Weirs are among the most important hydraulic structures in water engineering, playing a key role in flow control and measurement, water level regulation, and ensuring hydraulic safety in open channels and hydraulic systems. Among various types of weirs, sharp-crested weirs have always attracted significant attention due to their simple construction, acceptable accuracy in discharge measurement, and wide application in open channels. However, channel width limitations and the increasing demand for higher discharge capacity have made the optimization of the geometric configuration of these weirs increasingly important. One effective approach in this regard is the use of inclined sharp-crested weirs combined with transverse crest slope modification, which can increase the effective crest length and improve hydraulic performance. In this study, the hydraulic performance of an inclined sharp-crested weir with a non-uniform transverse slope was numerically investigated. The main objective of the research was to evaluate the effects of the weir inclination angle and non-uniform transverse slope on flow patterns, velocity and pressure distributions, free-surface behavior, and the discharge coefficient. To achieve this goal, three-dimensional free-surface flow simulations were carried out using the FLOW-3D HYDRO software (version 2023R2). The RNG k–? turbulence model was employed to close the Reynolds-averaged Navier–Stokes equations, as it provides suitable accuracy for simulating three-dimensional turbulent flows, regions with high velocity gradients, and flow separation zones. The computational domain consisted of a three-dimensional model of the sharp-crested weir with different inclination angles and transverse slope configurations. Appropriate boundary conditions for inlet, outlet, walls, and the free surface were defined based on experimental conditions. Prior to the main simulations, a grid sensitivity analysis was performed to select an optimal mesh that ensured sufficient accuracy while maintaining reasonable computational cost. To validate the numerical model, simulation results were compared with available experimental data. Four different weir configurations with varying geometric and angular conditions were simulated. The comparison of upstream water depth between numerical and experimental results showed that the relative error was less than 2% in all cases, confirming the reliability and accuracy of the numerical model. The simulation results indicate that applying a non-uniform transverse slope to the crest of an inclined sharp-crested weir significantly affects flow behavior. Increasing the inclination angle enhances the effective crest length and increases discharge capacity, although a slight reduction in the discharge coefficient was observed in some cases. Furthermore, the results demonstrate that a variable transverse slope can lead to a more uniform flow distribution across the channel width, reduce secondary flows, and improve free-surface stability. Overall, the combined use of an inclined crest and a non-uniform transverse slope can be considered an effective approach for improving the hydraulic performance of sharp-crested weirs in hydraulic structure design.  

Abstract Due to population growth and the industrialization of today's societies, the global demand for energy is continuously increasing. Fossil fuel sources, including crude oil, coal, and natural gas, are among the most important sources of energy in Iran. In this regard, the extraction of natural resources and the excessive consumption of fossil fuels not only lead to the depletion of these natural gifts, but also cause irreparable impacts to the environment such as the destruction of the ozone layer, air pollution, and global warming. do In such a way that human environmental effects have caused the earth to warm by 2 degrees Fahrenheit as a result of the heating related to carbon dioxide caused by the burning of fossil fuels and natural gases. Since the industry sector has a significant contribution to the country's final energy consumption, reducing energy consumption in this sector is an effective step towards optimizing energy consumption and reducing greenhouse gas emissions and environmental pollution, because the world Today, it is facing an energy crisis and very dangerous environmental challenges. Therefore, this thesis aims to design a building model for industrial poultry farms in Hersin city so that it can reduce the amount of energy consumption in these units by using appropriate solutions. In this regard, by using a field research field, receiving information in the form of a library, reading books, theses, and receiving scientific and research articles via the internet, it has been compiled and studied. Therefore, using the obtained information, an industrial unit with the use of meat poultry has been designed and simulated by computer and DesignBuilder software. Based on this, by applying energy consumption optimization solutions and the results obtained from it, the energy consumption compared to the simulated building has been investigated and compared, so that the optimized building has been able to The rate of electricity consumption and the rate of gas consumption have been reduced. Keywords: energy, poultry farming, environmental pollution, industrial architecture  

