تاثير اصلاح نشت و افزايش دبي آب خنك كننده كندانسور بر عملكرد سيستم آب شيرين‌كن خورشيدي بر پايه خلأ طبيعي و مجهز به كلكتور لوله خلأ

Effect of Leakage Modification and Cooling Flow Rate Increase of Water-Cooled Condenser on NVD System Performance Equipped with Vacuum Tube Collectors

زﻣﯿﻨﻪ و ﻫﺪف: ﻋﺪم دﺳﺘﺮﺳﯽ ﺑﻪ آب ﺷﯿﺮﯾﻦ ﮐﺎﻓﯽ، از ﻣﺸﮑﻼت ﺗﻬﺪﯾﺪ ﮐﻨﻨﺪه ﻣﺮدم ﺳﺮاﺳﺮ ﺟﻬﺎن ﻣﯽ ﺑﺎﺷﺪ و ﺑﺮاي ﺟﻠﻮﮔﯿﺮي از وﻗﻮع اﯾﻦ ﻣﺸﮑﻼت، ﺗﺤﻘﯿﻘﺎت زﯾﺎدي ﺑﻪ ﻣﻨﻈﻮر ﯾﺎﻓﺘﻦ روش ﻫﺎﯾﯽ ﺟﺪﯾﺪ ﺑﺮاي ﺧﺎﻟﺺ ﺳﺎزي ﻣﻨﺎﺑﻊ ﻣﺨﺘﻠﻒ آب ﺷﻮر ﺑﺎ ﻫﺰﯾﻨﻪ، اﻧﺮژي و ﺗﺎﺛﯿﺮات ﻣﺤﯿﻂ زﯾﺴﺘﯽ ﮐﻤﺘﺮ، در ﺣﺎل اﻧﺠﺎم ﻣﯽ ﺑﺎﺷﺪ. اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺑﺎ ﻫﺪف ﺗﻮﻟﯿﺪ آب ﺷﯿﺮﯾﻦ ﺑﻪ روش ﺧﻸ ﻃﺒﯿﻌﯽ و ﺑﺎ اﺳﺘﻔﺎده از ﻟﻮﻟﻪ ﻫﺎي ﺧﻸ و اﯾﺠﺎد ﺧﻸ ﺗﻮﺳﻂ ﭘﻤﭗ ﺧﻸ ﺻﻮرت ﮔﺮﻓﺘﻪ اﺳﺖ ﮐﻪ ﺑﻪ ﻋﻨﻮان ﺗﻠﻔﯿﻘﯽ ﻧﻮآوراﻧﻪ ﻣﺤﺴﻮب ﻣﯽ ﺷﻮد. ﻣﻀﺎﻓﺎ ﺗﺎﺛﯿﺮ ﻓﺸﺎرﻫﺎي ﻣﺨﺘﻠﻒ ﺧﻸ ﺑﺮ روي ﻣﯿﺰان آب ﺷﯿﺮﯾﻦ ﺗﻮﻟﯿﺪي و ﺳﭙﺲ ﺗﺎﺛﯿﺮ اﺻﻼح ﻧﺸﺖ و اﻓﺰاﯾﺶ دﺑﯽ آب ﺧﻨﮏ ﮐﻨﻨﺪه ﮐﻨﺪاﻧﺴﻮر ﺑﺮ ﻋﻤﻠﮑﺮد ﺳﯿﺴﺘﻢ ﺑﻪ ﺻﻮرت ﺗﺠﺮﺑﯽ ﺑﺮرﺳﯽ ﺷﺪه اﺳﺖ. روش ﺑﺮرﺳﯽ: در اﯾﻦ ﺗﺤﻘﯿﻖ، از ﭘﻤﭗ ﺧﻸ ﺟﻬﺖ اﯾﺠﺎد ﺧﻸ اوﻟﯿﻪ اﺳﺘﻔﺎده ﺷﺪه و ﺑﺎ ﺧﺎﻣﻮش ﺷﺪن آن، ﺳﺘﻮن ﺑﺎروﻣﺘﺮﯾﮏ آب ﺑﻪ ﻃﻮر ﻃﺒﯿﻌﯽ ﻧﻘﺶ ﺣﻔﻆ ﺧﻸ در روزﻫﺎي ﻣﺘﻮاﻟﯽ ﺑﻌﺪ را دارد. از ﮐﻠﮑﺘﻮرﻫﺎي ﻟﻮﻟﻪ ﺧﻸ ﺑﺮاي ﺑﺎﻻ ﺑﺮدن ﻧﺮخ اﻧﺘﻘﺎل ﺣﺮارت ﺑﻪ آب ﺷﻮر اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﺳﭙﺲ ﻋﻤﻠﮑﺮد ﺳﯿﺴﺘﻢ در روزﻫﺎي ﻣﺘﻮاﻟﯽ ﻣﻮرد ﺗﺤﻘﯿﻖ ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. ﭘﺲ ازاﺻﻼﺣﺎت اﻧﺠﺎم ﯾﺎﻓﺘﻪ در ﺳﯿﺴﺘﻢ، ﻣﯿﺰان آب ﺗﻮﻟﯿﺪي و راﻧﺪﻣﺎن ﺳﯿﺴﺘﻢ ﻣﻮرد ﺗﺤﻠﯿﻞ و ﻣﻘﺎﯾﺴﻪ ﻗﺮار ﮔﺮﻓﺘﻪ اﻧﺪ. از ﭘﯿﺮاﻧﻮﻣﺘﺮ، ﻓﺸﺎر ﺳﻨﺞ ﺧﻸ و ﺗﺮﻣﻮﮐﻮﭘﻞ ﻧﯿﺰ ﺑﻪ ﺗﺮﺗﯿﺐ ﺟﻬﺖ اﻧﺪازه ﮔﯿﺮي ﺷﺪت ﺗﺎﺑﺶ، ﻓﺸﺎر ﺳﯿﺴﺘﻢ و دﻣﺎي ﻧﻘﺎط ﻣﺨﺘﻠﻒ ﺳﯿﺴﺘﻢ اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﯾﺎﻓﺘﻪﻫﺎ: در اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﺑﺎ اﻓﺰاﯾﺶ ﻓﺸﺎر ﺧﻸ ﻣﯿﺰان آب ﺗﻮﻟﯿﺪي ﺳﯿﺴﺘﻢ و راﻧﺪﻣﺎن اﻓﺰاﯾﺶ ﯾﺎﻓﺘﻪ و ﺑﺎ اﻧﺠﺎم اﺻﻼح ﻧﺸﺖ و اﻓﺰاﯾﺶ دﺑﯽ آب ﺧﻨﮏ ﮐﻨﻨﺪه ﮐﻨﺪاﻧﺴﻮر، راﻧﺪﻣﺎن ﺳﯿﺴﺘﻢ ﺗﻐﯿﯿﺮ اﻧﺪﮐﯽ داﺷﺘﻪ اﺳﺖ ﺑﻪ ﻃﻮري ﮐﻪ ﺳﯿﺴﺘﻢ ﻣﯽ ﺗﻮاﻧﺪ در ﺗﻌﺪاد روزﻫﺎي ﻣﺘﻮاﻟﯽ و ﻣﺘﻌﺪد ﺑﺪون اﯾﺠﺎد ﺧﻸ ﻣﺠﺪد، آب ﺗﻮﻟﯿﺪ ﮐﻨﺪ. ﺑﺤﺚ و ﻧﺘﯿﺠﻪﮔﯿﺮي: ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ از آزﻣﺎﯾﺶ ﻫﺎ ﻧﺸﺎن ﻣﯽ دﻫﺪ ﮐﻪ ﺑﺎ اﻓﺰاﯾﺶ ﺧﻸ ﻣﯿﺰان ﺗﻮﻟﯿﺪ آب ﺷﯿﺮﯾﻦ و راﻧﺪﻣﺎن ﺳﯿﺴﺘﻢ اﻓﺰاﯾﺶ ﻣﯽ ﯾﺎﺑﺪ. ﻫﻤﭽﻨﯿﻦ ﭘﺲ از اﻧﺠﺎم ﺗﻐﯿﯿﺮات در ﺳﯿﺴﺘﻢ ، ﺑﻪ ﻣﯿﺰان kg/m2d 8/114 آب ﺗﻮﻟﯿﺪ ﺷﺪه اﺳﺖ. ﻣﻀﺎﻓﺎ راﻧﺪﻣﺎن ﺑﻪ ﺑﺎﻻي 51 درﺻﺪ رﺳﯿﺪه و ﻧﯿﺰ ﺗﻐﯿﯿﺮ ﺟﺰﺋﯽ در روزﻫﺎي ﻣﺘﻮاﻟﯽ اوﻟﯿﻪ داﺷﺘﻪ ﮐﻪ در ﻧﺘﯿﺠﻪ آن ﺳﯿﺴﺘﻢ ﻗﺎدر ﺑﻪ ﺗﻮﻟﯿﺪ آب ﺑﻪ ﺑﯿﺶ از ﺳﻪ روز ﺑﺪون اﺳﺘﻔﺎده ﻣﺠﺪد از ﭘﻤﭗ ﺧﻸ ﺷﺪه اﺳﺖ.

