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Rosenberg J. Romero - One of the best experts on this subject based on the ideXlab platform.

  • Experimental assessment of double-absorption Heat Transformer operating with H2O/LiBr
    Applied Thermal Engineering, 2018
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, A. Huicochea, A. Lozano
    Abstract:

    Abstract This paper reports on the experimental results of a double-absorption Heat Transformer operating with a H2O/LiBr mixture. The generator and evaporator are pool boiling type Heat exchangers, while the remaining components are coils inside shells. Plots of gross temperature lifts, economizer efficiency, and internal and external performance coefficients are reported as functions of diverse operating parameters of the Heat Transformer. The results indicate that the system can achieve gross temperature lifts (GTLs) of between 48 °C and 74 °C, with internal performance coefficients varying from 0.12 to 0.37. The GTLs achieved are up to 30 °C higher than those reported in the literature, using a single-stage Heat Transformer operating with the same working mixture. Furthermore, the system exhibits effective stability and repeatability.

  • Predicted and experimental COP for Heat Transformer based on effectiveness process
    Experimental Thermal and Fluid Science, 2017
    Co-Authors: C.v. Valdez-morales, Rosenberg J. Romero, J. Ibarra-bahena
    Abstract:

    Abstract This paper proposes an accurate estimation for the experimental thermodynamic performance of a Single Stage Absorption Heat Transformer (SSHT). The calculation includes five Heat and mass transfer effectiveness factors of the components in the SSHT. The evaporator, condenser and Heat exchanger effectiveness is based on the method of Number of transfer units (NTU). Absorber and generator effectiveness are correlated with mass transfer, concentrations of the working mixture, and external powers, respectively. Calculations according to the operating conditions of the experimental tests were carried out in a 4 kW absorption Heat Transformer. The experiment was performed with the water/Carrol mixture with concentrations from 66 to 69%w; the actual Coefficient of Performance (COP a ) values were from 0.28 to 0.35, while the classical model overestimates these values from 0.47 to 0.49, respectively. The predicted COPη with these effectiveness factors is much more accurate (error factor lower than 92.25%) with COP a .

  • Environmental Impact Assessment for an Absorption Heat Transformer
    Open Journal of Applied Sciences, 2016
    Co-Authors: Jorge Avelino Domínguez Patiño, Rosenberg J. Romero, Antonio Rodríguez Martínez, J. Ibarra-bahena, Martha Lilia Domínguez Patiño
    Abstract:

    This study presents the environmental impact assessment of an absorption Heat Transformer designed to recover 1 kW of thermal energy from each 2 kW of waste Heat supplies. The net contribution of the Heat Transformer is a load avoided of 0.665 kg CO2 equivalents; the recovery process avoids 0.729 kg CO2 equivalents and the major contribution to the environment impacts is the pumping process with 0.0437 kg CO2 equivalents for each 1 kWh recovered. The study results show that absorption Heat Transformer is a good environmental option because it produces useful energy from waste Heat and the final result is an environmental impact diminution.

  • Comparison of Double Stage Heat Transformer with Double Absorption Heat Transformer Operating with Carrol – Water for Industrial Waste Heat Recovery
    Chemical engineering transactions, 2011
    Co-Authors: Rosenberg J. Romero, A. Rodríguez-martínez, J. Cerezo, Wilfrido Rivera
    Abstract:

    Double Absorption Heat Transformer Operating with Carrol – Water for Industrial Waste Heat Recovery Rosenberg J. Romero, Antonio Rodriguez Martinez, Sotsil Silva, Jesus Cerezo, W. Rivera Engineering and Applied Science Research Centre (CIICAP), Autonomous University of Morelos State. Av. Universidad 1001, Chamilpa (62209), Cuernavaca, Morelos, Mexico, rosenberg@uaem.mx Renewable Energy Studies Centre, Eng Inst (II), Autonomous Univ of Baja California Calle de la Normal s/n, Col. Insurgentes Este, (21280) Mexicali, B.C., Mexico Energy Research Centre (CIE), National Autonomous University of Mexico, Av. Xochicalco S/N, Centro (62580), Temixco, Morelos, Mexico