   Abstract The increase in population and the advancement of technology in the 20th century has accelerated the process of industrialization in countries. This increase required a lot of energy supply, and for this reason, industrial societies have increasingly used fossil fuels. Indiscriminate use of this type of fuel has led to destructive environmental effects and extensive changes in weather and climate worldwide. The concentration of greenhouse gases such as carbon dioxide, methane and other greenhouse gases is increasing due to human activities. This issue has raised concerns about the increase in the earth's temperature. According to research, it is likely that the Earth's temperature will increase by 1 to 5 degrees Celsius during the current century, which is a trend in the global average temperature that is outside the natural variation of temperature changes in the last thousand years. In this thesis, a theoretical research has been conducted in which simulation has been used and through that, the required information has been obtained through library resources, climate data, weather information and so on, Collected. This information has been simulated by computer using Designbuilder and Polysun software, and using the obtained results, a low-energy industrial unit (zero energy) has been designed in the textile industry. This building has been able to meet its energy needs using renewable energy. And it has also had zero annual results in energy consumption and production. The results obtained from the simulations showed that after applying energy consumption optimization strategies, the building consumption in the areas of cooling, heating, lighting, hot water consumption and equipment used for a full year, decreased by 61.35 percent compared to the reference building and has reached 68.45 KWh/m2. Also, by the solar system installed on the roof of the building, this system has been able to produce 76.70 KWh/m2 of electrical energy. According to the results, the difference between the amount of energy consumed and the amount of energy produced showed that in addition to confirming the achievement of a zero energy building, the solar system produced 8.25 KWh/m2 in excess of the energy requirement. Keywords: Architectural Design of Industrial Units, Textile Industry, Zero Energy, Kermanshah

   Identification of two-phase flows and its Taylor bubble characteristics is one of the most important parameters designing industrial installations for intermittent gas-liquid two-phase flow. Also, it is important to know the characteristics of two-phase flow in order to improve the exploitation of oil wells and to optimize the process of maintenance and repair of flow transmission lines with the purpose of cleaning pipelines along with reducing its costs in the oil and gas industries and in chemical and electronic chip cooling industry. The purpose of this research to analyze bubble flow patterns, achieve two-phase flow patterns of water and air using numerous experimental tests and investigate the effect of pulsating gas flow on the characteristics of the Taylor flow field (Taylor bubble length and velocity) under different two-phase inlet conditions air and water done in the form of an upward parallel flow. The range of studied apparent velocity Gas and Liquid phase is 0.12-0.28 m/s and 0.05-0.25 m/s, respectively, and the pulsating gas flow frequency is 0.25-0.4 Hz. In this study, by examining more than 100 different apparent velocities for the phases, three patterns of bubble, slug and churn were observed and a map of the two-phase flow pattern of water and air was drawn. Also, the effect of pulsating gas flow on the length of the Taylor bubble was investigated in 150 different experiments, and the results of this study showed that with the increase of the pulsating gas flow and the frequency, the stability of the Taylor bubble flow increased and the length of the Taylor bubble decreased significantly. So that at the frequencies of 0.25, 0.5, 1, 2 and 4 Hz, respectively, the maximum bubble length was observed at the liquid velocity of 0.12 m/s and gas velocity of 0.25 m/s are 455.5, 367, 313.1, 286.3 and 244.2 mm.   Also, at a constant frequency, the length of the Taylor bubble increases with the increase of the apparent velocity of the gas phase. For example, at a constant frequency of 1 Hz and a liquid velocity of 0.12 m/s, the bubble length increased from 147.8 mm to 1.313 mm when the gas velocity increased from 0.10 to 0.25 m/s. In addition, in this research, with the help of image processing, the movement speed of the Taylor bubble was measured and determined for 15 different apparent speeds using the speed measurement technique. Comparison of the obtained linear equation with previous studies showed that the relationship has a good fitting accuracy. The results of the present work proves that the pulsating gas flow technique enables the control of the gas-liquid Taylor bubble flow pattern and the stability of the motion of the Taylor bubbles, which will be very useful for future industrial applications in gas-liquid reactions.

   Abstract Today, the expansion of the use of the Internet has made it possible for millions of users around the world to access online social networks. On the other hand, these networks have been in the focus of users' attention in the dissemination of information, especially in areas such as viral marketing advertising, improving recommender systems, transferring time-sensitive information, guiding public opinion, promoting national security, sociology, etc. One of the important issues surrounding the dissemination of information in online social networks is the issue of effective dissemination of the message at a suitable speed. For this purpose, it is necessary to identify the influential users in a suitable way. In this thesis, it is proposed to identify influential people based on the reactive information of users and according to their sphere of influence. For this purpose, first, the value of network communication is determined based on the reactive information of users (reply and retweet), and then, the structure of the network is divided into its constituent communities. In the next step, centrality criteria are used to evaluate the importance of each member of the community, and at the end, influential nodes are identified in their sphere of influence. The effectiveness of the proposed method using a real database that includes the retweet and reply information of Twitter users; has been tested. Due to the lack of a database that has the tagging of influential people and reactive information at the same time; from one of the methods of information dissemination in social networks that has an acceptable correlation with the proposed method; Used. At the end, the obtained results are compared with previous similar methods. The results of the evaluations showed that the method proposed in this thesis can identify effective users with more accuracy, efficiency and speed. Also, the evaluation results showed that the proposed method can achieve 87.33% detection accuracy in identifying effective users, which shows an improvement of at least 13% compared to the compared methods.    Keywords: social network analysis, identification of influential users, identification of communities, graph analysis.   

