This article reports on an experimental analysis and performance assessment of using thermoelectr... more This article reports on an experimental analysis and performance assessment of using thermoelectric generators (TEGs) for waste heat recovery from residential vapor compression refrigeration systems. The analysis shows that there is a good opportunity for waste heat recovery using TEGs by de-superheating refrigerant after the compressor. Design and manufacturing of a de-superheater unit consisting of a tube and plate heat exchanger and thermoelectric generator modules (HE-TEGs) have been performed and integrated in an experimental test rig of R134a refrigeration cycle. Experimental assessment of the performance parameters, as compared to the basic refrigeration system, reveals that the overall coefficient of performance (COP) using HE-TEGs desuperheater unit increases by values ranging from 17% to 32% depending on the condenser and evaporator loads. Exergy analysis shows that the enhancement is attributed to reduction in the exergy destruction in the condenser and compressor due to ...
Comparison between experiment and predicted junction temperatures vs. input current for (a) cold ... more Comparison between experiment and predicted junction temperatures vs. input current for (a) cold junction temperature and (b) hot junction temperature [37] ..... 6.12. Comparison between experiment and predicted cop and cold air temperature difference vs.
International Journal of Low-Carbon Technologies, 2021
The present article reports on the design, modeling and parametric optimization of a thermoelectr... more The present article reports on the design, modeling and parametric optimization of a thermoelectric cooling system for electronics applications. An analytical model based on energy equilibrium is developed for cooling a microprocessor using a thermoelectric module with an air-cooled finned heat sink. The proposed analytical model is validated by experimental measurements and by comparison with detailed 3D numerical simulations. Estimation of effective material properties of the thermoelectric module using manufacturer-reported performance characteristics is found to reduce the uncertainty in the calculation of module input power as compared to experimental measurements. A parametric optimization of the thermoelectric module and heat sink is carried out to maximize the coefficient of performance (COP) and achieve the required cooling capacity of the microprocessor. The effectiveness of the proposed methodology is demonstrated for cooling current high power microprocessors. At a const...
International Journal of Low-Carbon Technologies, 2021
The present article reports on the analysis of waste heat and condensate recovery from residentia... more The present article reports on the analysis of waste heat and condensate recovery from residential air conditioning (AC) units in different climatic regions in Saudi Arabia. Simulation results obtained using a transient dynamic model show that significant amounts of waste heat and water condensate are rejected to the environment in hot and humid climate regions. A multi-generation system for simultaneous cooling and pure water production using condensate and waste heat recovery is designed and implemented in TRNSYS environment. A refrigerant to water de-superheater is introduced after the compressor to extract energy from the high temperature superheated refrigerant gas for heating saline water that is used as a feed to drive an air gap membrane desalination unit. The production of pure water is analyzed for both batch and continuous cooling modes of the membrane desalination unit. The amount of pure water production shows the potential of proposed system to supply pure water requirements in hot and humid climates in Saudi Arabia. The monthly average coefficient of performance of multi-generation residential AC units with continuous cooling of desalination unit is shown to be improved by ∼6.61%. The monthly average gained output ratio of membrane desalination unit is higher than 1.14.
2020 IEEE 7th International Conference on Engineering Technologies and Applied Sciences (ICETAS), 2020
This paper studies a design of thermoelectric generator TEG used to recover heat from industrial ... more This paper studies a design of thermoelectric generator TEG used to recover heat from industrial flare. The design focuses on the optimum sizing of the TEG module as well as the optimum load resistance in order to maximize the power. Moreover, an experimental work has been conducted in order to study the accuracy of the analytical model. The analytical model is based on thermoelectric ideal equations and heat sink designed to maximize the heat dissipation. The accuracy of the TEG system increases when the effective material properties technique is being applied. The results then are being extrapolated to real flare sizing to view the total power production on the industrial plant.
