Series Of Heat Exchangers Research Articles

Fuzzy Control Design for Energy Efficient Heat Exchanger Network

Increasing energy efficiency and decreasing power consumption play a substantial role in the modern industrial and technological world. Consequently, there are enhanced requirements on all production processes and especially on energy intensive processes. Heat exchangers (HEs) and heat exchanger networks (HENs) are very energy intensive processes and only their optimal operation assures efficient heat recovery. Advanced optimization and advanced control are tools for assuring the energetic efficacy of HEs or HENs. Between them, fuzzy logic control represents the advanced control strategy that has many applications in industry and advantages as it can be used for control of strongly non-linear processes and processes that are difficult to control because of asymmetric dynamics or uncertainties. The type-1 and type-2 fuzzy logic controllers (FLCs) designed for a small heat exchanger network (HEN) are compared in this paper using simulation results with the PI and PID controllers tuned by conventional methods. The controlled HEN was a combination of two heat exchangers in series and one in parallel to them. The best controller was the type-2 fuzzy logic controller (FLC). This controller assured the most efficient operation of HEN measured by the smallest coolant consumption. The coolant consumption increased exploiting the type-1 FLC by 2 %, the PI controller by 3 %, and the PID controller by 5 %.

Characterizing SOFC Stack Electrochemical Performance at Elevated Pressure

In this report, we present our work to characterize the electrochemical performance of solid-oxide fuel cell stacks under elevated-pressure operation. The effort is part of a five-year U.S. DoE ARPA-E INTEGRATE program to combine the high efficiency of solid-oxide fuel cells with the low-cost of reciprocating engines to demonstrate an 70%-efficient hybrid electric generator. Within this hybrid system, solid-oxide fuel cells (SOFCs) convert natural gas into electricity. Unconverted fuel leaving the SOFC stacks feeds a downstream reciprocating engine that drives an electric generator. In this architecture, the stacks are hydraulically placed upstream of the engine, necessitating stack operation at elevated pressures of 2-5 barg. SOFC stack performance at elevated pressure has witnessed limited study. The team at the Colorado School of Mines is characterizing SOFC stack performance at elevated pressure through design and commissioning of the pressurized stack electrochemical test stand shown in the figure. The facility is used to explore the performance of 5-kW SOFC stack test modules (Ceres Power, Ltd., Horsham, UK) at the unusual operating conditions presented by the hybrid system, including pressurized operation at high anode tail-gas recycle.A simulant of steam-reformed natural gas with anode tail-gas recycle is synthesized using mass flow controllers. A fuel processor will be incorporated into the stand at a later stage of the research program. Reactants flow through a preheat furnace and into a pressure vessel to reach the insulated solid-oxide fuel cell stack test module. The pressure within this vessel is matched to the operating pressure of the SOFC stack, minimizing pressure differentials between the internal flow channels of the stack and the surrounding environment. Following electrochemical conversion, exhaust gases exit the stack and the pressure vessel, and are cooled through a series of heat exchangers. Back-pressure regulators near the end of the flow stream regulate stack and vessel operating pressure.The stand has been used to explore the impacts of elevated pressure operation on the electrochemical performance of Ceres SteelCell stacks. Additional parameters being explored include fuel composition, anode recycle, and internal fuel reforming. In this talk, we will present our findings on the effects of these variables on stack performance, and their impact in achieving the aggressive performance targets of the SOFC-engine hybrid electric generator.A principal concern during performance testing at elevated pressures is minimizing pressure differentials across the anode and cathode gas-flow streams. Such differentials can bring substantial mechanical stress to the metal-supported membrane-electrode assemblies. Pressure differentials in this work are below +/- 25 mbar at 5 barg operating pressure, well below manufacturer’s specifications. The stacks show steady, stable performance over all conditions tested.In addition to exploring the electrochemical-performance impacts brought by pressurization and anode recycle, experiments explore the roles of methane internal reforming and cathode air flow on stack cooling. The endothermicity of methane steam reforming can bring meaningful reductions in cooling-air flow rate, raising system efficiency. The results of these studies and the trajectory of the research will be presented. Figure 1

The New Generation of High-Pressure Heaters for Steam Turbine Units at Nuclear Power Plants

