dubi̇ted Duzce University Journal of Science and Technology 2148-2446 Duzce University 10.29130/dubited.1702319 Mechanical Engineering (Other) Makine Mühendisliği (Diğer) Transkritik Bir Isı Pompasının Performansının IoT Sistem ile İzlenmesi Monitoring the Performance of a Transcritical Heat Pump Using an IoT System https://orcid.org/0000-0001-6382-5462 Özgür Arif Emre ISPARTA UYGULAMALI BİLİMLER ÜNİVERSİTESİ https://orcid.org/0000-0002-8168-9668 Deniz Özdemir ISPARTA UYGULAMALI BİLİMLER ÜNİVERSİTESİ https://orcid.org/0009-0003-0217-9200 Gül Ümit Murat 04 19 2026 14 2 594 604 05 22 2025 03 09 2026 Copyright © 2013, Duzce University Journal of Science and Technology 2013 Duzce University Journal of Science and Technology

Artan enerji ihtiyacı ve çevresel kaygılar, enerji verimliliği yüksek ve çevre dostu teknolojilere olan yönelimi artırmıştır. Bu bağlamda, doğal soğutkan R744 (CO₂) kullanan transkritik ısı pompaları öne çıkmaktadır. Ancak bu sistemlerin optimum performansta çalıştırılması ve yönetilmesi için gerçek zamanlı izleme kritik öneme sahiptir. Bu çalışma, bir transkritik CO₂ ısı pompasının performansını Nesnelerin İnterneti (IoT) teknolojileri kullanarak izlemek ve analiz etmek amacıyla özgün bir sistem geliştirmeyi hedeflemiştir. Sistem, Raspberry Pi ve Arduino mikrodenetleyicileri, çeşitli sensörler (sıcaklık, basınç, akış, güç), MySQL veritabanı ve çift arayüz (Lazarus tabanlı yerel ve PHP/JavaScript/HTML tabanlı web) üzerine kurulmuştur. Arduino sensör verilerini toplayıp C dili ile işlerken, Raspberry Pi üzerinde Lazarus ile geliştirilen nesne yönelimli yazılım verileri almış, işlemiş, depolamış ve yerel arayüzde sunmuştur. Eş zamanlı olarak web arayüzü, verilere uzaktan erişim ve görselleştirme imkânı sağlamıştır. Geliştirilen sistem, ısı pompasının kritik performans parametrelerinin (sıcaklık, basınç, akış, güç tüketimi, COP hesaplaması için gerekli veriler) başarılı bir şekilde izlenmesini sağlamıştır. Sonuçlar, önerilen IoT tabanlı izleme sisteminin transkritik ısı pompalarının enerji verimliliğini artırma, operasyonel yönetimi kolaylaştırma ve potansiyel arızaları erken tespit etme potansiyeline sahip olduğunu göstermektedir.

The growing energy demand and environmental concerns have increased the orientation towards energy- efficient and environmentally friendly technologies. In this context, transcritical heat pumps using natural refrigerant R744 (CO₂) stand out. However, real-time monitoring is critical for operating and managing these systems at optimum performance. This study aimed to develop a unique system to monitor and analyze the performance of a transcritical CO₂ heat pump using Internet of Things (IoT) technologies. The system is based on Raspberry Pi and Arduino microcontrollers, various sensors (temperature, pressure, flow, power), a MySQL database, and a dual interface (Lazarus-based local and PHP/JavaScript/HTML-based web). While Arduino collected and processed sensor data using C language, the object-oriented software developed with Lazarus on Raspberry Pi received, processed, stored the data, and presented it on the local interface. Simultaneously, the web interface provided remote access and visualization of the data. The developed system successfully monitored the critical performance parameters of the heat pump (temperature, pressure, flow, power consumption, data required for COP calculation). The results indicate that the proposed IoT-based monitoring system has the potential to increase the energy efficiency of transcritical heat pumps, facilitate operational management, and enable early detection of potential failures.

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