مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بررسی تجربی تاثیر تغییر دمای محیط بر عملکرد یخچال پرده هوای عمودی

نوع مقاله : پژوهشی اصیل

نویسندگان
الهام اسکندری 1
ابراهیم حاجی دولو 1
محمدرضا صفاریان 1
سعید محقق 2
امید ادیبی 2
1 دانشگاه شهید چمران اهواز
2 پژوهشگاه نیرو
10.48311/mme.24.9.583
چکیده
استفاده از یخچال‌‌های ‌پرده‌هوای عمودی در فروشگاه‌‌های مواد غذایی با استقبال روبرو شده است، زیرا زمینه دسترسی آسان مشتریان به محصولات را فراهم می‌سازد. علیرغم جذابیت‌ یخچال‌‌های ‌پرده‌هوا، مصرف انرژی این یخچال‌‌‌ها حدود 50% بیشتر از یخچال‌‌های درب‌دار می‌باشد. در این مقاله تاثیر تغییر دمای محیط بر عملکرد یخچال بصورت تجربی مورد بررسی قرار گرفته شده است. اندازه گیری تجربی شامل پارامترهای دما، فشار، رطوبت نسبی، سرعت و جریان مصرفی در سیکل هوا و سیکل تبرید می‌باشد. همچنین توان کمپرسور، اثر تبرید، بار کل یخچال، ضریب عملکرد، نسبت فشار، ضریب نفوذ حرارتی، توان تبرید، دبی حجمی و جرمی هوای فن اواپراتور و کندانسور، دبی جرمی مبرد، حرارت کندانسور، توان کندانسور، راندمان حرارتی پرده‌هوا، عدد ریچاردسون، عدد رینولدز و مدول انحراف در شرایط مختلف محیطی محاسبه گردید. نتایج تجربی نشان می دهد که عملکرد برودتی یخچال تحت تاثیر دمای هوای محیط کارکرد بوده که مستقیما بر نرخ نفوذ هوای محیط به محفظه یخچال و دمای هوای برگشتی به اواپراتور تاثیر می‌گذارد. لذا دمای هوای برگشتی به اواپراتور شاخص مهمی برای ارزیابی میزان کارآیی یخچال ‌پرده‌ هوا می باشد. هرچه دمای محیط افزایش توان مصرفی کمپرسور افزایش، اثر تبرید و ضریب عملکرد یخچال کاهش می‌یابند. همچنین نتایج نشان می‌دهد که با افزایش دمای محیط راندمان پرده هوا کاهش می‌یابد بطوریکه تفاوت دمای جلو و عقب طبقات تا 6/4 درجه سلسیوس رسیده و با افزایش هر درجه دمای محیط به‌طور تقریبی توان مصرفی کمپرسور به مقدار 64/0% افزایش یافته و اثر تبرید و 06/0% ضریب عملکرد 77/1 % کاهش می‌یابد.
کلیدواژه‌ها
یخچال ‌پرده‌هوا
بررسی تجربی
مصرف انرژی
ضریب عملکرد

موضوعات

عنوان مقاله English

An experimental investigation on the effect of ambient temperature on the performance of a vertical air curtain refrigerator

نویسندگان English

Elham Eskandari 1
Ebrahim Hajidavalloo 1
Mohammad Reza Saffarian 1
Saeed Mohaghegh 2
Omid Adibi 2
1 Shahid Chamran University of Ahvaz
2 Niroo research center
چکیده English

Application of vertical air curtain refrigerators in commercial stores has gained popularity due to easy access of products by the customers. However, energy consumption of these refrigerators is approximately %50 higher than that of refrigerators with doors. This paper experimentally investigates the effect of ambient temperature variation on the performance of these refrigerators. Experimental measurements include parameters such as temperature, pressure, relative humidity, velocity, and power consumption in both air cycle and refrigeration cycle. Moreover, parameters such as compressor power, refrigeration effect, total load, coefficient of performance, pressure ratio, thermal entrainment coefficient, refrigeration capacity, volumetric and mass flow rates of air in the evaporator and condenser, refrigerant mass flow rate, condenser heat, air curtain thermal efficiency, Richardson number, Reynolds number, and deviation modulus under different ambient conditions were calculated. The experimental results show that the refrigeration performance is affected by ambient air temperature, which directly influence on the infiltration rate of ambient air into the refrigerator compartment and on the return air temperature to the evaporator. Therefore, the return air temperature is crucial indicator for assessing the efficiency of the refrigerator. With increasing ambient temperature, compressor power increases, while the refrigeration effect and COP decrease. The results also indicate that as ambient temperature rises, air curtain efficiency decreases somehow that temperature difference between front and rear of the shelves may reach up to 4.6°C. For every 1°C increase in ambient temperature, compressor power consumption increases by approximately %0.64, while refrigeration effect and COP decrease by %0.06 and %1.77, respectively

کلیدواژه‌ها English

Air-Curtain Refrigerator
Experimental Stud
energy consumption
coefficient of performance
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مهندسی مکانیک مدرس
دوره 24، شماره 9
شهریور 1403
صفحه 583-595