The working principle of a spiral heat exchanger is based on the counter-current flow principle. The two fluids flow in opposite directions through the spiral channels, with the hot fluid flowing through one channel and the cold fluid flowing through the other channel.
The two fluids are separated by a thin metal sheet, which allows for efficient heat transfer between the two fluids. This type of heat exchanger consists of concentric shape flow passages which help in creating a turbulent flow of a fluid which in turn increases the heat transfer efficiency.
Initial installation cost is higher but highly efficient as compared to other types as space-saving is much more because of the compact size. The spiral design of the heat exchanger channels allows for a compact and efficient design, with a high heat transfer coefficient.
The large surface area of the channels and the counter-current flow principle of the two fluids allows for efficient heat transfer, even when dealing with fluids that have a large temperature difference. Maintenance cost is lowest as compared to other types for the same size of the unit.