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Journals / Afyon Kocatepe Üniversitesi Fen ve Mühendislik Bilimleri Dergisi / 2026 / Cilt: 26 Sayı: 3

Performance Analysis of Single-Stage and Vapor Injection Transcritical CO2 Refrigeration Cycles: Energy, Exergy, and Component-Wise Evaluation

Tek Kademe ve Buhar Enjeksiyonlu Transkritik CO2 Soğutma Çevrimlerinin Performans Analizi: Enerji, Ekserji ve Bileşen Bazlı Değerlendirme

İbrahim Karaçaylı(EGE ÜNİVERSİTESİ, BERGAMA MESLEK YÜKSEKOKULU, ELEKTRİK VE ENERJİ BÖLÜMÜ, İKLİMLENDİRME VE SOĞUTMA TEKNOLOJİSİ PR.)0000-0002-4459-1450
Pages
790–801
Publication Date
2026-06-03
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Overall, the results demonstrate that the vapor injection transcritical CO₂ cycle provides improved energy and exergy performance while maintaining considerable potential for waste heat utilization.

📌 3 Key Takeaways

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Objective & Hypothesis:This study investigates the energy and exergy performance of single-stage and vapor injection transcritical CO₂ refrigeration cycles under different operating conditions.
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Key Findings & Data:The analysis includes low and moderate evaporation temperatures and various gas cooler pressures.
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Conclusion & Impact:Overall, the results demonstrate that the vapor injection transcritical CO₂ cycle provides improved energy and exergy performance while maintaining considerable potential for waste heat utilization.
🔬Design:Araştırma Makalesi
📍Scope:Comprehensive Sample
⚙️Variables:Transkritik CO2 soğutma · Buhar enjeksiyonlu çevrim · Enerji ve ekserji analizi

Abstract

This study investigates the energy and exergy performance of single-stage and vapor injection transcritical CO₂ refrigeration cycles under different operating conditions. The analysis includes low and moderate evaporation temperatures and various gas cooler pressures. The vapor injection cycle consistently shows lower compressor power consumption and reduced total exergy destruction compared to the single-stage cycle. At low evaporation temperatures, the compressor power and total exergy destruction decrease by about 32% and 46%, respectively. At moderate temperatures, the vapor injection cycle also achieves higher COP and exergy efficiency, increasing by 13.1% and 11.0% at the optimum gas cooler pressure. Although the heat rejected from the gas cooler and its thermal exergy slightly decrease, the reduction is small compared to the gains in system performance. Component-wise analysis shows that the throttle valve is the main source of irreversibility in both cycles, and its absolute exergy destruction is reduced significantly with vapor injection. Overall, the results demonstrate that the vapor injection transcritical CO₂ cycle provides improved energy and exergy performance while maintaining considerable potential for waste heat utilization.

Özet

Bu çalışma, farklı çalışma koşulları altında tek kademe ve buhar enjeksiyonlu transkritik CO₂ soğutma çevrimlerinin enerji ve ekserji performansını incelemektedir. Analiz, düşük ve orta seviyedeki buharlaşma sıcaklıklarını ve farklı gaz soğutucu basınçlarını kapsamaktadır. Buhar enjeksiyonlu çevrim, tek kademe çevrime kıyasla sürekli olarak daha düşük kompresör güç tüketimi ve toplam ekserji yıkımı göstermektedir. Düşük buharlaşma sıcaklıklarında kompresör gücü ve toplam ekserji yıkımı sırasıyla yaklaşık %32 ve %46 oranında azalır. Orta sıcaklıklarda ise buhar enjeksiyonlu çevrim, optimum gaz soğutucu basıncında COP ve ekserji verimliliğini sırasıyla %13,1 ve %11 oranında artırmaktadır. Gaz soğutucudan atılan ısı ve termal ekserji biraz azalsa da bu azalma sistem performansındaki kazançlarla kıyaslandığında önemsizdir. Bileşen bazlı analiz, her iki çevrimde de en büyük tersinmezlik kaynağının genleşme vanası olduğunu ve buhar enjeksiyonu ile valfin mutlak ekserji yıkımının önemli ölçüde azaldığını göstermektedir. Genel olarak, bulgular buhar enjeksiyonlu transkritik CO₂ çevriminin enerji ve ekserji performansını artırdığını ve gaz soğutucudan atılan ısının geri kazanımı için önemli bir potansiyel sunduğunu göstermektedir.

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Cite This Article

Karaçaylı, İ. (2026). Performance Analysis of Single-Stage and Vapor Injection Transcritical CO2 Refrigeration Cycles: Energy, Exergy, and Component-Wise Evaluation. Afyon Kocatepe Üniversitesi Fen ve Mühendislik Bilimleri Dergisi, Cilt: 26 Sayı: 3, 790–801. https://doi.org/10.35414/akufemubid.1878224

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