Innovative Proposals for Defogging Design Criteria of Refrigerated Display Cabinets

Abstract

Fogging on glass surfaces in refrigerated display cabinets (RDCs) significantly impacts product visibility, energy consumption, air curtain stability, product temperature uniformity, and, indirectly, food safety. Traditionally used, continuously operating anti-sweat heaters and anti-fog coatings require more sustainable solutions due to high operating costs and long-term performance decline. This study investigates the effects of airflow structure, structural design, advanced material properties, and control strategies on fog formation, and proposes design-oriented approaches to prevent fog formation during its development phase. In addition to structural improvements such as composite profiles that reduce thermal bridges, hydrophobic materials, Low-E coating glass, and argon-filled multi-pane glass units, this study proposes optimizing discharge air grille angles to increase air curtain stability, panel perforation strategies based on loading scenarios, and environmentally sensitive control algorithms. The proposed approaches aim to improve energy efficiency while maintaining food safety and ensuring sustainable operational performance. It can be estimated that implementing these proposals will result in energy savings of 5-10%.

Keywords

• Refrigerated display cabinet
• refrigeration
• defogging
• energy efficiency

Teşhir Tipi Soğutucuların Buğu Giderme Tasarım Kriterleri İçin Yenilikçi Öneriler

Öz

Teşhir tipi soğutucularda cam yüzeylerde oluşan buğulanma, ürün görünürlüğünü, enerji tüketimini, hava perdesinin istikrarını, ürün sıcaklığının homojenliğini ve dolaylı olarak gıda güvenliğini önemli ölçüde etkiler. Geleneksel olarak kullanılan, sürekli çalışan buğu önleyici ısıtıcılar ve buğu önleyici kaplamalar, yüksek işletme maliyetleri ve uzun vadeli performans düşüşü nedeniyle daha sürdürülebilir çözümler gerektirmektedir. Bu çalışma, hava akışı yapısı, yapısal tasarım, gelişmiş malzeme özellikleri ve kontrol stratejilerinin buğu oluşumu üzerindeki etkilerini araştırmakta ve geliştirme aşamasında buğu oluşumunu önlemek için tasarım odaklı yaklaşımlar önermektedir. Isı köprülerini azaltan kompozit profiller, hidrofobik malzemeler, Low-E kaplamalı cam ve argon dolgulu çok camlı cam üniteleri gibi yapısal iyileştirmelerin yanı sıra, bu çalışma hava perdesinin stabilitesini artırmak için hava üfleme ızgarası açılarının optimize edilmesini, yükleme senaryolarına dayalı panel delme stratejilerini ve çevreye duyarlı kontrol algoritmalarını önermektedir. Önerilen yaklaşımlar, gıda güvenliğini korurken ve sürdürülebilir operasyonel performansı garanti ederken enerji verimliliğini artırmayı amaçlamaktadır. Bu önerilerin uygulanmasının %5-10 oranında enerji tasarrufu sağlayacağı tahmin edilebilir.

Anahtar Kelimeler

• Teşhir tipi soğutucu
• soğutma
• buğu giderme
• enerji verimliliği

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