The designs of vertical high-pressure heaters (HPHs) for a regeneration system of steam-turbine units (STUs) at nuclear power plants are compared. The proposed heat exchanger with a header-platen tube system is compared with a conventional counterpart by thermohydraulic and design characteristics, weight and dimensions, and performance indicators. Excellent thermohydraulic performance of the proposed apparatus are brought about by the effective condensation due to a high velocity of the condensing steam flow in the shell’s side. The tube bundle consists of standardized platens, the spacing between which can vary in a wide range. The introduction of a cylindrical tube header in place of the tube sheet considerably decreases the wall thickness with a corresponding reduction in the apparatus weight and also prolongs the service life due to elimination of sludge build-up at tube-to-tube header attachment points. Easy maintenance of these heaters is enabled by the access to tubes fixed in the upper and lower vertical cylindrical tube headers through manholes to ergonomically plug faulty tubes. The manufacturing time of the apparatus exchanger and the man-hours for its installation decrease due to the application of standardized tube platens and a shorter length of tube attachment holes. The proposed design has been used as the basis for developing a series of heat exchangers for installation at operating and newly designed power units of NPPs. These apparatuses can accommodate two series-connected, two parallel-connected, or two-series-connected and two parallel-connected HPHs in a single shell, thereby reducing the footprint occupied in a turbine hall. The above-mentioned features of the developed apparatuses are important in the reconstruction (or modernization) of operating NPP power units when the steam capacity of a nuclear steam generating plant is to be increased. The introduction of the proposed apparatuses opens the new way to the optimization of the design, process, and space-and-layout solutions for the regeneration systems of existing and newly designed steam turbine units with a corresponding reduction in operating costs and capital investments in the construction or reconstruction of NPP power units.

Evaluation and Improvement of Thermal Energy of Heat Exchangers with SWCNT, GQD Nanoparticles and PCM (RT82)

Today, due to the reduction of energy resources in the world and its pollutants, energy storage methods and increase the thermal efficiency of various systems are very important. In this research, the thermal efficiency and energy storage of two heat exchangers have been investigated in series using phase change materials (RT82) and single wall carbon nanotubes (SWCNT) and graphene quantum dot nanoparticles (GQD) In this research, two heat exchangers have been used in combination. The first heat exchanger was in charge of storing thermal energy and the second heat exchanger was in charge of heat exchange. The reason for this is to improve the heat exchange of the main exchanger (shell and tube) by using heat storage in the secondary exchanger, which has not been addressed in previous research. The results of this study showed that using two heat exchangers in series, the thermal efficiency of the system has increased. Also, the heat energy storage of the double tube heat exchanger was obtained using phase change materials in the single-walled carbon nanotube composition of about 3000 W. The average thermal efficiency of the two heat exchangers as the series has increased by 52%. In general, the effect of the two heat exchangers on each other was investigated in series with two approaches (energy storage and energy conversion) using fin and nanoparticles, which obtained convincing results.

Characterizing SOFC Stack Electrochemical Performance at Elevated Pressure

In this report, we present our work to characterize the electrochemical performance of solid-oxide fuel cell stacks under elevated-pressure operation. The effort is part of a five-year U.S. DoE ARPA-E INTEGRATE program to combine the high efficiency of solid-oxide fuel cells with the low-cost of reciprocating engines to demonstrate an advanced hybrid electric generator. Within this hybrid system, solid-oxide fuel cells (SOFCs) convert natural gas into electricity. Unconverted fuel leaving the SOFC stacks feeds a downstream natural-gas reciprocating engine that drives an electric generator. In this architecture, the stacks are hydraulically placed upstream of the engine, necessitating stack operation at elevated pressures of 2-5 barg. SOFC stack performance at elevated pressure has witnessed limited study. The team at the Colorado School of Mines is characterizing SOFC stack performance at elevated pressure through design and commissioning of the pressurized stack electrochemical test stand shown in the figure.Reactive gases are regulated using mass flow controllers to simulate the reformate stream produced by a natural gas fuel processor. Such a fuel processor will be incorporated into the stand at a later stage of the research program. Reactants flow through a preheat furnace and into a pressure vessel to reach the solid-oxide fuel cell stack. The pressure within this vessel is matched to the operating pressure of the SOFC stack, minimizing pressure differentials between the internal flow channels of the stack and the surrounding environment. Following electrochemical conversion, exhaust gases exit the stack and the pressure vessel, and are cooled through a series of heat exchangers. Back-pressure regulators near the end of the flow stream regulate stack and vessel operating pressure.The stand has been used to explore the impacts of elevated pressure operation on the electrochemical performance and degradation of Ceres SteelCell stacks. Additional parameters being explored include the effects of fuel composition, anode recycle, and internal fuel reforming. In this talk, we will present preliminary findings on the effects of these variables on stack performance, and their impact in achieving the aggressive performance targets of the SOFC-engine hybrid electric generator. Figure 1

