available
Today, the greenhouse gas (GHG) emissions (specifically, CO2) represent the greatest challenge of the internal combustion (IC) engine and consequently, now, more than ever, the passenger car industry is looking for technologies meant to address this issue. Since CO2 emission is related to the combustion process occurring inside the engine, its redu...
Article
Full-text available
Termenii care au determinat scrierea acestui articol sunt concepție și proiectare. Sunt sau nu sinonimi? Dacă nu, atunci ce-i distinge, care sunt nuanțele ce îi diferențiază? Iată, deci, câteva întrebări cărora vom încerca să le găsim răspuns în acest articol http://siar.ro/wp-content/uploads/2021/06/rIA59.pdf
Article
Full-text available
Assessment of the impact of the intake valve masking and piston stroke increasing on the Miller engine’s internal aerodynamics In order to comply with the future emissions regulations, at this point, it seemed that more and more automotive manufacturers will use the Miller over-expanded cycle. In our past research, we highlighted the fact that the...
Article
Full-text available
https://automotive.upit.ro/ - Open Access Journal of University of Pitesti Scientific Bulletin - Automotive Series As air pollution and global warming become a priority in sustainable mobility, the evolution of vehicles is facing many regulations that are becoming increasingly stringent in terms of reducing greenhouse gas (GHG) emissions, forcing...
Article
Full-text available
https://automotive.upit.ro University of Pitesti, Scientific Bulletin - Automotive Series (open access journal) https://automotive.upit.ro/index_files/2021/2021_5_.pdf "Temporary downsizing" in the form of deactivation of the cylinders is used as an attractive compromise, as it allows to improve fuel consumption and at the same time, it allows suf...
Article
Full-text available
The automotive electric supercharger provides high torque at low engine speeds. During accelerations, it fills the power gap due to the turbocharger’s inertia and avoids turbo lag. Its operation is of short duration because once this deficit has been juggled, it must be stopped in order not to generate unnecessary electricity consumption and to avo...
Article
Full-text available
Termenul pe care-l aducem acum în discuție este șasiu cu variantele (mai mult sau mai puțin) echivalente din franceză (châssis), engleză (chassis), germană (Chassis, Fahrwerk). După cum vom arăta, folosirea acestui termen generează, uneori, confuzie. Acesta este motivul pentru care am decis abordarea sa.
Chapter
https://www.techniques-ingenieur.fr/base-documentaire/mecanique-th7/combustion-dans-les-moteurs-thermiques-et-environnement-4216621
Article
Full-text available
Termenul care face obiectul analizei în numărul de faţă al publicaţiei este cel de demaraj/ demarare, care va fi explorat atât individual cât şi ca parte a sintagmei rezistenţa la demaraj/ demarare, noţiune care suscită interes atât ştiinţific cât şi didactic în domeniul ingineriei autovehiculelor. Am încercat, mai întâi, să răspundem întrebării da...
Chapter
Currently, the internal combustion engine is facing tough regulations regarding pollution and CO2. In order to comply with the latest constraints concerning the CO2 emission, the automotive manufacturers must increase the thermal efficiency of the combustion engine. One way which seems to be preferential for the manufacturers is to implement the Mi...
Article
Full-text available
Rubrica noastră continuă... În numărul actual, am discutat despre driv(e)ability, un termen foarte cunoscut, foarte uzitat în limba engleză și, foarte frecvent, preluat ca atare și în limba română. Driv(e)ability (en) - Agrément de conduite (fr) - Fahrbarkeit (ger) - Draivabilitate (ro)
Article
Full-text available
The tightening of pollution and greenhouse gas regulations generated a change in the homologation procedure, i.e., a far more dynamic driving cycle and the testing of the vehicle in real driving conditions are now part of the type approval procedure. In order to cope with these new challenges, the car manufacturers must adopt new technologies such...
Presentation
Full-text available
I made this presentation at the Engineering Trainers' Convention at Renault Bucharest Convention (RBC). Its first part is about what the "superpowers" of a trainer/professor/teacher/educator/instructor are. The second part is about: - the complexity of Automotive Engineering Education nowadays, - the widening gap between industry needs for multi...