  • Double Stage Heat Transformer Controlled by Flow Ratio
    Innovations in Computing Sciences and Software Engineering, 2010
    Co-Authors: S. Silva-sotelo, Rosenberg J. Romero, A. Rodríguez – Martínez
    Abstract:

    this paper shows the values of Flow ratio (FR) for control of an absorption double stage Heat Transformer. The main parameters for the Heat pump system are defined as COP, FR and GTL. The control of the entire system is based in a new definition of FR. The Heat balance of the Double Stage Heat Transformer (DSHT) is used for the control. The mass flow is calculated for a HPVEE program and a second program control the mass flow. The mass flow is controlled by gear pumps connected to LabView program. The results show an increment in the fraction of the recovery energy. An example of oil distillation is used for the calculation. The waste Heat energy is added at the system at 70 °C. Water ™ - Carrol mixture is used in the DSHT. The recover energy is obtained in a second absorber at 128 °C with two scenarios.

Wilfrido Rivera - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of a Double Effect Heat Transformer Operating with Water/Lithium Bromide
    Processes, 2019
    Co-Authors: Itzel N. Balderas-sánchez, J. Camilo Jiménez-garcía, Wilfrido Rivera
    Abstract:

    Absorption Heat Transformers are effective systems for a wide variety of applications; however, their main purpose is to upgrade thermal energy from several sources at low-temperature up to a higher temperature level. In the literature, several advanced configurations for absorption Heat Transformers have been reported which are mainly focused on the improvement of the gross temperature lift by the use of a double absorption process; however, these systems usually offer a reduced coefficient of performance. The present study proposes a new advanced configuration of an absorption Heat Transformer that improves the coefficient of performance utilizing a double generation process. The operation of the new configuration was numerically modeled, and the main findings were discussed and presented emphasizing the effect of several parameters on the system performance. The highest coefficient of performance and gross temperature lift were 0.63 and 48 °C, respectively. From its comparison with a single-stage Heat Transformer, it is concluded that the proposed system may achieve coefficient of performance values up to 25.8% higher than those obtained with the single-stage system, although achieving lower gross temperature lifts.

  • Thermodynamic analysis of a novel absorption Heat Transformer
    Applied Thermal Engineering, 2019
    Co-Authors: Itzel N. Balderas-sánchez, Wilfrido Rivera, J. Camilo Jiménez-garcía
    Abstract:

    Abstract Heat Transformers are very useful for upgrading thermal energy to a higher temperature level. Up until now, several Heat Transformer configurations have been proposed and studied. In general, these configurations have been designed to enhance the coefficient of performance or the gross temperature lift. However, the systems that enhance the gross temperature lift significantly reduce the coefficient of performance. In the present study, we propose a novel double-stage-double-effect Heat Transformer that makes it possible to achieve a high gross temperature lift without a significant reduction in the coefficient of performance. The proposed system was modeled. The main results are graphically represented and discussed in this paper. Moreover, a comparison of the performance of several Heat Transformer configurations is presented. The new configuration achieved a gross temperature lift as high as 82 °C and a maximum coefficient of performance of 0.46. Compared to a single-stage Heat Transformer, it is shown that for specific conditions, the proposed system achieves similar coefficients of performance but with considerably higher gross temperature lifts. Compared to a double-stage Heat Transformer, it is shown that with the proposed system, the coefficients of performance are always considerably higher and similar or even higher gross temperature lifts can be achieved.

  • Experimental assessment of double-absorption Heat Transformer operating with H2O/LiBr
    Applied Thermal Engineering, 2018
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, A. Huicochea, A. Lozano
    Abstract:

    Abstract This paper reports on the experimental results of a double-absorption Heat Transformer operating with a H2O/LiBr mixture. The generator and evaporator are pool boiling type Heat exchangers, while the remaining components are coils inside shells. Plots of gross temperature lifts, economizer efficiency, and internal and external performance coefficients are reported as functions of diverse operating parameters of the Heat Transformer. The results indicate that the system can achieve gross temperature lifts (GTLs) of between 48 °C and 74 °C, with internal performance coefficients varying from 0.12 to 0.37. The GTLs achieved are up to 30 °C higher than those reported in the literature, using a single-stage Heat Transformer operating with the same working mixture. Furthermore, the system exhibits effective stability and repeatability.