يكي از معيارهاي مورد توجه طراحان و معماران، افزايش اجتماع پذيري و كاهشاجتماع گريزي در مقياس يك محله است. در چندين سال اخير اماكني با نام سراي محله درمحلات شهر تهران شكل گرفته است. سراي محله موجبات پيشرفت و تحكم پيوندهاي اجتماعيدر محله را براي ساكنين فراهم فراهم مي نمايد. اين فرصت در معماري مي تواند بهوسيله رفع يك نياز اجباري آغاز شود، با روابط اجتماعي اهالي محله پيشرفت كرده و باپيوند هاي اجتماعي و فرهنگي بين اهالي محله ادامه يابد. اين پايان نامه با هدفايجاد و ارتقاء اجتماع پذيري در محله چيتگر به واسطه طراحي سراي محله شكل گرفتهاست. مباني نظري پژوهش حاضر با روش توصيفي تحليلي و ابزار گردآوري مطالعاتكتابخانه اي و اسنادي صورت گرفته و سپس مولفه ها و ابعاد مورد نظر در زمينه اجتماعپذيري مشخص گرديد. در ادامه پرسشنامه اي بر مبناي همان مولفه ها و ابعاد طراحي شد.ميزان پايايي پرسشنامه براساس 30 نمونه ابتدايي و طبق فرمول كرونباخ محاسبه گرديد.حجم نمونه مورد نظر با استفاده از فرمول كوكران محاسبه و پرسشنامه ميان 473 نفر ازافراد محله توزيع شد. سپس براي تجزيه و تحليل داده ها از نرم افزار    استفاده شد و پس از تحليل فرضيهها ميزان تاثيرگذاري هر 6 بعد (زيرمجموعه دو مولفه اصلي اجتماع پذيري (كالبدي وفعاليتي)) بر اجتماع پذيري سراي محله بدست آمد و با ارائه راهكارهاي مناسب ومطلوب، جهت طراحي سراي محله بكار گرفته شد.  

The rapid growth of the population, the expansion of cities and the development of industry caused the need of humans for fossil fuels, which brought consequences such as the emission of greenhouse gases, which subsequently caused an increase in air pollution, global warming, destruction of forests, melting The formation of natural glaciers, the expansion of deserts, etc. Along with other sectors that consume energy, the building takes a large part of it. Because providing thermal comfort, heating and cooling the indoor space depends on the consumption of a lot of energy. Also, in the humid temperate regions of our country, such as the Mazandaran region, due to the high humidity, a large part of the energy is spent on ventilation, heating and cooling, which itself plays an important role. in the emission of greenhouse gases and global warming. Therefore, the importance of this thesis is in providing suitable solutions and models to reduce energy consumption and improve the level of satisfaction of the residents, it is also possible to benefit from the appropriate design of the building according to the climatic conditions of the region by using the methods of library studies and simulation. Research method This thesis is a combination and is done by descriptive-analytical method, case study and modeling using modeling software (such as Design Builder and Ecotech), the available documents will be collected in a library method. This thesis is looking for solutions to achieve sustainable architecture, as well as applying techniques in line with the region's climate to create thermal comfort and natural ventilation.  

