Chiheb Bouden

University of Tunis El Manar | FST · Department of Industrial Engineering

Parabolic Trough Collectors (PTCs) are the most mature, reliable and widespread among Concentrated Solar Power (CSP) technologies for electricity generation. The conventional power plants relying on PTCs use synthetic oil as Heat Transfer Fluid (HTF) which has limited life span, has limited operation temperature, is expensive and harmful to the env...

The COVID-19 pandemic has affected the economy of Tunisia, like that of many other countries. With electricity consumption dropping, consumption patterns changing, international fuel prices oscillating and uncertainty raging, the pandemic has affected not least the planning of investments in electricity supply. Although the government seems unlikel...

The COVID-19 pandemic has affected the economy of Tunisia, like that of many other countries. With electricity consumption dropping, consumption patterns changing, international fuel prices plummeting and uncertainty raging, the pandemic has affected not least the planning of investments in electricity supply. Although the government seems unlikely...

The COVID-19 pandemic has affected the economy of Tunisia, like that of many other countries. With electricity consumption dropping, consumption patterns changing, international fuel prices plummeting and uncertainty raging, the pandemic has affected not least the planning of investments in electricity supply. Although the government seems unlikely...

Energy systems modelling aims to introduce a sustainable energy system design with an improved understanding of present and future interactions between demand-supply, environment, and economy. Treating energy systems started in the 1950s and have led to various approaches and models. Amongst common metrics, the discount rate impacts time horizon co...

A renewable electricity system hybrid concentrated solar power/biomass power plant in Tunisia has been assessed. Life Cycle Assessment (LCA) and the Input-Output Analysis (IOA) methodologies have been performed to assess the environmental and socioeconomic impacts of this technology in the Tunisian context. Application of these methodologies allowe...

A renewable electricity system hybrid concentrated solar power/biomass power plantin Tunisia has been assessed. Life Cycle Assessment (LCA) and the Input-Output Analysis (IOA) methodologies have been performed to assess the environmental and socio-economic impacts of this technology in the Tunisian context. Application of these methodologies allowe...

Energy subsidy programmes are socio-economically designed to offer a modern and affordable energy, accessible for specific social groups, protect domestic industry, simulate economic development and protect the environment. However, in several countries, energy subsidies have deviated from their objectives and become an energy budget burden and a s...

Energy transitions in developing countries principally consist of the integration of renewable energies and energy efficiency in order to achieve a sustainability framework. Particularly, energy stakeholders are responsible for power planning to assure a country transition. Alongside, they are responsible for providing access to energy through syst...

Direct Steam Generation (DSG) has attracted considerable attention in comparison with conventional technologies based on Heat Transfer Fluids (HTF) for electricity generation due to its higher temperatures. In this context, a detailed numerical model has been developed, not only for comparison and assessment purposes but also for optimization analy...

The present work is elaborated in the framework of the REELCOOP research project. A mini hybrid (solar/biomass) power plant was installed and is under testing at ENIT (Ecole Nationale d’Ingénieurs de Tunis), Tunisia. The power plant relies on Parabolic Trough Collectors (PTC) operating with Direct Steam Generation (DSG), an Organic Rankine Cycle (O...

Recognizing the value of open-source research databases in advancing the art and science of HVAC, in 2014 the ASHRAE Global Thermal Comfort Database II project was launched under the leadership of University of California at Berkeley's Center for the Built Environment and The University of Sydney's Indoor Environmental Quality (IEQ) Laboratory. The...

The electricity mix in Tunisia mainly relied on conventional energy sources for over 50 years. Recently, due to fossil fuel prices oscillations and national reserves shortage, the need arose for restructuring the energy supply system. Targeting the integration of renewable energies could be a plan for satisfying the increasing demand and the supply...

The objective of this paper is to assess the impact of the inner layer composition in a double-skin façade system on the energy requirements of conditioned office buildings. Considering a typical office building in Tunis covered with a naturally ventilated box-façade, simulations are conducted for the hot and the cold seasons. The results show that...

In this paper, the development of a TRNSYS model, for the simulation of a solar driven ejector cooling system with an integrated PCM cold storage is presented. The simulations were carried out with the aim of satisfying the cooling needs of a 140 m3 space during the summer season in Tunis, Tunisia. The system is composed of three main subsystems, w...

Due to the economic development and occupancy requests, building thermal comfort reached higher levels during the last years. Energy consumption rates have become excessive and engendered an increasing reliance on fossil-fuel reserves. Hence, the conception of energy-efficient buildings as well as applying solar cooling techniques has become a prom...

A computational fluid dynamics (CFD) model was developed for the simulation of a phase change thermal energy storage process in a 100 l cylindrical tank, horizontally placed. The model is validated with experimental data obtained for the same configuration. The cold storage unit was charged using water as the heat transfer medium, flowing inside a...

The paper dealt in its first part with the assessment of the thermal behavior of an office building located in the Center of Researches and Energy Technologies. The second part focused on the evaluation of the performance of the solar absorption plant used for cooling. The simulations assessed the building in its existing structure and in its passi...

This paper presents a numerical study of a 5kW steam ejector using CFD with the objective of identifying the optimal operating conditions ensuring a high performance ejector cooling cycle. The flow structure and the mixing process inside the ejector were assessed for a range of operating conditions typical for a solar driven air conditioning system...

