List of Articles Mehdi Jahangiri

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  1 - Effect of wind speed on the drag force and wall shear stress of domes in historical mosques of Iran: a case study
  Iman Pishkar Mehdi Jahangiri Rouhollah Yadollahi Farsani Ayoub Khosravi Farsani
  20.1001.1.27834441.2023.15.2.6.5
  Climatic conditions have a great impact on the erosion of the coverage and the materials destruction of the dome gradually. Therefore, studying the shape and form of the dome in historic mosques can greatly assist to identify the affected points of the different types o More

  Climatic conditions have a great impact on the erosion of the coverage and the materials destruction of the dome gradually. Therefore, studying the shape and form of the dome in historic mosques can greatly assist to identify the affected points of the different types of the domes and provide solutions to prevent early destruction of the domes. In the present work, the turbulent flow of wind around the four samples of different domes is investigated, using ANSYS CFX software, to determine which parts of the dome geometry are most affected by wind and erosion. In the present work, for the first time, it will be tried to study different types of domes used in different climates and their geometric shapes, besides conducting research to prevent early erosion. The results demonstrated that a large vortex has shaped on the opposite side of the wind, which affects the area behind the dome and causes a negative pressure through velocity reduction. Also, the highest wind velocity is formed a little higher and hinder of the dome. The results of the shear stress on the crown of the dome for the four cases illustrated that for the dome type W4, the highest shear stress is about 15Pa on the face against the wind and it is about 12 Pa for that of W1 on the face opposite the wind. It should be noted that the position of the most stresses on the dome crown corresponding to the most damage to the building is estimated. Manuscript profile
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  2 - The feasibility of using solar heating in the Yazd hospital: A case study
  Mahshid Babaei Mehdi Jahangiri Farhad Raeiszadeh Gholam Reza Aboutalebi Abbas Jafari Arya Nariman
  20.1001.1.27834441.2023.15.2.2.1
  The most widespread use of solar energy as an alternative to fossil fuels is for heating. Considering the location of Iran and its location on the global Sunbelt, the aim of the present work is to provide part of the heat needed for the treatment space of Seyed Al-Shohd More

  The most widespread use of solar energy as an alternative to fossil fuels is for heating. Considering the location of Iran and its location on the global Sunbelt, the aim of the present work is to provide part of the heat needed for the treatment space of Seyed Al-Shohda hospital in Yazd by using a flat plate solar collectors system. A one-year dynamic simulation has been performed using TSOL Pro 5.5 software, and energy-environmental-economic (3E) analyzes have been performed on the proposed system. The difference between the present work and the past works is that the provision of space heating and sanitary spa needed for a treatment space has not been done yet. The results of the investigations showed that about 2MWh of solar heat is produced, which prevents the annual release of about 630kg of CO2 pollutants. Examining the system loss diagram also shows that the bottleneck of energy loss in the system under review is the hot water storage tanks, which have an annual energy loss of about 800 kWh. Financial analysis showed that the price of each kWh of solar heat production and the internal rate of return (IRR) are 0.0021 euros and 2.23%, respectively. The results of the present work indicate the excellent potential of Yazd in the field of using solar water heaters (SWH) for heating treatment spaces. The results of the present work can be used as a roadmap to help energy decision-makers and investors in this sector and accelerate the development of SWHs. Manuscript profile
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  3 - Numerical simulation of piston with different materials for justification of its strength
  Bharosh Kumar Yadav Babin Dangal Shiva Shanker Pandey Mehdi Jahangiri
  20.1001.1.27834441.2022.14.4.6.2
  This project deals with the determination of best material among the three selected ones. Initially, based on systematic literature review, three materials, i.e. aluminium 4032, grey cast iron and titanium 6Al-6V, were selected, and their properties were determined. The More

