Scholarlink

<p>R134a is widely used as a refrigerant in current bus air conditioning systems. Due to regulatory restrictions on the use of R134a, research into alternative refrigerants with low global warming potential (GWP) is also intensively underway. In this study, the performance of refrigerants with low-GWP that can replace R134a in bus air conditioning was analyzed using MATLAB/Simulink and Simscape environments. The model in the Simulink environment for the bus air conditioning system was designed considering real operating conditions. The initial cabin temperature was determined as 46&#xa0;°C based on experimental results, and the target cabin temperature was taken as 25&#xa0;°C. The results show that the maximum cooling capacities of the simulated refrigerants range from 15.5 to 17&#xa0;kW. Among the refrigerants that can potentially replace R134a, R516A, which has a cooling profile almost similar to R134a, stands out as the best option. R1234yf is considered the next best option due to its high performance and environmental sustainability. Although R515B provides the greatest efficiency improvement with a COP of more than 20% compared to R134a, it fails to reach the required cabin temperature of 25&#xa0;°C during the simulation period. The findings show that simply increasing the compressor speed is insufficient for R515B to achieve the required thermal comfort standards in existing bus HVAC systems. Consequently, it can be said that R516A is the most suitable refrigerant that can be used as an alternative to R134a by simply adjusting the air conditioner's compressor speed, without making extensive changes to existing bus air conditioning systems.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Dynamic modeling and comparative performance analysis of a Bus HVAC system using alternative refrigerants to R134a in MATLAB/Simulink

  • 期刊论文

  • 发表日期：

    2026年7月7日

查看全文
  • Şaban Ünal,
  • Ertuğrul Cihan

摘要

R134a is widely used as a refrigerant in current bus air conditioning systems. Due to regulatory restrictions on the use of R134a, research into alternative refrigerants with low global warming potential (GWP) is also intensively underway. In this study, the performance of refrigerants with low-GWP that can replace R134a in bus air conditioning was analyzed using MATLAB/Simulink and Simscape environments. The model in the Simulink environment for the bus air conditioning system was designed considering real operating conditions. The initial cabin temperature was determined as 46 °C based on experimental results, and the target cabin temperature was taken as 25 °C. The results show that the maximum cooling capacities of the simulated refrigerants range from 15.5 to 17 kW. Among the refrigerants that can potentially replace R134a, R516A, which has a cooling profile almost similar to R134a, stands out as the best option. R1234yf is considered the next best option due to its high performance and environmental sustainability. Although R515B provides the greatest efficiency improvement with a COP of more than 20% compared to R134a, it fails to reach the required cabin temperature of 25 °C during the simulation period. The findings show that simply increasing the compressor speed is insufficient for R515B to achieve the required thermal comfort standards in existing bus HVAC systems. Consequently, it can be said that R516A is the most suitable refrigerant that can be used as an alternative to R134a by simply adjusting the air conditioner's compressor speed, without making extensive changes to existing bus air conditioning systems.