Analysis of the mixing of hydrogen (g) in the refrigerant (R314a) on the cooling engine performance

Synthetic refrigerants are not environmentally friendly as they can cause damage to the ozone layer, depending on the value of ozone depletion potential (ODP) and global warming potential (GWP). Synthetic refrigerants commonly used are HCFCs that have relatively high ODP and GWP. Therefore, it is necessary to conduct research to find alternative refrigerants that are environmentally friendly. This research uses hydrogen compounds as an alternative refrigerant. To maintain safety in research, flammable hydrogen compounds are not 100% used. Therefore, hydrogen compounds are mixed with refrigerant R134a. This study aims to determine the effect of a mixture of hydrogen with R134a on the performance of the cooling engine by using experimental methods. The parameters obtained from the measuring instrument are used for calculating the cooling rate, COP, and EER. The research results show that adding more hydrogen can affect the COP and EER values due to several factors: the density of the mixture, the pressure of the fluid in the compressor, and electrical energy. The more hydrogen mixture, the smaller the density so that the fluid pressure inside the compressor is lower. The lower the fluid pressure in the compressor, the lighter the compressor performance so that the energy required is getting smaller. This causes COP and EER to be higher in a mixture of 45% hydrogen and 55% R134a refrigerant. It is also necessary to pay attention to the safety level of using hydrogen in the cooling system, adding several safety devices to detect leaks in the cooling system and shutting off fluid movement if the process temperature exceeds the flame temperature of the hydrogen compound.