Operational strategies and pumping energy saving potential of the combined district heating system with peak-shaving gas-fired boilers in heating substations

Combined district heating (DH) systems have at least one base load heat plant and several peak-shaving heat sources, which can be installed in the primary network or in the heating substations. This article studies the combined DH system with peak-shaving gas-fired boilers in heating substations, where the peak boilers can be connected to the heat exchangers in series or parallel mode. We analyze the thermal balances for these two connection modes and obtain the analytical operational regulation formulas for them. Then we study the operational methods for each connection mode, considering the heat distribution control strategies in both primary and secondary networks. Adopted control strategies are (1) variable temperature (VT) control, (2) variable flowrate (VF) control, and (3) variable temperature and flowrate (VT-VF) control. The combinations of these three strategies in primary and secondary networks are compared in terms of pumping energy consumption. The results indicate that operational strategies should be phased into different periods according to whether the peak heating is needed or not. In addition, the pumping energy consumption for the parallel connection mode is less than that that for the series connection mode with the same operational strategy, and the VF control strategy shows better energy saving potential.

Control of heat exchangers in series using neural network predictive controllers

Abstract The paper reveals three applications of neural network predictive control (NNPC) to a system of four heat exchangers (HEs) in series with counterflow configuration to save energy expressed by cooling water in the system of HEs cooling the distillation product. Neural networks (NNs) are used at first in conventional NNPC and subsequently, neural network predictive controllers (NNPCLs) are employed as a master controller in a cascade control, and as a feedback controller in the control system with disturbance measurement. Neural-network-predictive-control-based (NNPC-based) feedback control systems are compared with PI controller based feedback control loop. Series of simulation experiments were done and the results showed that using NNPC-based cascade control reduced cooling water consumption. This control system also significantly reduced the settling time and overshoots in the control responses and provided the best assessed integral quality criteria compared to other control systems. NNPC-based cascade control can also be interesting for industrial use. Generally, simulation results proved that NNPC-based control systems are promising means for the improvement of HEs control and achievement of energy saving.

Minimization of entropy generation of a closed Brayton cycle based precooling-compression system for advanced hypersonic airbreathing engine

Fuel indirect precooled engines have the potential to radically reform the paradigm of propulsion for next generation in- and trans-atmospheric vehicles. The engine is characterized by a sophisticated thermodynamic cycle with a series of heat exchangers. Reducing irreversibility of the precooling-compression system (PCS) is the key to ensure high engine performance, for which a conjugated optimization coupled with heat exchanger design was performed to evaluate the performance level that can be achieved under the state of technologies. The results indicate that irreversibility of the PCS can be reduced but at the penalty of heavier and larger size of heat exchangers. Moreover, it shows that precooler and regenerator together contributes 75–84% of the total entropy generation rate within the PCS, while hydrogen pump occupies the second largest irreversibility source. Smaller precooling temperature can help to improve the extent of irreversibility of the PCS and increase the maximum achievable air pressure ratio and engine specific thrust, nevertheless the increased fuel consumption and air side pressure drop and the decreased engine specific impulse shouldn’t be ignored. Larger regenerator effectiveness is preferred from all aspects of the PCS and engine level figures of merit as long as the total weight and length of the heat exchangers are not increased aggressively.

SIMULATION STUDY OF PARABOLIC TROUGH SOLAR POWER PLANTS IN BRAZIL

Various data reveals the potential of concentrated solar technologies for the electricity production. With global growing energy demand and green-house gas emission, concentrating solar power is considered as one of the promising options and has invited wide attention. In this work, a model for a 30 MW parabolic trough solar power plant system was developed for 31 different locations in Brazil, using TRNSYS simulation software, and TESS and STEC libraries. The power system consists of a parabolic trough solar collector loop connected to a power block by a series of heat exchangers. The solar collector loop consists of a field of parabolic trough collectors, stratified thermal storage tank, pump and heat exchangers to drive the power block and uses Therminol VP1 as heat transfer fluid. The results show that the cities of Recife (PE), Fortaleza (CE), Belterra (PA), Salvador (BA) and Petrolina (PE) stand out for their high monthly values of direct normal irradiation and, resulting the highest production of energy by the same configuration of Solar Central Power Plant.