  • Comparison of Double Stage Heat Transformer with Double Absorption Heat Transformer Operating with Carrol – Water for Industrial Waste Heat Recovery
    Chemical engineering transactions, 2011
    Co-Authors: Rosenberg J. Romero, A. Rodríguez-martínez, J. Cerezo, Wilfrido Rivera
    Abstract:

    Double Absorption Heat Transformer Operating with Carrol – Water for Industrial Waste Heat Recovery Rosenberg J. Romero, Antonio Rodriguez Martinez, Sotsil Silva, Jesus Cerezo, W. Rivera Engineering and Applied Science Research Centre (CIICAP), Autonomous University of Morelos State. Av. Universidad 1001, Chamilpa (62209), Cuernavaca, Morelos, Mexico, rosenberg@uaem.mx Renewable Energy Studies Centre, Eng Inst (II), Autonomous Univ of Baja California Calle de la Normal s/n, Col. Insurgentes Este, (21280) Mexicali, B.C., Mexico Energy Research Centre (CIE), National Autonomous University of Mexico, Av. Xochicalco S/N, Centro (62580), Temixco, Morelos, Mexico

  • Theoretical and experimental comparison of the performance of a single-stage Heat Transformer operating with water/lithium bromide and water/Carrol™
    International Journal of Energy Research, 2002
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, M.j. Cardoso, J. Aguillón, Roberto Best
    Abstract:

    This paper compares under the same operating conditions, the theoretical and experimental performance of a single-stage Heat Transformer operating with the water/lithium bromide and the water/Carrol™ mixtures, where Carrol™ is a mixture of lithium bromide and ethylene glycol [(CH2OH)2] in the ratio 1:4.5 by weight patented by Carrier Corp. Flow ratios, gross temperature lifts, useful Heat, and coefficients of performance are plotted for the Heat Transformer against temperatures and solution concentrations. Because the water/Carrol™ mixture has higher solubility than water/lithium bromide and high experimental values were obtained for the gross temperature lift, it seems to be a better alternative mixture to be used in absorption Heat Transformers. Copyright © 2002 John Wiley & Sons, Ltd.

J. Siqueiros - One of the best experts on this subject based on the ideXlab platform.

  • Energy saving into an absorption Heat Transformer by using Heat pipes between evaporator and condenser
    Applied Thermal Engineering, 2018
    Co-Authors: M.i. Heredia, José A. Hernández, J. Siqueiros, D. Juárez-romero, A. Huicochea, J.g. González-rodríguez
    Abstract:

    Abstract This study explores the feasibility of using Heat pipes as Heat exchangers inside an absorption Heat pump type II (Absorption Heat Transformer) of a thermal capacity of 0.7 kW. The Heat pipe is a passive device to transfer Heat because of low thermal resistance. A Heat exchanger with Heat pipes can be integrated between the condensation and evaporation processes of an Absorption Heat Transformer. This study has demonstrated that seven commercial Heat pipes are required to condense 0.714 kW and to reuse 0.177 kW at 60 °C in the evaporator, representing almost a third part of total Heat supplied without Heat pipes, provided that the generator temperature is over 55 °C. Therefore, the efficiency of the Absorption Heat Transformer can be improved based on the concept of the Coefficient of Performance up to 20%.

  • a novel cogeneration system a proton exchange membrane fuel cell coupled to a Heat Transformer
    Applied Thermal Engineering, 2013
    Co-Authors: A. Huicochea, J. Siqueiros, W Rivera, R J Romero, G Gutierrezurueta, I Pilatowsky
    Abstract:

    Abstract This study focuses on the potential of a novel cogeneration system which consists of a 5 kW proton exchange membrane fuel cell (PEMFC) and an absorption Heat Transformer (AHT). The dissipation Heat resulting from the operation of the PEMFC would be used to feed the absorption Heat Transformer, which is integrated to a water purification system. Therefore, the products of the proposed cogeneration system are Heat, electricity and distilled water. The study includes a simulation for the PEMFC as well as experimental results obtained with an experimental AHT facility. Based on the simulation results, experimental tests were performed in order to estimate the performance parameters of the overall system. This is possible due to the matching in power and temperatures between the outlet conditions of the simulated fuel cell and the inlet requirements of the AHT. Experimental coefficients of performance are reported for the AHT as well as the overall cogeneration efficiency for the integrated system. The results show that experimental values of coefficient of performance of the AHT and the overall cogeneration efficiency, can reach up to 0.256 and 0.571, respectively. This represents an increment in 12.4% of efficiency, compared to the fuel cell efficiency working individually. This study shows that the combined use of AHT systems with a PEMFC is possible and it is a very feasible project to be developed in the Centro de Investigacion en Energia (Centre of Energy Research), Mexico.

