Application of VM chiller, i.e., Villemeer chiller in Maipt temperature control machinery

The VM Refrigerator is called the Vuilleumier Refrigerator. It works as follows:
  

Heat engine cycle part

Isothermal heating expansion: Natural gas and other heat sources burn outside the hot chamber and input heat to the working medium in the hot chamber, and the working medium performs the isothermal heating expansion process at high temperature T h, changing from state 1 to state 2. In this process, the working medium absorbs heat Q and pushes the piston to expand and do external work.

Cooling and heat removal: After the expansion of the working medium on the heat engine side, the temperature is first cooled by the high temperature regenerator, the temperature is reduced from T to the medium temperature T1, and then the heat is discharged to the medium temperature environment, that is, the hot air is blown to the required heating room space, providing useful heat Q1 and then flowing back to the high temperature regenerator to absorb heat and complete the cycle on the heat engine side.

Heat pump cycle

Low temperature endothermic expansion: the working medium absorbs heat from the low temperature side (such as outdoor environment in winter), absorbs heat QL under low temperature TL, keeps the temperature TL unchanged, and expands the volume.

Heating compression: After the cold regenerator is heated, the temperature rises from TL to, and then the heat is discharged to the middle temperature T1 and compressed, and the reverse flow is returned to the low temperature side through the cold regenerator to complete the heat pump cycle. In refrigeration applications, this cycle absorbs heat from the low temperature area and displaces it to the medium temperature area, thus achieving the cooling effect.

In the whole working process of the VM refrigerator, the heat engine cycle and the heat pump cycle are coupled through mechanical connection or working medium pressure transfer, etc. The work generated by the heat engine cycle is used to drive the heat pump cycle, so that the working medium can absorb and discharge heat in different temperature ranges, and finally achieve the purpose of refrigeration.