Some safety aspects on the cleavage of cumene hydroperoxide in the phenol process

The acid‐catalyzed cleavage of cumene hydroperoxide (CHP) to phenol and acetone is an exothermic reaction in homogeneous liquid phase. The reaction occurs within a minute. Therefore, a reliable heat removal and temperature control is essential in commercial units. In addition, an uncomplete conversion of CHP must be detectable to avoid any accumulation of the peroxide in the reaction system which can cause dangerous conditions. This article describes some process safety aspects of the CHP cleavage unit.The first part of the cleavage is a circulation loop with one or several heat exchangers in series to remove the heat from the exothermic reaction at around 50°C. CHP is added to the circulation loop and so diluted with cleavage product. The cleavage product consists of mainly phenol, acetone and cumene. Sulfuric acid in low concentrations is used as catalyst. CHP decomposes to phenol and acetone while passing through the cooler(s). In a specific side reaction, dicumylperoxide (DCP) is formed from CHP. Potential hazards in this unit rise from feeding too much CHP into the loop, which could lead to high temperatures and an impermissible high pressure due to the fast exothermic reaction. A failure of the equipment with product release could be the consequence. A countermeasure is for example a ratio control between the flows of the circulating cleavage product and the CHP feed stream. Another hazard for the circulation loop is the accumulation of CHP due to a deactivation of the sulfuric acid. A delayed start of the reaction could then lead to a severe runaway reaction when the accumulated CHP starts to decompose. This can cause a complete destruction of the unit. A “low temperature” interlock can be used to early stop the CHP feed in case of an acid deactivation.After this first cleavage unit, the product from the circulation loop is then treated in a second unit with a plug‐flow reactor operating at temperatures above 100°C. The temperature can be increased by adding CHP to use the exothermic reaction from decomposed CHP for heating‐up. In the downstream section of this second reactor, DCP reacts back to CHP at the higher temperature and this CHP immediately further decomposes to phenol and acetone. As well as for the circulation loop, too high concentrations of CHP can be avoided by a proper ratio‐controlled dosing of the CHP. A non‐complete conversion of CHP due to a loss of acid activity will result in a decrease of the temperature. This can be detected by either “low temperature” interlocks or, preferably, by permanently monitoring and verifying the “swan‐neck” temperature profile across the plug‐flow reactor. Finally, a sufficiently high conversion of DCP can be observed by the slope of the temperature profile at the end of the plug‐flow reactor. © 2019 American Institute of Chemical Engineers Process Saf Prog: e12034 2019

Experimental Performance Analysis of Shallow Spiral-tube Ground Heat Exchangers in Series and Parallel Configurations

Ground source cooling system (GSCS) uses a ground heat exchanger (GHE) for exchanging heat with the ground. A spiral-tube GHE is gaining interest in recent year. This study presents an experimental analysis of thermal performance of shallow spiral-tube ground heat exchanger (GHE) installed in the ground at 3 m depth in series and parallel configurations. These GHE configurations offer a compromise between the conventional vertical and horizontal GHEs. The spiral-tube GHE which is consist of spiral pipe installed in the borehole provides a better performance in application of GSCS. The thermal performances ofspiraltube GHE in series and parallel configurations were investigated under actual condition. Inlet and outlet temperatures of the both configurations were measured and periodically recorded. The average heat exchange rates of the GHEs are 122.4 W m –1 in parallel configuration and 86.2 W m –1in series configuration. Heat exchange rate of the spiral-tube GHEs in parallel configuration provides a better performance than that of in series configuration. The spiral-tube GHE in shallow depth can be applied in the GSCS.

Desarrollo de una red de tuberías de agua utilizada como sistema de enfriamiento por conducción aplicado a granjas lecheras

Introduction: In desert climates, high temperatures can cause heat stress on dairy farms. Aviable alternative to this problem is to develop a network of water pipes connected to heat exchangers (HEs) that operate as a conductive cooling system. Objective: To propose a water supply system connected to a series of HEs, installed under bedding in a dairy barn freestall system, and analyze heat transfer along a large-scale water pipe network. Methodology: The EPANET water quality module was used to design the system. Temperature predictions were validated with experimental data from a network of four HE pipes installed under the bedding. A network was then designed to supply water to 1 000 HEs in order tocalculate the efficiency of the system for a real dairy farm. Results: Insulations with values of 0.095 and 0.0475 W∙m-1∙°C-1 increased the cooling capacity of water-carrying pipes by 7 and 12 %, respectively. Increasing the flow rates from 1 to 7 L∙min-1 increased the cooling capacity; however, the cooling efficiency decreased by at least 12 %. Study limitations: A validation was performed on a section of the pipe network and a simulation for the entire network. Originality:V EPANET was implemented for a mass and heat balance in a pipe network supplying water to HEs. Conclusion: The conductive cooling system is viable in areas with a desert climate and its efficiency depends on the level of thermal insulation and flow in the pipe network.