  In this dissertation, the designs of antennas with two bands and two polarizations have been studied. In this study, three different and new designs in the field of multiple antennas are presented. The simulations for all three antennas were examined in ansys hfss software and the antennas were evaluated and compared with each other.The structure of the designed antennas consists of an FR4 substrate and two or four 50 ohm power lines and an improved DGS (incomplete ground plate). The first proposed structure is a square antenna with dual patch. In Figure 4-10, this antenna is made using FR4 substrate with a thickness of less than 1 mm and a dielectric constant of 4.4 and a loss tangent of 0.022, and the overall dimensions of the substrate are 32 × 32 mm2. This structure is powered by a 50 ohm microstrip power line. According to the theory, patch antennas are located at the bottom of the substrate, the defective ground plate or DGS, and at the top of the substrate, the radiation patch and the microstrip power line. Where the measured bandwidth was 4.2 GHz equal to 2.86 GHz (3.59-6.53 GHz). And the measured bandwidth is 9 GHz equal to 3.08 GHz (7.05 - 10.13 GHz).For the second simulation, by creating a circular patch with a thickness of 10 mm, a suitable and practical bandwidth can be obtained from the antenna. At 3.5 GHz, the impedance bandwidth is approximately equal to 2.7 GHz, and at 10 GHz, the impedance bandwidth is equal to 4 GHz, which is It is considered a desirable band.To design the third design in the final antenna structure shown in Figure (32-4), the structure has an impedance bandwidth of 5.076 (3.5030 - 8.5790) GHz and 4.935 (11.587 - 16.522) GHz. The proposed antenna configuration creates a circular polarization with a phase difference of 90 degrees, which has many applications in the industry.

  The stabilization of the slope isone of the most important issues in geotechnical engineering. Theoccurrence of instability and slip in the natural and artificial slopes is oneof the phenomena that occur in many parts of the world in many cases. The slopefailure can occur due to natural factors such as soil mass weight and rainfalleffects or due to dynamic factors such as earthquakes. Stabilization of theslopes is done using various methods such as reinforcement with piles andanchors, and therefore the analysis of slope stability and determining the bestplace to install piles or anchors in it is one of the serious challenges ingeotechnical engineering. In this research, the optimal location for pileinstallation and the best anchor installation angle on soil slopes areinvestigated using strain field and shear stresses, which is a new work. Theamount of factor of safety is determined using the limit equilibrium method andthe strain field and shear stress are determined using the finite elementmethod. The benchmark used in the analyze is the Mohr Columb benchmark. Theresults showed that installing the pile in the field of zero strains or theminimum amount of strain results in the highest amount of factor of safety. Theresults also showed that the anchor installation in the field of minimum shearstresses and strains leads to the highest amount of factor of safety in theslope so that the anchor can use its maximum tensile capacity. The bestinstallation angle of the anchor relative to the horizon axis is about 5 to 15degrees. The results of this research are compared with the results of theprevious technical literature, which are in good agreement with each other.Considering the field of strains and shear stresses on soil slopes can providemore confidence for its stabilization.The stabilization of the slope isone of the most important issues in geotechnical engineering. Theoccurrence of instability and slip in the natural and artificial slopes is oneof the phenomena that occur in many parts of the world in many cases. The slopefailure can occur due to natural factors such as soil mass weight and rainfalleffects or due to dynamic factors such as earthquakes. Stabilization of theslopes is done using various methods such as reinforcement with piles andanchors, and therefore the analysis of slope stability and determining the bestplace to install piles or anchors in it is one of the serious challenges ingeotechnical engineering. In this research, the optimal location for pileinstallation and the best anchor installation angle on soil slopes areinvestigated using strain field and shear stresses, which is a new work. Theamount of factor of safety is determined using the limit equilibrium method andthe strain field and shear stress are determined using the finite elementmethod. The benchmark used in the analyze is the Mohr Columb benchmark. Theresults showed that installing the pile in the field of zero strains or theminimum amount of strain results in the highest amount of factor of safety. Theresults also showed that the anchor installation in the field of minimum shearstresses and strains leads to the highest amount of factor of safety in theslope so that the anchor can use its maximum tensile capacity. The bestinstallation angle of the anchor relative to the horizon axis is about 5 to 15degrees. The results of this research are compared with the results of theprevious technical literature, which are in good agreement with each other.Considering the field of strains and shear stresses on soil slopes can providemore confidence for its stabilization.

