Past Research

 We are developing a meso-scale vapor compression refrigeration system that can be used in cooling small machines generating large amount of heat. The cooling capacity of the system is 80W in 60×60 mm². The refrigerant is R-123 which has the evaporating temperature of 28?at 1 bar. The condensing temperature is 60?at 2.8 bar.

Fig.1 The refrigeration system and the refrigeration cycle

 1. Previous work

A. Optimal design of micro-channel evaporator
The micro-channel evaporator with lateral gaps was designed and manufactured. The design parameters of the evaporator were selected by experiment. We also visualize the flow inside evaporator to observe the phenomena during evaporation

     Fig.2 Prototypes of the evaporator and the flow visualization of the refrigerant

B. Development of meso-scale rotary vane compressor
The meso-scale rotary vane compressor was designed and manufactured as shown in Fig. 3. The system is oil-less system. For lubrication, the vane was made of graphite and the rotor is coated with MoS². The pressure ratio and the flow rate are 2.8 and 10 lpm, respectively.

Fig.3 Meso-scale rotary vane compressor

2. Present work

A. Control of vapor compression refrigeration system.
The dynamic modeling of the refrigeration system will be conducted and verified. We will control the system with proper control theory.