Physica E: Low-dimensional Systems and Nanostructures, 2021
Abstract Polypyrrole (PPy) is a highly conducting polymer with favorable room temperature (RT) th... more Abstract Polypyrrole (PPy) is a highly conducting polymer with favorable room temperature (RT) thermoelectric (TE) properties. Recently, nanostructure forms of this polymer have been produced with various morphologies by using different surfactants; however, the effect of these morphologies on the TE figure of merit and TE performance has not been well described. In particular, the TE properties of PPy sheets/films composed of nanoparticles (SNPs) have not yet been investigated. In this work, PPy with various morphologies was synthesized using different surfactants. Nanoparticles, nanotubes , continuous sheets and SNPs were produced and characterized by well-known techniques. The structural and TE properties of the as-synthesized nanomaterials were investigated. The obtained results show that SNPs have improved TE properties compared to nanotubes and nanoparticles. The latter two forms have either higher or lower electrical and thermal conductivities than those of SNPs, which suppress their TE performance. The produced SNPs were able to overcome these limitations, as they have high electrical and low thermal conductivities, which result in a high figure of merit and enhanced TE performance. The best SNPs was found to have a power factor, thermal conductivity and figure of merit of 0.17 μV/m⋅K 2, 0.132 W/mK2 and 0.4 × 10−3 at room temperature, respectively. These results might be useful for developing future TE materials and devices.
Doped polypyrrole/functionalized multi-walled carbon nanotubes composites were synthesized in an ... more Doped polypyrrole/functionalized multi-walled carbon nanotubes composites were synthesized in an acidic medium using an in situ oxidative polymerization route. FeCl3 was utilized as an oxidizing agent and sodium dodecyl sulfate as a surfactant to produce 2-dimensional films. Thin films were fabricated from polypyrrole/functionalized multi-walled carbon nanotubes composites using the thermal evaporation technique and are inspected by various methods. The surface morphology of the thin film is characterized by computing the crystalline size and shape. The XRD study of [PPy] and [PPyCNs]NC as-deposited thin films showed that these polymers are merely a triclinic crystal structure with a space group P 1¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\overline{1}$$\end{document}. The crystallite size (D) value average is 74.24 nm for [PPyCNsF]NC. The direct energy gap values are decreased from 2.68 to 1.93 eV for [PPy] and [PPyCNs]NC as-deposited thin film, respectively. The optical features of the thin film were investigated. The optical constants and optical conductivity for the nanotubes composites were figured and interrelated by using experiment and TDDFT-DFT/DMOl3 simulation methods. The structural and optical parameters of the simulated nanocomposites as single isolated molecules are in reasonable agreement with the investigational work. The nanotube composite thin films exhibited encouraging results to be a worthy applicant for polymer solar cell requests.
Nearly 70% of the energy produced from automotive engines is released to the atmosphere in the fo... more Nearly 70% of the energy produced from automotive engines is released to the atmosphere in the form of waste energy. The recovery of this energy represents a vital challenge to engine designers primarily when a thermoelectric generator (TEG) is used, where the availability of a continuous, steady-state temperature and heat flow is essential. The potential of semi-truck engines presents an attractive application as many coaches and trucks are roaming motorways at steady-state conditions most of the time. This study presents an analytical thermal design and an experimental validation of the TEG system for waste heat recovery from the exhaust of semi-truck engines. The TEG system parameters were optimized to achieve the maximum power output. Experimental work was conducted on a specially constructed setup to validate the analytically obtained results. Both analytical and experimental results were found to be in good agreement with a marginal deviation, indicating the excellent accuracy...
The current work focuses on finding the optimum electrical load resistance of thermoelectric gene... more The current work focuses on finding the optimum electrical load resistance of thermoelectric generator system. The optimum load resistance and optimum geometric ratio of a thermoelectric module are obtained simultaneously by using an analytical method based on dimensional analysis. These parameters are optimized to provide the maximum possible output power of a thermoelectric module attached to two heat sinks. Subsequently, an experiment has been conducted in order to validate the accuracy of the analytical model where good agreement is observed. Moreover, by using the specifications of the thermoelectric module that are provided by manufacturer, the effective thermoelectric material properties can be obtained; these properties help estimate the impact of contact resistance and Thomson effect. Furthermore, generalized charts are presented in this study which can help designers to determine the optimum load resistance and geometry for maximum output power.
