What is a two -phase flow?

The two -phase flow is a process in which the fluid changes from one phase to another, usually from gas to liquid or from liquid to gas. This process is commonly used as a heat transfer mechanism. It is commonly found in cooling units, air -conditioning systems, heat pumps or other climate control systems.

phase is a change in the physical condition of the material. For example, water has three physical conditions: solid, liquid and gas. As an illustration, when the material is transformed from a solid to liquid or from gas to liquid, this change is called a phase. During the phase change, energy is transferred. This energy either helps start the phase change, or is released during the changing phase.

For two -phase flow, only two of these phases, usually liquid and gas are considered. For example, a typical refrigerant liquid usually turns into liquid gas when it is compressed and back into the gas when it is extended. Primary energy transmission method during this two -phase toKU is usually with thermal energy.

This two -phase flow fluid or refrigerant is specially selected depending on the operating conditions of the system. The key to choosing two -phase fluid is to consider the compressibility of fluid as the ability of heat absorption as liquid. In addition, this fluid should have the ability to change the phase at specific operational pressures in a closed system.

For example, a typical air conditioning unit contains a compressor pump, an expansion valve and two sets of heat transfer coils. All these components cooperate and move phase -changing fluid through the system. The typical two -phase flow for the liquid/gas system consists of a four -stage process.

The gas refrigerant is first compressed by a pump during which the gas phase is changed to liquid. Likid then flows into the first coil of heat transfer and releases its thermal energy. Pressurized liquid afterIt excludes it via the expansion valve and into low -pressure cooling coils. As the liquid leaves the valve, it turns the phase from the liquid to the gas absorption of thermal energy again.

Some two -phase systems, if equipped with special valves and switches, can be controlled the opposite. The well -known reversible system is a heat pump. In warmer months, the system cools the interior of dwellings and in colder months the system is reversed and provides heat.