Book
Full-text available
Se prezinta evolutia Facultatii de Mecanica si Tehnologie din cadrul Universitatii din Pitesti: educatie, cercetare stiintifica, legatura cu mediul socio-economic
Presentation
Full-text available
Facem suficient? Se poate mai mult? Ne asumam cu responsabilitate calitatea absolventilor nostri? Prezentarea este de fapt un mic pretext pentru a initia o dezbatere mai ampla... Feedforward vs. Feedback Open loop vs. Closed loop
Article
Full-text available
The use of alternative fuels contributes to the lowering of the carbon footprint of the internal combustion engine. Biofuels are the most important kinds of alternative fuels. Currently, thanks to the new manufacturing processes of biofuels, there is potential to decrease greenhouse gas (GHG) emissions, compared to fossil fuels, on a well-to-wheel...
Presentation
Full-text available
Joint presentation (University of Pitesti and Renault Technologie Roumanie) at Romanian Automotive Industry Forum, Craiova
Article
Full-text available
Rubrica noastră continuă... Există în industria automobilelor un concept tehnic de o complexitate aparte, întrucât mobilizează, pe lângă datele ştiinţifice, obiective specifice domeniului tehnologiei, un ansamblu de operaţii, informaţii şi procese de largă subiectivitate. Este vorba despre conceptul redat prin termenul englezesc harshness. Asadar...
Book
Full-text available
Chapter
Increased environmental awareness and depletion of fossil petroleum resources are driving the automotive industry to seek out and use alternative fuels. The most eminent alternative fuels for replacing fossil fuels in internal combustion engines are biofuels (biodiesel and bioethanol).
Article
An engine faulty operation may be the result of improper use of fuels and lubricants, fact that can conduct to a decrease in lubricating characteristics and oil protection. Technical inspection of an engine is important step that cannot be postponed and it is considered an obligatory process in the warranty period, but especially post - warranty...
Book
Full-text available
Lucrarea de faţă este complementară cursurilor universitare de „Termotehnică” şi „Motoare Termice” şi este destinată, mai degrabă, studenţilor programelor de licenţă „Autovehicule Rutiere” şi „Ingineria Transporturilor și a Traficului”. Ea este o sinteză a reflecțiilor autorilor generate de activitățile din acest domeniu derulate la Universitatea d...
Article
Full-text available
Numărul de faţă al publicaţiei va aduce în discuţie termenul utilizat în limba română pentru a reda piesa monobloc căreia îi corespunde în limba franceză sintagma carter semelle, iar în limba engleză bedplate. Deci: carter semelle (fr) - bedplate (en) - semela (ro)
Article
Full-text available
On vehicles equipped with a turbocharged engine, there is a risk of compressor surge. This surge generates instabilities that lead to driving inconvenience, or even mechanical failure of the supercharging system. In general, the surge appears rather in transient operation: sudden closing of the throttle valve on gasoline engine, regulation of the E...
Preprint
Full-text available
Among many other professions, automotive engineering has significantly evolved in the past couple of decades and is constantly changing to meet the society needs of the 21st Century. As a simple example, what is today "an ordinary car"? In general, a common person using a car for his/her own needs doesn't think at its complexity at the amount of "w...
Data
This page presents the RCR map (i.e., the values of real compression ratio for the whole engine’s operating area) obtained with the method presented in the paper entitled "On the compression ratio definition".
Article
Full-text available
Termenul supus discuţiei în prezenta lucrare se referă la o componentă din structura motoarelor cu ardere internă, care în limba franceză corespunde substantivului linguet, iar în limba engleză sintagmelor echivalente end pivot rocker arm sau finger follower. Deci: linguet (fr) - end pivot rocker arm (en) sau finger follower (en) - langheta (ro)
Chapter
This article first gives a brief review of heat engines designed for terrestrial transportation since the 1900s. We then outline the main developments in the state of the art and knowledge about internal combustion engines, focusing on the increasingly stringent pollution constraints imposed since the 1990s. The general concept of high-energy perfo...
Presentation
Full-text available
Plenary presentation at COFRET2018, Strasbourg, 28-29.06.2018
Research Proposal
Full-text available
The goal of the study is related to the design of the automotive engineering curriculum in relation to: - what kind of mathematics should be taught to automotive students? - how can be achieved an optimal integration of the math contents with those of the automotive thermodynamics, gas dynamics, vehicle dynamics, etc? - how can teaching and learni...