چكيده مغز انسان پيچيده ترين سيستم هستي است كه از ويژگي هاي منحصر به فردي برخوردار است. طي چند دهه اخير ، پژوهشگران سعي داشته اند تا با الهام گرفتن از مغز و نحوه عملكرد آن در پردازش اطلاعات ، سيستم هايي مشابه آن ايجاد كنند . يكي از ويژگي هاي مهم مغز توانايي خود تعميري و قابليت تحمل خطاست ؛ به طوري كه در صورت‌ آسيب ديدن چند سيناپس ، به دليل وجود سلول هايي به نام آستروسيت و از طريق سيناپس هاي سالم باقي مانده ،   سيستم عملكرد خود را در حد قابل قبولي حفظ مي كند . از آن جا كه سلول هاي عصبي در محيطي تصادفي فعاليت مي كنند ، وجود نويز يك مسئله غير قابل اجتناب است . به همين دليل در اين پروژه براي اولين بار به بررسي تاثير نويز در شبكه آستروسيت – نورون خود تعمير پرداخته شده است . با وجود اعمال نويز به جريان نورون ها ، سيستم هم چنان از توانايي خود تعميري برخوردار است و از طريق فيدبك غير مستقيم از سلول آستروسيت اثرات مخرب سيناپس هاي آسيب ديده را تا حدودي جبران مي كند . نتايج نشان مي دهند كه با وجود حضور نويز در جريان نورون ها و اعمال 80 درصد خطا به شبكه ، سلول آستروسيت هم چنان سعي در جبران خطا دارد و تا حد امكان فركانس هدف را حفظ مي نمايد .   

Every day a large number of comments are published by users on the web, especially on social networks, online review sites in forums and social networks. Due to the huge volume of this data and textual information, their analysis by humans is very difficult, time consuming and practically impossible; so we need a system that can automatically analyze comments. Sentiment analysis is the best solution to this problem. Sentiment analysis is a subset of natural language processing. And it is a process that examines people's concerns, views, and feelings by identifying the positive, negative, and neutral aspects of writing. The corona virus has become a storm on social media. As awareness of this disease increases, messages and posts confirm its existence. The social network Twitter has shown a similar effect to the number of messages related to Covid19. Which has had unprecedented growth in recent times. In this study, the analysis of Twitter Persian messages about the coronavirus was performed using machine learning. The success of machine learning has been discussed in many applications due to its ability to automatically extract features and learn complex patterns. The purpose of this study is to provide a model for analyzing and classifying the Sentiment of Twitter users using machine learning algorithms. In this research, using machine learning algorithms such as decision tree, SVM, logistic regression to approach the emotions of Persian tweets, an acceptable result has been obtained. Similarly, the accuracy of the decision tree algorithm was 83%, the support vector machine 81% and the logistic regression 77%. The decision tree algorithm has the best accuracy. Keywords: Sentiment analysis, Coronavirus pandemic, Twitter social networks, Machine learning.   

Choosing an optimal filteration system can reduce operating, repair and breakdown costs in many industries. If the suspended particles in the fluid are magnetic ones, magnetic filters can be used to separate them. Since internal magnetic filters are not able to separate FeS particles and other sub-micron particles, the use of high gradient magnetic filters is suggested as a solution. An important parameter in evaluation of these filters is the rate of adsorption of suspended particles in the liquid. Therefore, in this research, with the aim of COMSOL simulation software, the amount of particle adsorption and the effect of effective parameters on this parameter have been investigated. In both two-dimensional and three-dimensional simulations, a transverse configuration with a constant matrix diameter and a constant magnetic flux density is used. Important parameters of this research are the Reynolds number of the flow, the transverse distance of the rod matrices and the particle diameter. In three-dimensional analysis, according to the given variable parameters, the horizontal distance of the matrices and Reynolds number play an important role in the amount of particle adsorption, so that for horizontal distances greater than H = 1.4, the particle adsorption rate is significantly reduced, and the percentage Particle absorption is below 27%. It was observed that changing the particle diameter has less effect on the particle adsorption rate. The highest particle adsorption in the fluid occurs with the magnetic field strength of 1 Tesla with a rectangular arrangement for the horizontal distance H = 1.4 and the Reynolds number Re = 2, which has an adsorption rate of about 35%. The absorption rate of particles in the three-dimensional state is approximately one-half that of the absorption in the two-dimensional state. This can be explained due to the fact that all variables in two-dimensional and three-dimensional simulation were the same. Therefore, the same number of particles is considered in both geometries leading different values of adsorption.   

Performance evaluation of unbounded fiber-reinforced elastomeric isolators against wind

  AbstractWith attention to the development of new sciences, in particular electronic science and telecommunication, radio waves (radio communications), the size and physical size of high-capacity components will be smaller and smaller in integrated circuits, and these changes also affect the unwanted (noise) signals in the structure. As a result, we need high-performance filters to eliminate these unwanted waves. There are many errors in the integrated circuits due to the high frequencies, and also have unusual dimensions and size. Using the microstrip technique is very suitable for using a substrate (dielectric) substrate. For use in microwave integrated circuit circuits. In this dissertation, a low-pass microprocessor filter with very small size, a wide bandwidth and good return loss are presented.After designing and using the ADS (Advanced Design System) software and comparing the simulated and measured results, the values are acceptable.