Hydrochloric acid doped poly (ortho-aminophenol-co-para-toluidine) as a conjugated semiconducting... more Hydrochloric acid doped poly (ortho-aminophenol-co-para-toluidine) as a conjugated semiconducting copolymer is synthesized in acidic medium via the oxidative polymerization method. The spin coating technique is applied to deposit with appropriate adhesion of doped copolymer thin film. The resulting doped poly (ortho-aminophenol-co-para-toluidine) (POAPT) thin film is characterized by the various techniques to explore its structural, morphological, and optical properties. Density-functional theory (DFT) calculations were implemented utilizing Cambridge Serial Total Energy Package (CASTEP) from Accelrys based on a plane-wave pseudopotential. The optical dispersion of poly (ortho-aminophenol-copara-toluidine) thin film is expressed in the single oscillator terms of Wemple-Didomenico (WD) model. The parameters E g is 2.02 eV, n and k (at 2.36 eV) are 1.73 and 3.27 ×10-8 , respectively, n ∞ is 1.633, λ o is 172.65 nm and S o is 2.126 nm-2. Based on the resulting data of optical analysis and conductivity the doped poly (ortho-aminophenol-co-para-toluidine) thin film was found to have promising applications in optoelectronic devices area.
Non-standardized forms of performance data is an issue designers encounter when dealing with ther... more Non-standardized forms of performance data is an issue designers encounter when dealing with thermoelectric module manufacturers. To assess a product's performance, experimental methods can be used as well as analytical modeling by using the material properties that are not usually revealed. The latter investigates theories using the guidelines given by the manufacturers. After analyzing the theories, the values are used to assess the performances of the thermoelectric modules. The samples then go through experimental testing to insure their validity. Finally, the analytical, experimental, and manufacturer-provided results are compared to find a common ground. The results shows good agreement where the most of the errors are less than 1%.
The optimum design of a thermoelectric system for application in car seat climate control has bee... more The optimum design of a thermoelectric system for application in car seat climate control has been modeled and its performance evaluated experimentally. The optimum design of the thermoelectric device combining two heat exchangers was obtained by using a newly developed optimization method based on the dimensional technique. Based on the analytical optimum design results, commercial thermoelectric cooler and heat sinks were selected to design and construct the climate control heat pump. This work focuses on testing the system performance in both cooling and heating modes to ensure accurate analytical modeling. Although the analytical performance was calculated using the simple ideal thermoelectric equations with effective thermoelectric material properties, it showed very good agreement with experiment for most operating conditions.
Hydrochloric acid doped poly ortho aminophenol (POAP) is prepared in a high acidic medium (pH0.6... more Hydrochloric acid doped poly ortho aminophenol (POAP) is prepared in a high acidic medium (pH0.6) using FeCl 3 as an oxidizing agent. The polymerization process is conducted in the presence of polyethylene glycol (PEG200) as a soft template at 25 ºC. The method pertains to the reduction of FeCl 3 by o-amino phenol (OAP) at room temperature. The obtained POAP polymer is soluble in common organic solvents such as dimethylformamide and chloroform. The resulting POAP is investigated by various analyzing techniques including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), proton nuclear magnetic resonance (1 HNMR), and scanning electron microscope (SEM). The analysis revealed that both quinoid and benzoid structures are existing in the polymer backbone. POAP thin film is fabricated and its optical properties are also investigated. Au/POAP/TiO 2 /p-Si/Al heterojunction solar cell is fabricated as well. The resulting average value of power conversion efficiency (PCE) of Au/POAP/TiO 2 /p-Si/Al heterojunction solar cell is found to be 4.28 %.
