General description of scraped surface heat exchanger
Having a fully-blended and homogeneous production and at the same time providing the highest heat transfer of working fluids are the desired outcomes of industrial heat exchangers. The following types of SSHEs are promising approaches to achieve these outcomes.
Rotating, tubular dynamic scraped surface heat exchanger
This type of SSHE consists of two coaxial cylinders. The inner cylinder is called the rotor and the outer cylinder is casing or stator. Blades, with their numbers typically varying from 1 to 4, are mounted on the rotor with the rotational speeds typically between 1 and 1000 RPM.
Reciprocating, tubular dynamic scraped surface heat exchanger
This type of heat exchanger also has a similar structure to the first, but the rotor is reciprocating, with a frequency of 10 to 60 S per minute.
Rotating, plate dynamic scraped surface heat exchanger
This type, which is highly used for cooling and heating with various rotor speeds, consists of several blades arranged in series inside a shell that clean the inner surface of the SSHE against substances.
As schematically depictured in Fig. 2, the first type of heat exchanger is used in the current study in which a rotor with two blades rotates to enhance the heat transfer rate and provide well-mixed, homogeneous ice cream. As shown, this type of heat exchanger comprises of two coaxial cylinders between which the working fluid flows. The fluid enters the heat exchanger from one side with a mass flow rate of and temperature of , swept away by the blades, and then driven to the outlet to exit with a lower temperature of . The movement of the blades, which hinders deposition and agglomeration, is responsible for making a high-turbulent flow condition and, consequently, uniform temperature distribution.