 B

  AbstractIn this research, we study the effects of climate change on climatic variables of precipitation and temperature in the upcoming period and the effect of predicted changes on Chaghchmal plain groundwater levels in the next two 20-year periods. For this purpose and in order to simulate the aquifer, the GMS subterranean water model has been used. During the calibration period for the 18 month period (March 2009 to September 2008), the error rates for the two Mangram and non-stable models are MEX and MAE respectively. Also, verification The model was also carried out during the 18 month period (September 2011- April 2010) and the amount of RMSE and MAE indicators were obtained respectively. Also, to study the effect of climate change on the fluctuations of groundwater level of the region in the upcoming period, six AOGCM models under three scenarios A2, A1B and B1 and two probability levels of 90 and 50%, and with regard to the uncertainty of the general circulation models, prediction of climatic variables And temperature were paid. The LARS_WG model and the proportional method were used for mapping and localization of climate parameters. The predicted climatic variables for scenarios A2, A1B and B1 and two probabilities of 90% and 50% respectively, changes for the mean long-term temperature of 0.65 +, 0.653 +, 0.653 +, -0.04 and +0.6 ° C, and the long-term average changes The precipitation was -0.15.2.06 -, + 2.25, -30.2 and -0.095 percent during the period of 2011-2030, and the same for long-term changes in temperature +2, + 2.2.1.55 +, + 0.98 and +2.3 ° C, and average long-term variations of rainfall -17, -23.7, -18.3, -46 and -13.8% during the statistical period of 2065-2046. Ultimately, fluctuations due to climate change on aquifer levels were identified under scenarios. Based on the results, groundwater level under the scenarios A2, A1B and B1 and two probabilistic levels of 90 and 50 percent for the periods 2011-2030 and 2046-2046 compared to the period 1996-2015 averaged between -1.55 to -1.83 meters Drop showed In view of these changes in order to adapt and reduce the negative effects of climate change on the region, using the proper management of water resources and taking into account all aspects of agriculture, drinking, industrial and environmental uses, the effects of climate change on the water resources of the region Castells, in order to keep these resources as good aspossible.   Key word: Groundwater balance, Climate change, AOGCM general circulation model, Climate scenarios, Uncertainty, GMS model, LARS_WG model.

study

بهينه سازي كنترل كننده ها توسط الگوريتم بهينه سازي فاخته دريك ريز شبكه تركيبي درحضور چرخ طيار به منظور كنترل فركانس

  Thermoelectric devices produce electricity if a temperature gradient is applied to them (direct effect), and vice versa, by applying an electric current generate temperature (inverse effect).These devices are composed of a number of n-type and p-type semiconductor junctions connected electrically in series and thermally in parallel. If an electric current is applied to a thermoelectric cooler, heat is transferred from one side of the thermoelectric cooler to the other side. Therefore, one face of the thermoelectric cooler is cooled and the opposite face is heated. This study aims to investigate the effect of Piezo-fan boundary conditions on the efficiency of thermoelectric refrigerators. Piezoelectric fans are vibrating beams, disks, or plates whose vibratory motion is actuated using a piezoelectric material. Typically they consist of a flexible fan blade to which the piezoelectric element is bonded. By applying an alternating input signal to the piezoelectric element, beam begins to oscillate and induce a flow in the surrounding fluid. This could be used enhance heat transfer. Numerical results show that the maximum convection heat transfer coefficient in which fan tip to the wall distance is 1.5 mm and the wall is experiencing a constant thermal flux of 650 W/m2 is 73.55 W / m2.K. The boundary conditions imposing on thermoelectric elements affect their efficiency and by altering it the temperature of the insulated end could reach 73.66 Kelvin relative to ambient temperature. The results show that using a cooling system consisting of a heat sink and Piezo-fan on the hot end could meet the refrigerators thermal requirements. Depending on the heat sink type and the Piezo-fan configuration, the refrigerators performance would be different. Namely, a cooling system consisting of a pin-fin heat sink and a vertical arrangement of Piezo-fans has increased the refrigerators effective electric current range by 6.5% and has increased the maximum temperature drop by 8.4% with the cooling flux to be 20,000 watts W/m2.