Background and Objective: Lack of access to sufficient fresh water is a major threat to people around the world, and to prevent this, extensive research is being done to find new ways to purify different sources of brackish water at lower cost, energy and environmental impacts. The purpose of this study is to produce the freshwater through an NVD system using vacuum tube collectors and vacuum creation by a vacuum pump. Hence, this kind of system could be considered as an innovative combination one; in addition, the effect of different vacuum pressures on yield, then the effect of leakage modification and flow rate increase of cooling water on the system performance were experimentally investigated. Method: In this research, a vacuum pump was utilized to create an initial vacuum, and when it is switched off, a barometric water column maintains the vacuum naturally throughout the consecutive days. The vacuum collectors were used in order to enhance the saline water heat transfer; later the system performance was continually examined. After the improvements were carried to the system, the yield and efficiency were analyzed and compared with the first test. Furthermore, a pressure gauge, a pyranometer and some thermocouples were applied so as to measure the system pressure, solar radiation and temperatures respectively. Findings: The current study found that the yield and efficiency of the system increased by raising the vacuum pressure; besides, after the leakage modification and cooling water flow rate enhancement, the efficiency has been insignificantly varied in the first consecutive days resulting in a superior capability to produce fresh water for more than three days without reusing the vacuum pump. Discussion and Conclusion: The results of this study indicated that raising the vacuum pressure increased the yield and efficiency so that they reached to 8.114 kg/m2d and more than 51% respectively. Moreover, the efficiency slightly varied and as a result, the system would be able to produce freshwater for more than three days without reutilizing vacuum pump.