Abstract The current project is discussing the optimization of counter flow air-to-air thermoelec... more Abstract The current project is discussing the optimization of counter flow air-to-air thermoelectric air conditioners (TEAC) system. Previous work showed an analytical model with experimental validation of a unit cell of TEAC system. However, the focus of this work is to simulate the optimum design of a whole TEAC system from given inlet parameters (i.e., hot and cold air mass flow rates and ambient temperatures). The analytical model was built by combining an optimal design method with dimensional analysis, which was recently developed, and the thermal isolation method in order to optimize the thermoelectric parameters (i.e., electrical current supplied and the number of thermocouples or the geometric factor, simultaneously). Moreover, based on the designed model, an experiment was conducted in order to study the accuracy of the analytical model. Even though the analytical model was built based on the thermoelectric ideal equations, it shows a good agreement with the experiment. This agreement was mainly a result of the use of the thermoelectric effective material properties which are obtained from the measured maximum thermoelectric module parameters. Since the experiment validate the analytical model, this model provides uncomplicated method to study the optimum design at given inputs.
The optimization of thermoelectric air conditioners (TEAC) has been a challenging topic due to th... more The optimization of thermoelectric air conditioners (TEAC) has been a challenging topic due to the multitude of variables needed to be considered. The present work discusses the experimental validation of the optimum design for automotive air-to-air TEAC. The TEAC optimum design was obtained by using a new optimal design method with dimensional analysis that has been recently developed. The design constraints were obtained through a previous analytically study on the same topic. In order to simplify the problem, a unit cell that represents the entire TEAC system was analytically simulated and was experimentally tested. Moreover, commercial TEC modules and heat sinks were selected and tested based on the analytical optimum design results.
This work examines the validity of formulating the effective thermoelectric material properties a... more This work examines the validity of formulating the effective thermoelectric material properties as a way to predict thermoelectric module performance. The three maximum parameters (temperature difference, current, and cooling power) of a thermoelectric cooler were formulated on the basis of the hot junction temperature. Then, the effective material properties (Seebeck coefficient, electrical resistance, and thermal conductivity) were defined in terms of the three maximum parameters that were taken from either a commercial thermoelectric cooler module or the measurements. It is demonstrated that the simple standard equation with the effective material properties predicts well the performance curves of the four selected commercial products. Normalized parameters over the maximum parameters were also formulated to present the characteristics of the
This article reports on an experimental analysis and performance assessment of using thermoelectr... more This article reports on an experimental analysis and performance assessment of using thermoelectric generators (TEGs) for waste heat recovery from residential vapor compression refrigeration systems. The analysis shows that there is a good opportunity for waste heat recovery using TEGs by de-superheating refrigerant after the compressor. Design and manufacturing of a de-superheater unit consisting of a tube and plate heat exchanger and thermoelectric generator modules (HE-TEGs) have been performed and integrated in an experimental test rig of R134a refrigeration cycle. Experimental assessment of the performance parameters, as compared to the basic refrigeration system, reveals that the overall coefficient of performance (COP) using HE-TEGs desuperheater unit increases by values ranging from 17% to 32% depending on the condenser and evaporator loads. Exergy analysis shows that the enhancement is attributed to reduction in the exergy destruction in the condenser and compressor due to ...
Comparison between experiment and predicted junction temperatures vs. input current for (a) cold ... more Comparison between experiment and predicted junction temperatures vs. input current for (a) cold junction temperature and (b) hot junction temperature [37] ..... 6.12. Comparison between experiment and predicted cop and cold air temperature difference vs.
International Journal of Low-Carbon Technologies, 2021
The present article reports on the design, modeling and parametric optimization of a thermoelectr... more The present article reports on the design, modeling and parametric optimization of a thermoelectric cooling system for electronics applications. An analytical model based on energy equilibrium is developed for cooling a microprocessor using a thermoelectric module with an air-cooled finned heat sink. The proposed analytical model is validated by experimental measurements and by comparison with detailed 3D numerical simulations. Estimation of effective material properties of the thermoelectric module using manufacturer-reported performance characteristics is found to reduce the uncertainty in the calculation of module input power as compared to experimental measurements. A parametric optimization of the thermoelectric module and heat sink is carried out to maximize the coefficient of performance (COP) and achieve the required cooling capacity of the microprocessor. The effectiveness of the proposed methodology is demonstrated for cooling current high power microprocessors. At a const...