Presentation
Full-text available
Conférencier invité au 19e cycle de conférences "Utilisation rationnelle de l'énergie et environnement", Le Cnam Paris
Article
Full-text available
In acest prim articol pe subiectul terminologiei s-au abordat patru termeni de bază ai domeniului Ingineria Autovehiculelor: autovehicul, automobil, autoturism, vehicul
Book
Full-text available
Given that automobiles and their engines are designed to operate in different conditions, getting the right performance and reliability depend on both the technological factors related to their manufacture and the quality of used fuels. So, it is necessary to present the physico-chemical properties of the fuels in accordance with the performances o...
Article
Full-text available
The European Commission approved a so-called Real Driving Emission (RDE) test in response to the criticisms to the current driving cycle used at chassis dyno for homologation purpose (NEDC): it is considered outdated and misleading since air pollutants in real driving conditions are considerably higher than the certification thresholds. So, what's...
Article
Full-text available
In this paper we present the synthesis of the cam for a distribution mechanism used for Miller-Atkinson cycle and described in previous works. The input data contain the angles at which the valve opens and closes, respectively, the dimensions of the main parts, the maximum displacement of the valve. and the law of motion of the valve. The authors c...
Article
Full-text available
Increased environmental awareness and depletion of fossil petroleum resources are driving the automotive industry to seek out and use alternative fuels. For instance, the biofuel is a major renewable energy source to supplement declining fossil fuel resources. The addition of alcohols like methanol and ethanol is practical in biodiesel blends due t...
Article
Full-text available
The surge limit on automotive turbocharger needs to be avoided to prevent operations with pressure and mass flow oscillations. Mild surge is accompanied by noise which is disturbing. Deep surge can cause significant loss of engine power and severe drivability issues. It is necessary to know the stationary limit in order to match a turbocharger with...
Article
Full-text available
The mechanism considered in this paper is a VCR one consisting in a crank, a shaft, an intermediate triangular element and a control lever and it was described in previous papers of the authors. The authors start from a classical crank-shaft mechanism for which the extreme positions are known. The first stage of the synthesis consists in determinat...
Thesis
Full-text available
INTRODUCTION and EXTENDED ABSTRACT Road mobility is the engine of economic development and is one of the fundamental aspects of social cohesion because it allows everyone the freedom of movement, along with the advantages inherent to it: easy access to various jobs, to public services, vacations/leisure etc. Even though it still represents the mo...
Article
This article first gives a brief review of thermal engines designed for terrestrial transportation since the 1900s. We then outline the main developments in the state of the art and knowledge about internal combustion engines, focusing on the increasingly stringent pollution constraints imposed since the 1990s. The general concept of high-energy pe...
Conference Paper
The use of biodiesel fuel in compression ignition engines has the potential to reduce CO2, which can lead to a reduction in global warming and environmental hazards. Biodiesel is an attractive fuel, as it is made from renewable resources. A major drawback associated with the use of biodiesel, however, is its poor cold flow properties, which have a...
Conference Paper
Full-text available
Today, perhaps more than in the past, we think that the great question for the trinomial " academia-industry-state " is the following: are the graduate engineers " fit for purpose " and capable of operating in an industry that needs multi-and inter-disciplinary skills? In other words, is there a gap between industry needs for multi-skilled engineer...
Presentation
Full-text available
This is the presentation of the article published in The European Proceedings of Social & Behavioural Sciences further to the participation to Edu World 2016 Conference
Conference Paper
Full-text available
Technical inspection of a motor vehicle is an activity that should not be neglected and that is deemed to be binding both within the warranty period, but especially post - warranty. An engine malfunction may be due to unsuitable use of fuels and lubricants, resulting in a decrease in lubricating performances and protection of the oil. On the other...
Article
Full-text available
Increasing energy performance of internal combustion engines is largely influenced by frictional forces that arise between moving parts. Thus, in this respect, the nature and quality of the engine oil used is an important factor. Equally important is the effect of various engine injection strategies upon the oil quality. In other words, it's of utm...
Conference Paper
Full-text available
Fuel economy is a prime objective in order to meet regulatory and customer demands. Given this context, engine manufacturers are forced to introduce complex systems such as variable valve actuation (VVA). One of the simplest form of a VVA system is what is usually called as variable valve timing (VVT). What's important in these particular cases is...
Article
Full-text available
The use of biodiesel fuel in compression ignition engines has the potential to reduce CO2, which can lead to a reduction in global warming and environmental hazards. Biodiesel is an attractive fuel, as it is made from renewable resources. Many studies have been conducted to assess the impact of biodiesel use on engine performances. Most of them wer...