  This project deals with the determination of best material among the three selected ones. Initially, based on systematic literature review, three materials, i.e. aluminium 4032, grey cast iron and titanium 6Al-6V, were selected, and their properties were determined. Then, design specifications form YAMAHA FZV3 was taken, and required design parameters and necessary dimensions of the piston were calculated. After this, the piston's Design was performed using SOLIDWORKS 2016, followed by structural and thermal analysis using ANSYS 16.0. Finally, the results were compared and it was noticed that among three materials the highest deformation was seen for aluminum which was 31.77% more than titanium alloy while the maximum difference in stress was for grey cast iron with 39.7% more than titanium alloy. Also, the heat flux for titanium alloy was least. This indicated that titanium 6Ai-4V gave better for durability and structural and theoretical performance. Hence, it was concluded to be the best material among the selected ones for the piston used. Manuscript profile
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  4 - Estimation and mapping of the global component of solar radiation and wind power density over Chad
  Marcel Hamda Soulouknga Iman Pishkar Dieudonné Kaoga Kidmo Mehdi Jahangiri
  20.1001.1.27834441.2023.15.1.4.1
  Despite its very good potential of Chad in the field of wind and solar energy, very few studies have been conducted in the field of evaluation and estimation of these energies. Therefore, in order to develop the exploitation of these resources, for the first time, findi More

  Despite its very good potential of Chad in the field of wind and solar energy, very few studies have been conducted in the field of evaluation and estimation of these energies. Therefore, in order to develop the exploitation of these resources, for the first time, finding suitable places for the construction of wind and solar power plants has been done to help the decision-makers in the field of energy in Chad. The purpose of this work is to establish a solar map and the wind map of Chad using the geographic information system(GIS). ArcMap software was used to draw GIS maps, and determining the amount of radiation and wind speed in the neighboring points of the investigated stations was done using the Inverse Distance Weighted(IDW) method. Weibull distribution function was used to estimate wind power density and three analytical methods were used to estimate solar radiation. By comparing the different values of solar radiation, the lowest value was in N'Djamena (5.74kWh/m2/day) and the highest in Abeche (6.35kWh/m2/day). It turns out that the windiest site is Faya-Largeau located in the Saharan area with a value of 28.61W/m2. However, in the Sahelian zone, the wind density of Bokoro is the lowest at 3.16W/m2. Based on the results, the resource maps showing the wind power densities and solar irradiation over the entire regions of Chad were developed. Thus, the exploitation of solar energy seems favorable to meet the deficit in energy needs, and the use of technology namely wind turbines is desirable. Manuscript profile
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  5 - Techno-enviro assessment and dynamic energy balance simulation of the domestic-scale solar heating system in Lebanon
  Mehdi Jahangiri Hasan Ali  Lotfi Nagafabadi Esmaeil  Moradi Seyed Mohammad  Noorbakhsh Hamed  Saghaei Hussein A.  Kazem Miqdam Tariq  Chaichan
  Statistics show that the residential and service sectors consume a large amount of the total generated energy in every country, most of which is spent for space and water heating. Solar water heater (SWH) as a recently developed technique can be used for supplying most More

  Statistics show that the residential and service sectors consume a large amount of the total generated energy in every country, most of which is spent for space and water heating. Solar water heater (SWH) as a recently developed technique can be used for supplying most of the energy consumption which is necessary to be considered for social and economic development and continuously improving the quality of life. Practical measures of SWH for space and water heating have not been developed enough and no feasibility study has been conducted on the subject in Lebanon. To do so, using the energy software such METEOSYN and TSOL as very important pre-fabrication tools for the simulation, modelling and analysis of every management applications for energy development-based systems, we study the potential of using domestic-scale SWHs in residential apartments at 2 stations in Lebanon. The results show that Tripoli station, which supplies 37.8% of its total heating needs, is more suitable than Riyaq, which could provide for 32.1% of its total needs. The results also demonstrate that both stations produce 2915.7 kWh for space heating and 5403.7 kWh for water heating annually using SWH. This method prevent the emission of 2.4 tons of CO2 pollutant gas annually based on fossil fuels. Manuscript profile