International Journal of Low-Carbon Technologies, 2021
The present article reports on the analysis of waste heat and condensate recovery from residentia... more The present article reports on the analysis of waste heat and condensate recovery from residential air conditioning (AC) units in different climatic regions in Saudi Arabia. Simulation results obtained using a transient dynamic model show that significant amounts of waste heat and water condensate are rejected to the environment in hot and humid climate regions. A multi-generation system for simultaneous cooling and pure water production using condensate and waste heat recovery is designed and implemented in TRNSYS environment. A refrigerant to water de-superheater is introduced after the compressor to extract energy from the high temperature superheated refrigerant gas for heating saline water that is used as a feed to drive an air gap membrane desalination unit. The production of pure water is analyzed for both batch and continuous cooling modes of the membrane desalination unit. The amount of pure water production shows the potential of proposed system to supply pure water requirements in hot and humid climates in Saudi Arabia. The monthly average coefficient of performance of multi-generation residential AC units with continuous cooling of desalination unit is shown to be improved by ∼6.61%. The monthly average gained output ratio of membrane desalination unit is higher than 1.14.
2020 IEEE 7th International Conference on Engineering Technologies and Applied Sciences (ICETAS), 2020
This paper studies a design of thermoelectric generator TEG used to recover heat from industrial ... more This paper studies a design of thermoelectric generator TEG used to recover heat from industrial flare. The design focuses on the optimum sizing of the TEG module as well as the optimum load resistance in order to maximize the power. Moreover, an experimental work has been conducted in order to study the accuracy of the analytical model. The analytical model is based on thermoelectric ideal equations and heat sink designed to maximize the heat dissipation. The accuracy of the TEG system increases when the effective material properties technique is being applied. The results then are being extrapolated to real flare sizing to view the total power production on the industrial plant.
Physica E: Low-dimensional Systems and Nanostructures, 2021
Abstract Polypyrrole (PPy) is a highly conducting polymer with favorable room temperature (RT) th... more Abstract Polypyrrole (PPy) is a highly conducting polymer with favorable room temperature (RT) thermoelectric (TE) properties. Recently, nanostructure forms of this polymer have been produced with various morphologies by using different surfactants; however, the effect of these morphologies on the TE figure of merit and TE performance has not been well described. In particular, the TE properties of PPy sheets/films composed of nanoparticles (SNPs) have not yet been investigated. In this work, PPy with various morphologies was synthesized using different surfactants. Nanoparticles, nanotubes , continuous sheets and SNPs were produced and characterized by well-known techniques. The structural and TE properties of the as-synthesized nanomaterials were investigated. The obtained results show that SNPs have improved TE properties compared to nanotubes and nanoparticles. The latter two forms have either higher or lower electrical and thermal conductivities than those of SNPs, which suppress their TE performance. The produced SNPs were able to overcome these limitations, as they have high electrical and low thermal conductivities, which result in a high figure of merit and enhanced TE performance. The best SNPs was found to have a power factor, thermal conductivity and figure of merit of 0.17 μV/m⋅K 2, 0.132 W/mK2 and 0.4 × 10−3 at room temperature, respectively. These results might be useful for developing future TE materials and devices.
Doped polypyrrole/functionalized multi-walled carbon nanotubes composites were synthesized in an ... more Doped polypyrrole/functionalized multi-walled carbon nanotubes composites were synthesized in an acidic medium using an in situ oxidative polymerization route. FeCl3 was utilized as an oxidizing agent and sodium dodecyl sulfate as a surfactant to produce 2-dimensional films. Thin films were fabricated from polypyrrole/functionalized multi-walled carbon nanotubes composites using the thermal evaporation technique and are inspected by various methods. The surface morphology of the thin film is characterized by computing the crystalline size and shape. The XRD study of [PPy] and [PPyCNs]NC as-deposited thin films showed that these polymers are merely a triclinic crystal structure with a space group P 1¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\overline{1}$$\end{document}. The crystallite size (D) value average is 74.24 nm for [PPyCNsF]NC. The direct energy gap values are decreased from 2.68 to 1.93 eV for [PPy] and [PPyCNs]NC as-deposited thin film, respectively. The optical features of the thin film were investigated. The optical constants and optical conductivity for the nanotubes composites were figured and interrelated by using experiment and TDDFT-DFT/DMOl3 simulation methods. The structural and optical parameters of the simulated nanocomposites as single isolated molecules are in reasonable agreement with the investigational work. The nanotube composite thin films exhibited encouraging results to be a worthy applicant for polymer solar cell requests.
