بررسی ترمودینامیکی- اقتصادی سیستم تبرید جریان مبرد متغیر

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی مکانیک، دانشگاه آزاد اسلامی واحد کرمان، کرمان، ایران

چکیده

تحلیل اگزرژی و ترمواکونومیک، روشی موثر جهت تعیین مشخصات ترمودینامیکی و بهینه سازی عملکرد ترمودینامیکی - اقتصادی سیستم های تبرید و تهویه مطبوع می باشد. مطالعه حاضر به تحلیل اگزرژی و ترمواکونومیک یک سیستم تبرید جریان مبرد متغیر با چهار اواپراتور که در صنایع لبنی مورد استفاده قرار می گیرد، می پردازد. از یک کد کامپیوتری که در نرم افزار EES نوشته شده، جهت شبیه سازی سیستم استفاده شده است. اثر سه مبرد R502 ، R1234ze و R134a بر پارامتر های ترمودینامیکی - اقتصادی سیستم مورد بررسی قرار گرفته است. علاوه بر محاسبه راندمان اگزرژی چرخه تبرید برای سه مبرد فوق، اثر دمای تبخیر و تقطیر بر مقدار تخریب اگزرژی و راندمان اگزرژی سیستم مورد بررسی قرار گرفته است. نتایج نشان می دهند که مقدار تخریب اگزرژی در کمپرسور، از 3/947 کیلو وات برای مبرد R134a تا 4/221 کیلو وات برای مبرد R502 به میزان 7% افزایش یافته است. میزان تخریب اگزرژی در چگالنده در رده دوم برای همه مبرد ها محاسبه شده است. در تحلیل ترمواکونومیک مشاهده گردید کمترین میزان هزینه به میزان 73794 دلار مربوط به مبرد R502 است و هزینه سالیانه کل سیستم برای مبردهای R1234ze و R134a در رده های بعدی قرار دارند.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Thermoeconomic Analysis of a Variable Refrigerant Flow System

نویسندگان [English]

  • Ramin Zahiri
  • Mohammad Mehdi Keshtkar
Mechanical Eng. Department, Islamic Azad University, Kerman, Iran
چکیده [English]

Exergy and thermoeconomic analysis is an effective method for determining thermodynamic characteristics and optimizing thermodynamic-economic performance of refrigeration systems. The present study deals with exergy and thermoeconomic analysis of a variable refrigerant flow system with four evaporators used in the dairy industry. A computer code written in EEs software was used for system simulation. Impact of three refrigerants, R502, R1234ze and R134a, on thermodynamic-economic parameters of the system was investigated. In addition to calculation of exergy efficiency of refrigeration cycle for three mentioned refrigerants, effect of evaporation and distillation temperature on system exergy degradation and exergy efficiency of was also investigated. Results showed that R1234ze gas can be appropriate alternative for R502 and R134a gases. Results show that exergy destruction in compressor in reference temperature from 3.974kW for R134a refrigerant increases to 4.221 kW for refrigerant R502. Exergy destruction in the condenser in second level was calculated for all refrigerants. In thermoeconomic analysis, costs of components of variable refrigerant flow system were investigated and total costs for R134a-R502-R1234ze refrigerants were studied. It was observed that a lowest cost is related to R502 refrigerant and total annual cost for or R134a and R1234ze refrigerants are in the next ranks.

کلیدواژه‌ها [English]

  • Exergy analysis
  • thermoeconomic analysis
  • variable refrigerant flow
  • refrigeration system
  • exergy degradation

مراجع

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نشریه مهندسی مکانیک امیرکبیر
دوره 51، شماره 4
مهر و آبان 1398
صفحه 1-10

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