  • exergy analysis of an experimental Heat Transformer for water purification
    Energy, 2011
    Co-Authors: W Rivera, J. Siqueiros, A. Huicochea, H Martinez, D Juarez, Erasmo Cadenas
    Abstract:

    First and second law of thermodynamics have been used to analyze the performance of an experimental Heat Transformer used for water purification. The pure water is produced in the auxiliary condenser delivering an amount of Heat, which is recycled into the Heat Transformer increasing the Heat source temperatures and also the internal, external and exergy coefficients of performance. The theoretical and experimental study was divided into two parts. In the first part, a second law analysis was carried out to the experimental system showing that the absorber and the condenser are the components with the highest irreversibilities. In the second part, with the results obtained from the second law analysis, new test runs were carried out at similar conditions than the former but varying only one selected temperature at the time. Comparing the COP (coefficient of performance) between the old and new test runs, it was shown that higher internal, external and exergy coefficients of performance were obtained in all the new test runs. Also it was shown that the ECOP (exergy coefficient of performance) increases with an increment of the amount of the purified water produced and with the decrease of the flow ratio.

  • exergy analysis of a Heat Transformer for water purification increasing Heat source temperature
    Applied Thermal Engineering, 2010
    Co-Authors: W Rivera, J. Siqueiros, H Martinez, A. Huicochea
    Abstract:

    Abstract In the present study, the first and second laws of thermodynamic have been used to analyse in detail the performance of a Heat Transformer used for water purification. The Heat delivered in the auxiliary condenser is recycled into the system increasing the Heat source temperatures and therefore the coefficient of performance (COP) and the exergy coefficient of performance (ECOP). Plots of COP, ECOP, the improvement potential (IP) and the cycle irreversibility (ICYCLE) are shown against the main operating temperatures of the system, the gross temperature lift (GTL), the flow ratio (FR) and the effectiveness of the economiser (EFEC). In order to found the components of the system with the highest irreversibilities, plots of the irreversibilities for each one of the main components of the system are reported against the main temperatures and operating parameters of the Heat Transformer. The results showed that the highest irreversibilities occurred in the absorber contributing with more than the 30% of the irreversibilities of the entire system, followed by the auxiliary condenser with about the 25%. The lowest irreversibilities were found in the pumps which are almost negligible and in the economiser which were in general lower than 5%.

  • improved efficiency of energy use of a Heat Transformer using a water purification system
    Desalination, 2010
    Co-Authors: A. Huicochea, J. Siqueiros
    Abstract:

    Abstract One application of a Heat Transformer consists in obtaining purified water through single effect evaporation. A fraction of the obtained Heat in the absorber can be recycled to only one component of Heat source (either in the generator or in the evaporator) to improve efficiency of energy use of the equipment itself. This paper shows the results obtained with a thermodynamic simulator, using lithium bromide–water as working solution at different operation conditions in a 700 W experimental Heat Transformer. The behavior of Enthalpy Coefficient of Performance is presented as a function of the absorber temperature under different performance conditions in the generator and evaporator. The coefficients of performance are compared to various increases in the temperature of Heat source by applying Heat recycling to only one component and both components. Under the same performance conditions, when the Heat recycling is applied to the generator, the coefficient of performance results in a 110.3% increase, while applied to the evaporator, it results in a 61.5% increase and 79.3% when it is recycling in both components.