Nearly 70% of the energy produced from automotive engines is released to the atmosphere in the fo... more Nearly 70% of the energy produced from automotive engines is released to the atmosphere in the form of waste energy. The recovery of this energy represents a vital challenge to engine designers primarily when a thermoelectric generator (TEG) is used, where the availability of a continuous, steady-state temperature and heat flow is essential. The potential of semi-truck engines presents an attractive application as many coaches and trucks are roaming motorways at steady-state conditions most of the time. This study presents an analytical thermal design and an experimental validation of the TEG system for waste heat recovery from the exhaust of semi-truck engines. The TEG system parameters were optimized to achieve the maximum power output. Experimental work was conducted on a specially constructed setup to validate the analytically obtained results. Both analytical and experimental results were found to be in good agreement with a marginal deviation, indicating the excellent accuracy...
The current work focuses on finding the optimum electrical load resistance of thermoelectric gene... more The current work focuses on finding the optimum electrical load resistance of thermoelectric generator system. The optimum load resistance and optimum geometric ratio of a thermoelectric module are obtained simultaneously by using an analytical method based on dimensional analysis. These parameters are optimized to provide the maximum possible output power of a thermoelectric module attached to two heat sinks. Subsequently, an experiment has been conducted in order to validate the accuracy of the analytical model where good agreement is observed. Moreover, by using the specifications of the thermoelectric module that are provided by manufacturer, the effective thermoelectric material properties can be obtained; these properties help estimate the impact of contact resistance and Thomson effect. Furthermore, generalized charts are presented in this study which can help designers to determine the optimum load resistance and geometry for maximum output power.
Hydrochloric acid doped poly (ortho-aminophenol-co-para-toluidine) as a conjugated semiconducting... more Hydrochloric acid doped poly (ortho-aminophenol-co-para-toluidine) as a conjugated semiconducting copolymer is synthesized in acidic medium via the oxidative polymerization method. The spin coating technique is applied to deposit with appropriate adhesion of doped copolymer thin film. The resulting doped poly (ortho-aminophenol-co-para-toluidine) (POAPT) thin film is characterized by the various techniques to explore its structural, morphological, and optical properties. Density-functional theory (DFT) calculations were implemented utilizing Cambridge Serial Total Energy Package (CASTEP) from Accelrys based on a plane-wave pseudopotential. The optical dispersion of poly (ortho-aminophenol-copara-toluidine) thin film is expressed in the single oscillator terms of Wemple-Didomenico (WD) model. The parameters E g is 2.02 eV, n and k (at 2.36 eV) are 1.73 and 3.27 ×10-8 , respectively, n ∞ is 1.633, λ o is 172.65 nm and S o is 2.126 nm-2. Based on the resulting data of optical analysis and conductivity the doped poly (ortho-aminophenol-co-para-toluidine) thin film was found to have promising applications in optoelectronic devices area.
Non-standardized forms of performance data is an issue designers encounter when dealing with ther... more Non-standardized forms of performance data is an issue designers encounter when dealing with thermoelectric module manufacturers. To assess a product's performance, experimental methods can be used as well as analytical modeling by using the material properties that are not usually revealed. The latter investigates theories using the guidelines given by the manufacturers. After analyzing the theories, the values are used to assess the performances of the thermoelectric modules. The samples then go through experimental testing to insure their validity. Finally, the analytical, experimental, and manufacturer-provided results are compared to find a common ground. The results shows good agreement where the most of the errors are less than 1%.
