Numerical simulations on evaporator coils of sustainable cold storages for food chain application
The development of cold storage in Indonesia is less than satisfactory. As the second highest producers of fishery and aquaculture products in the world, the country has only 2 out of total 6 of its ocean fishing ports possess cold storage facilities. Indonesia is also on the list of low index cold storage markets with abundant natural resources. The lack of cold storage facilities has greatly restricted the development of its fishery and food industries. The current infrastructure is also too poor to exploit the resources efficiently. Under this circumstance, technologies that can encourage development of sustainable cold storages applied for food chain and related components such evaporator coils in the country is in great demand. To date there has not been much research into cold storage evaporator coil design specifically for natural refrigerants such as Hydrocarbon (HC) and CO2. This paper presents results of theoretical investigation on the main design parameters of natural refrigerant evaporator coils which can be applied in sustainable cold storage systems. The parameters included tube diameter, number of refrigerant circuits, evaporator temperature and circulation ratio. A lumped element technique was applied to develop evaporator models which were used to design and to simulate different coil geometry and circuit arrangements. The results from published papers were used for model validation. The evaporators considered were direct expansion and flooded evaporator coils for low temperature cold storage applications. The paper also presents comparison analyses of natural refrigerant (HC and CO2) evaporator coils and direct expansion coils using the synthetic refrigerant R-404A.