Application of CO₂ refrigeration systems on small fishing vessels: experimental laboratory & simulation results

Seafood plays an important role in the local food supply chain, especially in coastal areas of low- and middleincome countries (LMICs). Most small fishing vessels do not have an active refrigeration system to chill the catch, and only sometimes use ice brought from shore to chill the catch. The product temperature is known to have a major influence on product quality, and its control is therefore key to limit product degradation. Therefore, it could be advantageous to implement a CO₂ refrigeration system onboard. It helps control product temperature, preserves the quality and prevent spoilage of the catch. This paper presents experimental results of a compact subcritical CO₂ refrigerated seawater system (RSW). A Modelica model was developed to simulate the CO₂ refrigeration system's performance under various operating conditions. The simulation results suggest that using a capillary tube as an expansion device is a feasible alternative to manual expansion valves. However, further validation of the model is required to ensure performance reliability.