The optimum design of a thermoelectric system for application in car seat climate control has bee... more The optimum design of a thermoelectric system for application in car seat climate control has been modeled and its performance evaluated experimentally. The optimum design of the thermoelectric device combining two heat exchangers was obtained by using a newly developed optimization method based on the dimensional technique. Based on the analytical optimum design results, commercial thermoelectric cooler and heat sinks were selected to design and construct the climate control heat pump. This work focuses on testing the system performance in both cooling and heating modes to ensure accurate analytical modeling. Although the analytical performance was calculated using the simple ideal thermoelectric equations with effective thermoelectric material properties, it showed very good agreement with experiment for most operating conditions.
Hydrochloric acid doped poly ortho aminophenol (POAP) is prepared in a high acidic medium (pH0.6... more Hydrochloric acid doped poly ortho aminophenol (POAP) is prepared in a high acidic medium (pH0.6) using FeCl 3 as an oxidizing agent. The polymerization process is conducted in the presence of polyethylene glycol (PEG200) as a soft template at 25 ºC. The method pertains to the reduction of FeCl 3 by o-amino phenol (OAP) at room temperature. The obtained POAP polymer is soluble in common organic solvents such as dimethylformamide and chloroform. The resulting POAP is investigated by various analyzing techniques including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), proton nuclear magnetic resonance (1 HNMR), and scanning electron microscope (SEM). The analysis revealed that both quinoid and benzoid structures are existing in the polymer backbone. POAP thin film is fabricated and its optical properties are also investigated. Au/POAP/TiO 2 /p-Si/Al heterojunction solar cell is fabricated as well. The resulting average value of power conversion efficiency (PCE) of Au/POAP/TiO 2 /p-Si/Al heterojunction solar cell is found to be 4.28 %.
Abstract The current project is discussing the optimization of counter flow air-to-air thermoelec... more Abstract The current project is discussing the optimization of counter flow air-to-air thermoelectric air conditioners (TEAC) system. Previous work showed an analytical model with experimental validation of a unit cell of TEAC system. However, the focus of this work is to simulate the optimum design of a whole TEAC system from given inlet parameters (i.e., hot and cold air mass flow rates and ambient temperatures). The analytical model was built by combining an optimal design method with dimensional analysis, which was recently developed, and the thermal isolation method in order to optimize the thermoelectric parameters (i.e., electrical current supplied and the number of thermocouples or the geometric factor, simultaneously). Moreover, based on the designed model, an experiment was conducted in order to study the accuracy of the analytical model. Even though the analytical model was built based on the thermoelectric ideal equations, it shows a good agreement with the experiment. This agreement was mainly a result of the use of the thermoelectric effective material properties which are obtained from the measured maximum thermoelectric module parameters. Since the experiment validate the analytical model, this model provides uncomplicated method to study the optimum design at given inputs.
The optimization of thermoelectric air conditioners (TEAC) has been a challenging topic due to th... more The optimization of thermoelectric air conditioners (TEAC) has been a challenging topic due to the multitude of variables needed to be considered. The present work discusses the experimental validation of the optimum design for automotive air-to-air TEAC. The TEAC optimum design was obtained by using a new optimal design method with dimensional analysis that has been recently developed. The design constraints were obtained through a previous analytically study on the same topic. In order to simplify the problem, a unit cell that represents the entire TEAC system was analytically simulated and was experimentally tested. Moreover, commercial TEC modules and heat sinks were selected and tested based on the analytical optimum design results.
This work examines the validity of formulating the effective thermoelectric material properties a... more This work examines the validity of formulating the effective thermoelectric material properties as a way to predict thermoelectric module performance. The three maximum parameters (temperature difference, current, and cooling power) of a thermoelectric cooler were formulated on the basis of the hot junction temperature. Then, the effective material properties (Seebeck coefficient, electrical resistance, and thermal conductivity) were defined in terms of the three maximum parameters that were taken from either a commercial thermoelectric cooler module or the measurements. It is demonstrated that the simple standard equation with the effective material properties predicts well the performance curves of the four selected commercial products. Normalized parameters over the maximum parameters were also formulated to present the characteristics of the
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