The numerical simulation, design, and construction of a double glazed integrated collector storage (ICS) with compound parabolic concentrators (CPC) reflectors are presented. The design of the double glazing is optimized by means of numerical simulations under Tunisian climatic conditions. The numerical program used for the simulation consists on t...

Aiming at developing a decision aid tool for double-skin façades (DSF) design in the Mediterranean climate, this study has coupled CONTAM with TRNSYS to evaluate the thermal/ventilation performance of the façade under dynamic climatic conditions. Similar coupling thermal building simulations to nodal airflow network simulations have been performed...

The REELCOOP project funded by the European Union aims at developing and demonstrating three small scale solar electricity generating units with two of them using thermal power cycles and one using PV. The system described here includes parabolic trough collectors and an organic Rankine cycle (ORC), enhanced by a biogas boiler and a thermal storage...

In this work a three dimensional heat transfer analysis of honeycomb Transparent Insulation Materials (TIM) destined for improving the efficiency of flat plate solar collectors is performed. The cellular and repetitive nature of the TIM structure has allowed simplify the problem and simulate a single isolated cell with opaque and adiabatic walls. T...

The aim of this work is to develop a numerical code able to predict the thermal behavior of a double tank integrated collector storage system (ICS) with compound parabolic concentrator (CPC). The developed numerical model is based on the detailed analysis of the different forms of heat transfers occurring in the ICS system. The balance equations of...

This paper presents a numerical study of a steam ejector using CFD with the objective of identifying suitable experimental conditions that allows for a reliable ejector cycle operation. The flow structure and the mixing process inside the ejector were assessed for a range of operating conditions typical for a solar driven air conditioning system. T...

The need for air-conditioning in the Mediterranean countries is higher and higher due to the effects of global warming. This paper deals with an investigation of a high performance, solar-driven air-conditioning system, the project entitled "Mediterranean AIRCOND", is funded by the European Community under the 'Community Activities in the Field of...

The cooling process by natural convection in cylindrical cavities is a phenomenon which takes place in several applications such as solar energy systems. In the present work a storage tank with an internal gas flue is studied experimentally and numerically during its long-term cooling process. The computational domain includes two fluids, i.e. wate...

Problem statement: Although that the interest attributed to the solar energy remains relatively limited, we attend today to the conception of several installations using the sun as energy source among which we quote the solar water heater. Approach: A study of energetic performances was taken on an integrated collector/storage solar water heater ma...

The transient cooling of a fluid initially at rest, inside a storage tank with an internal gas flue submitted to heat losses to the ambient is studied. In order to identify the relevant non-dimensional groups that define the transient natural convection phenomenom that occurs, a nondimensional analysis is carried out. A parametric study by means of...

Nous présentons dans cet article un modèle de machine frigorifique à absorption développé sous l’environnement EES (Engineering Equation Solver). Ce modèle nous permet d’étudier les différents phénomènes régissant le fonctionnement d’une machine frigorifique à absorption à simple effet fonctionnant avec le couple eau-ammoniac. Les simulations effec...

On étudie numériquement les échanges de chaleur ainsi que la stratification développés dans un ballon de stockage d'eau. Les équations qui régissent les écoulements et les transferts de chaleur à l'intérieur de l'accumulateur d'eau sont discrétisées par la méthode des volumes finis. Le maillage a été réalisé à l'aide du logiciel Gambit ; les calcul...

The glass curtain walls have been recently introduced in Tunisia; they are seen as a new fashion and are highly appreciated by some for their pleasing aesthetics. The objective of this paper is to investigate whether the glass curtain walls are appropriate for the Tunisian local climate and context and if it is so, to give recommendations concernin...

A thermal comfort field survey has been conducted in five towns from two climatic zones in Tunisia. Two hundred persons were concerned by this survey. They have been asked in their houses and working places at their normal living conditions once each month during 1 year.The selected sample of buildings has been chosen among free running buildings....

The rural regions of south Mediterranean countries suffer from problems of drinking water supply. However, the majority of these regions have important resources of brackish salt water. Thus, brackish water desalination on a small scale presents a potential solution to this problem. For this reason, a number of small desalination prototypes are bei...

Although Tunisian winters are mild compared with northern regions, there are heating requirements; their limited level suggests that passive solar energy would probably be able to meet them. However, the summer is hot enough, and one may wonder whether a solar design oriented toward the cold season would not induce severe overheating. Numerous stud...

In Tunisia, heating requirements in winter are not very high; solar radiation is abundant and offers a high potential of energy for heating. Passive conversion seems suitable due to the low associated extra costs. Moreover, the high thermal capacity required for solar buildings is usually present in single family houses. The National School for Eng...

The thermal inertia of building materials can be regarded as a temperature regulator in the traditional tunisian houses, however this method can not be usually used because of its cost. Simulations have been done with the “TRNSYS” program, to find the best value and disposition of the thermal inertia in the climate of Tunis.

Résumé -Connaître les performances et identifier les paramètres d'un chauffe eau solaire s'avère nécessaire pour améliorer sa qualité et par suite garantir à l'utilisateur le confort dont il est habitué avec les autres types d'énergies épuisables. Pour cette raison, on a besoin d'une méthode de test fiable et reproductible et au même temps peu coût...

Résumé -Au Laboratoire d'Energie Solaire de l'ENIT, nous effectuons depuis quelques années des tests pour les capteurs et les composants solaires. Actuellement, nous travaillons pour mettre au point une procédure de test pour l'ensemble du chauffe-eau solaire adaptée au contexte tunisien. A cet effet, nous avons commencé par tester une série de cha...