A novel method for combined entropy generation and economic optimization of counter-current and co-current heat exchangers

In this paperwork, a novel methodology of entropy generation minimization (EGM) for counter-current and co-current heat exchangers is developed. The methodology can be applied in general case for all types of the heat exchangers with the counter-current and co-current flow configuration. A number of entropy generation units (NEGU) function, along with its pressure drop and temperature difference components, are presented. Additionally, evaluated EGM can be easily incorporated into some optimization algorithms for industrial practice. Beside of the theoretical background, on an example and case study were proved that the EGM analysis could be useful in practical applications of heat exchanger optimization. Furthermore, the correlation between the minimum value of NEGU and minimum of total annual costs (operational and investment costs) have been shown. Based on the EGM methodology, on a case study was presented that pressure drop of the plate counter-current heat exchangers in series should be 36 kPa, in order to achieve minimal annual costs of the 456 EUR/year. The result corresponds to the heat exchangers in series with 2 sections and 46 plates per section.

Investigation of a gas-fuelled water heater based on combined power and heat pump cycles

In this paper, we propose a novel gas-fuelled hot water system based on combined power and heat pump cycles. The proposed system essentially integrates a premixed gas burner, an organic Rankine cycle (ORC) power plant, and an air source heat pump for supplying hot water. An ORC power plant generates mechanical power from the thermal energy produced from the combustion of natural gas in the burner. Subsequently, the generated power directly drives a vapour compression cycle heat pump. Cold tap water is heated by three heat exchangers in series to gradually increase its temperature. It is preheated in the condenser of the heat pump, then heated in the condenser of the ORC power plant, and finally further heated by the flue gas exiting from the burner in a post heater. The flue gas exiting the post heater will be mixed with ambient air to further extract its residual heat in the evaporator of the heat pump. A comprehensive numerical analysis has been presented in this paper, and the results show that the proposed system can achieve an overall fuel-to-heat efficiency up to 147% when the cold water is heated from 10 to 65 °C and the ambient air temperature is in the range of −5 to 5 °C. The research results demonstrated that the proposed technology has a great potential for domestic hot water applications.

A Comparison of Utility Heat Exchanger Network Synthesis for Total Site Heat Integration Methods

This paper compares Utility Heat Exchanger Network (UEN) design between two Total Site Heat Integration (TSHI) methods, the Conventional Total Site Targeting method (CTST) and the recently developed Unified Total Site Targeting (UTST) method. A large Kraft Pulp Mill plant has been chosen as a case study. Total Site targets have been calculated using a ExcelTM targeting spreadsheet and networks have been designed with the help of SupertagetTM for both the CTST and UTST methods. To achieve heat recovery and utility targets, both series and parallel utility heat exchanger matches for non-isothermal utilities are allowed in the CTST method, while series matches are allowed in the UTST method if the heat exchangers in series are from the same process. Series matches based on CTST method may create a dependency on two or more separate processes, which operational and control issues may occur, higher piping costs may be imposed, and utility target temperatures may not be achieved in the consecutive processes if one or more processes were to be out of service. Relaxation of the network can resolve these issues for the CTST method; however, if the relaxation occurs on the side of the utility loop that constrains heat recovery, the net heat recovery targets may not be achieved within the Total Site. The UTST method with its modified targeting procedure may offer slightly lower heat recovery targets but with simpler UEN design compared to CTST method are more realistic and achievable. Finally, after UEN design, non-isothermal utility loops need to be balanced in terms of mass and energy for both methods.

