كليدواژه :
بهينهسازي چندهدفه , تصميمسازي , مدلسازي ترموديناميكي و اقتصادي , سيستم تبريد
چكيده فارسي :
در اين پژوهش هدف ارائه راهبرد يافتن حالت بهينه يك سيستم تبريد براي يك ساختمان مسكوني در شهر تهران از ميان سه سيستم تبريد تراكمي معمولي، دوكمپرسوره و با صرفهجويي كننده با سيال عامل R-134a است. ضريب عملكرد و نياز درآمدي كل به عنوان توابع هدف در نظر گرفته شده اند و روش بهينهسازي روش الگوريتم ژنتيك دوهدفه است. فشارهاي عملكردي و نسبت دبي جرمي در صرفهجويي كننده به عنوان متغيرهاي اثرگذار انتخاب شدهاند. گزينه مناسب از جبهه پارتو با استفاده از روش تاپسيس انتخاب شده است. بيشترين ضريب عملكرد براي سيكل تبريد با صرفهجويي كننده و كمترين هزينه براي سيكل تبريد معمولي است. بهترين حالت از حالت بهينه سه سيكل تبريد با استفاده از روش تصميمسازي نوين سلسله مراتبي، معيار اقتصادي و معيار عملكرد مشخص شده است و اولويت اول، دوم و سوم به ترتيب با سيستم تبريد تراكمي معمولي، با صرفهجويي كننده و دوكمپرسوره است.
چكيده لاتين :
An air conditioning system for a sample building with an area of 97.1m2 on the
floor was considered. Three cooling systems are considered: a normal compression refrigeration system, a refrigeration system with an economizer, a
refrigeration system with two compressors. The working fluid in three systems
is R - 134 a. First, thermodynamic and economic modeling of each cycle was
done, which was followed by considering the performance coefficient as thermodynamic representative and the total income requirement as economic
representative. The functional pressures and the ratio of mass flow rate in the
economizer are chosen as decision variables. The optimization method is Multi
objective Genetic algorithm (NSGAII), and the final option is chosen using the
Analytic Hierarchy Process. The economic model takes into account the cost of
the components, including amortization and maintenance. In order to
deu{fb01}ne a cost function, which depends on the optimization parameters of
interest, component costs have to be expressed as functions of thermodynamic
variables. The noteworthy point is that the cycle costs are higher than the
other two cycles, and the compressor cycle costs are higher than the normal
refrigeration cycle. This behavior results from the higher heating of the cycle
with two compressors compared to the normal cycle. The cost of the installation
of an economizer has increased the cost of the refrigeration cycle with an economizer. In this cycle, the flow rate in the evaporator is low and, to achieve the chiller load, the heat exchanger surface is higher. The cycle performance with an economizer is more than that in two other cycles, and the cost of the cycle with two compressors is higher than that of the other two cycles. In the evaluation of options, the scale of the performance coefficient is measured by 2 to 1. Based on the observed results, the normal compression refrigeration system is chosen because it is more inexpensive than other options; then, the system with an economizer is chosen as the second option.