A. Huicochea - One of the best experts on this subject based on the ideXlab platform.

  • Experimental assessment of double-absorption Heat Transformer operating with H2O/LiBr
    Applied Thermal Engineering, 2018
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, A. Huicochea, A. Lozano
    Abstract:

    Abstract This paper reports on the experimental results of a double-absorption Heat Transformer operating with a H2O/LiBr mixture. The generator and evaporator are pool boiling type Heat exchangers, while the remaining components are coils inside shells. Plots of gross temperature lifts, economizer efficiency, and internal and external performance coefficients are reported as functions of diverse operating parameters of the Heat Transformer. The results indicate that the system can achieve gross temperature lifts (GTLs) of between 48 °C and 74 °C, with internal performance coefficients varying from 0.12 to 0.37. The GTLs achieved are up to 30 °C higher than those reported in the literature, using a single-stage Heat Transformer operating with the same working mixture. Furthermore, the system exhibits effective stability and repeatability.

  • Energy saving into an absorption Heat Transformer by using Heat pipes between evaporator and condenser
    Applied Thermal Engineering, 2018
    Co-Authors: M.i. Heredia, José A. Hernández, J. Siqueiros, D. Juárez-romero, A. Huicochea, J.g. González-rodríguez
    Abstract:

    Abstract This study explores the feasibility of using Heat pipes as Heat exchangers inside an absorption Heat pump type II (Absorption Heat Transformer) of a thermal capacity of 0.7 kW. The Heat pipe is a passive device to transfer Heat because of low thermal resistance. A Heat exchanger with Heat pipes can be integrated between the condensation and evaporation processes of an Absorption Heat Transformer. This study has demonstrated that seven commercial Heat pipes are required to condense 0.714 kW and to reuse 0.177 kW at 60 °C in the evaporator, representing almost a third part of total Heat supplied without Heat pipes, provided that the generator temperature is over 55 °C. Therefore, the efficiency of the Absorption Heat Transformer can be improved based on the concept of the Coefficient of Performance up to 20%.

  • a novel cogeneration system a proton exchange membrane fuel cell coupled to a Heat Transformer
    Applied Thermal Engineering, 2013
    Co-Authors: A. Huicochea, J. Siqueiros, W Rivera, R J Romero, G Gutierrezurueta, I Pilatowsky
    Abstract:

    Abstract This study focuses on the potential of a novel cogeneration system which consists of a 5 kW proton exchange membrane fuel cell (PEMFC) and an absorption Heat Transformer (AHT). The dissipation Heat resulting from the operation of the PEMFC would be used to feed the absorption Heat Transformer, which is integrated to a water purification system. Therefore, the products of the proposed cogeneration system are Heat, electricity and distilled water. The study includes a simulation for the PEMFC as well as experimental results obtained with an experimental AHT facility. Based on the simulation results, experimental tests were performed in order to estimate the performance parameters of the overall system. This is possible due to the matching in power and temperatures between the outlet conditions of the simulated fuel cell and the inlet requirements of the AHT. Experimental coefficients of performance are reported for the AHT as well as the overall cogeneration efficiency for the integrated system. The results show that experimental values of coefficient of performance of the AHT and the overall cogeneration efficiency, can reach up to 0.256 and 0.571, respectively. This represents an increment in 12.4% of efficiency, compared to the fuel cell efficiency working individually. This study shows that the combined use of AHT systems with a PEMFC is possible and it is a very feasible project to be developed in the Centro de Investigacion en Energia (Centre of Energy Research), Mexico.

  • exergy analysis of an experimental Heat Transformer for water purification
    Energy, 2011
    Co-Authors: W Rivera, J. Siqueiros, A. Huicochea, H Martinez, D Juarez, Erasmo Cadenas
    Abstract:

    First and second law of thermodynamics have been used to analyze the performance of an experimental Heat Transformer used for water purification. The pure water is produced in the auxiliary condenser delivering an amount of Heat, which is recycled into the Heat Transformer increasing the Heat source temperatures and also the internal, external and exergy coefficients of performance. The theoretical and experimental study was divided into two parts. In the first part, a second law analysis was carried out to the experimental system showing that the absorber and the condenser are the components with the highest irreversibilities. In the second part, with the results obtained from the second law analysis, new test runs were carried out at similar conditions than the former but varying only one selected temperature at the time. Comparing the COP (coefficient of performance) between the old and new test runs, it was shown that higher internal, external and exergy coefficients of performance were obtained in all the new test runs. Also it was shown that the ECOP (exergy coefficient of performance) increases with an increment of the amount of the purified water produced and with the decrease of the flow ratio.