Inverse problem and variation method to optimize cascade heat exchange network in central heating system

Urban heating in northern China accounts for 40% of total building energy usage. In central heating systems, heat is often transferred from heat source to users by the heat network where several heat exchangers are installed at heat source, substations and terminals respectively. For given overall heating capacity and heat source temperature, increasing the terminal fluid temperature is an effective way to improve the thermal performance of such cascade heat exchange network for energy saving. In this paper, the mathematical optimization model of the cascade heat exchange network with three-stage heat exchangers in series is established. Aim at maximizing the cold fluid temperature for given hot fluid temperature and overall heating capacity, the optimal heat exchange area distribution and the medium fluids’ flow rates are determined through inverse problem and variation method. The preliminary results show that the heat exchange areas should be distributed equally for each heat exchanger. It also indicates that in order to improve the thermal performance of the whole system, more heat exchange areas should be allocated to the heat exchanger where flow rate difference between two fluids is relatively small. This work is important for guiding the optimization design of practical cascade heating systems.

Study on the performance of an open-loop passive containment cooling system

ABSTRACT The containment is an ultimate and important barrier to keep the radioactivity from release. The integrity of the containment is crucial to control the consequences of either loss of coolant accident or main steam line break accident. A passive containment cooling system concept designed to remove the heat by natural circulation means is proposed, which is composed of a series of heat exchangers, long connecting pipes with relative large diameter, valves, and a water tank. The performance of the system is numerically simulated and the self-developed codes are validated by the experimental data. The influences of several key parameters are investigated on the performance of the system from different aspects. The results confirm that four distinct operating stages could be experienced as follows: startup stage, single-phase quasi-steady stage, flashing speed up transient stage, and flashing dominated quasi-steady operating stage. Furthermore, the mechanisms of the ways through which the parameters influence the behaviors of the proposed system are thus analyzed. Moreover, the feasibility of the system is also commented on the basis of the numerical results.

Cost-based design optimization of the heat exchangers in a parabolic trough power plant

This paper addresses two important concerns of the design of steam generators of parabolic trough power plants: cost minimization and component reliability. A thorough economic analysis of the heat exchangers of the steam generator and oil-to-salt heat exchangers of a 50 MWe parabolic trough power plant is presented. The heat exchanger design is realized following TEMA standards and optimized using a genetic algorithm. Two design strategies are compared: the minimization of the total heat transfer area and the minimization of the total annualized cost. It is seen that the second approach provides substantial savings over the lifetime of the plant.The economic analysis reveals a global optimum with an outlet temperature of the heat transfer fluid of 293 °C and an evaporator pinch point of 4.85 °C. The best design of the steam generator consists of a TEMA-H shell superheater and preheater and a TEMA-F shell reheater. The best design of the oil-to-salt heat exchangers includes six TEMA-F shell heat exchangers in series, with a log mean temperature difference of 7 °C and the molten salt on the shell-side. Lastly, a TEMA-X recirculation evaporator is proposed with a considerably reduced wall thickness when compared to a kettle evaporator.

Robust Model Predictive Control of Heat Exchangers in Series

This study investigates using of robust model based predictive control (MPC) algorithms for optimal operating of heat exchangers in series from the stability and economic viewpoints. For the advanced controller design, the influence of uncertain parameters was taken into account. In order to design the robust MPC, the optimization problem with constraints was formulated in the form of linear matrix inequalities and then the convex optimization problem was solved using the semidefinite programming. The designed robust MPC strategies were based on the worst-case optimization and on the additional control input saturation. We investigated a case study with two various significant disturbances in the temperature of the input stream in the heat exchangers in series. Results revealed that the robust MPC improved control performance and ensured energy savings during the heat exchanger network operation.

Determination of the Global Heat Transfer Coefficient of a Double Heat Exchanger Battery in a Dry Mode.

The cold battery is a heat exchanger between two fluids, air (secondary fluid) and iced water (primary fluid). The cold battery is composed of two heat exchangers in series, one of which is made up of flat-plate in galvanized steel serving as a reservoir for the iced water and the other one a copper shell and-tube exchanger with aluminum cooling blades. The two heat exchangers a connected pipe of the same diameter. These pipes will permit the transit of the iced water coming from the flat-plate exchanger by gravitation towards the tubes of the second exchanger. These two heat exchangers are incorporated in a galvanized container coupled with a centrifugal fan for the improvement of the thermal comfort. The water, after passing through the two heat exchangers is stored in an adiabatic reservoir and will serve as a water fountain [1]. The modeling will be done in a humid mode that is the temperature of the surface of the battery is very low compared with the dew temperature of air. The cooling allows the condensation of water vapor [2]. The characterization of that cold battery will be done in a dry regime where there is only one heat exchanger and the quantity of vapor contained in the air does not vary and also the surface temperature of the battery is greater than the dew temperature of air [2; 3].