  • exergy analysis of a Heat Transformer for water purification increasing Heat source temperature
    Applied Thermal Engineering, 2010
    Co-Authors: W Rivera, J. Siqueiros, H Martinez, A. Huicochea
    Abstract:

    Abstract In the present study, the first and second laws of thermodynamic have been used to analyse in detail the performance of a Heat Transformer used for water purification. The Heat delivered in the auxiliary condenser is recycled into the system increasing the Heat source temperatures and therefore the coefficient of performance (COP) and the exergy coefficient of performance (ECOP). Plots of COP, ECOP, the improvement potential (IP) and the cycle irreversibility (ICYCLE) are shown against the main operating temperatures of the system, the gross temperature lift (GTL), the flow ratio (FR) and the effectiveness of the economiser (EFEC). In order to found the components of the system with the highest irreversibilities, plots of the irreversibilities for each one of the main components of the system are reported against the main temperatures and operating parameters of the Heat Transformer. The results showed that the highest irreversibilities occurred in the absorber contributing with more than the 30% of the irreversibilities of the entire system, followed by the auxiliary condenser with about the 25%. The lowest irreversibilities were found in the pumps which are almost negligible and in the economiser which were in general lower than 5%.

Roberto Best - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical and experimental comparison of the performance of a single-stage Heat Transformer operating with water/lithium bromide and water/Carrol™
    International Journal of Energy Research, 2002
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, M.j. Cardoso, J. Aguillón, Roberto Best
    Abstract:

    This paper compares under the same operating conditions, the theoretical and experimental performance of a single-stage Heat Transformer operating with the water/lithium bromide and the water/Carrol™ mixtures, where Carrol™ is a mixture of lithium bromide and ethylene glycol [(CH2OH)2] in the ratio 1:4.5 by weight patented by Carrier Corp. Flow ratios, gross temperature lifts, useful Heat, and coefficients of performance are plotted for the Heat Transformer against temperatures and solution concentrations. Because the water/Carrol™ mixture has higher solubility than water/lithium bromide and high experimental values were obtained for the gross temperature lift, it seems to be a better alternative mixture to be used in absorption Heat Transformers. Copyright © 2002 John Wiley & Sons, Ltd.

  • Experimental evaluation of a single-stage Heat Transformer operating with the water/Carrol™ mixture
    Energy, 1999
    Co-Authors: Wilfrido Rivera, Rosenberg J. Romero, Roberto Best, C.l. Heard
    Abstract:

    Abstract This paper describes experimental results obtained with a single-stage Heat Transformer (SSHT). Many combinations of fluid pairs have been proposed although only the water/lithium bromide mixture has been widely used. The experimental work was done using the water/Carrol™ mixture, where Carrol™ is a mixture of LiBr and ethylene glycol [(CH2OH)2] in the ratio 1:4.5 by weight. Flow ratios, gross temperature lifts, useful Heat, and coefficients of performance are plotted for the Heat Transformer vs temperatures and solution concentrations. Because the water/Carrol™ mixture has higher solubility than water/lithium bromide and high experimental values are obtained for the gross temperature lift, it is a preferred mixture.

  • Experimental performance of ternary solutions in an absorption Heat Transformer
    International Journal of Energy Research, 1998
    Co-Authors: R. M. Barragán, C.l. Heard, V. M. Arellano, Roberto Best
    Abstract:

    In this work, results from experiments with ternary solutions in an absorption Heat Transformer are presented. The experiments were performed under controlled conditions using water/lithium chloride/zinc chloride and water/calcium chloride/zinc chloride solutions as working pairs. The results showed that the gross temperature lift is increased with regard to the results obtained using binary solutions because the concentration of the solutions was enhanced. The water/lithium chloride/zinc chloride solution showed a generally better performance than the water/calcium chloride/zinc chloride mixture. The highest gross temperature lift for the former solution was 37.5°C for an absorber temperature of 96°C. This result compared favourably to that previously obtained for water/lithium bromide in the University of Salford.