Air to Air Heat Exchangers

What are Air To Air Heat Exchangers?

Air to air heat exchangers are closed loop cooling systems that employ heat pipe mechanisms to transfer heat from an electrical casing to the outside. Where ambient temperature is suitable for heat piping, air to air heat exchangers are an efficient way of cooling since the unwanted heat is the engine that drives the system.

The only requirement to operate the two circulating blowers or fans is power. Air to air heat exchangers offer a novel and inexpensive way of cooling closed-loop enclosures. Apart from air circulation fans, exchangers utilize no power and are quite quiet in operation. In many cases, they provide a viable substitute for enclosure air conditioners.

How Does an Air To Air Heat Exchanger Function?

Air to air heat exchangers use heat pipes to move heat from hot enclosures to the cool ambient air. The heat pipes are evacuated tubes occupied by a special refrigerant fluid. This refrigerant boils while absorbing heat energy from the hot air inside the enclosure.

The resultant vapor escalates to the top of the tubes and condenses because of the cool ambient air while releasing its heat, a continuously repeated procedure.

How to Choose an Air to Air Heat Exchanger

To choose the most efficient type of enclosure cooling system, several factors must be considered:

• Heat loss from electronic components inside the enclosure
• Maximum ambient temperature
• Required internal enclosure temperature
• Dimensions of the enclosure to be cooled
• Available mounting space for cooling devices
• Type of environment to place the enclosure
• Required operating voltage for the cooling product

The final operating environment differs from user to user or might not be known, but it is pertinent to know extra elements beyond total ambient temperature.

Important factors to consider include sanitation of external air, cost and complexity of maintenance, physical space margins, noise limit, the potential for hose-directed spray close to the cooling product, possible magnetic interference from fans’ motors, and possible exposure to cold temperatures, rain and blowing dust.

Types of Air to Air Heat Exchangers

Types of air to air heat exchangers include:

Plate Types

Plate-type air to air heat exchangers offer a low-cost and effective answer to reduce heat and cool loads in the treatment of process air. The plates on the air to air heat exchanger physically separate the supplied and exhausted air, with the supplied air moving on one side and the exhaust air moving on the other. The exhaust air is utilized to precool or preheat incoming air supplies without mixing the air streams.

There are two differences in the plate type air to air heat exchangers, which offer a range of benefits. These include:

Dimple Plate Heat Exchanger

These have improved versatility and toughness for heavy-duty applications. The dimples on the plates enable the heat exchangers to sustain low pressure drop and enhance turbulence. The flat plates and the dependable dimple patterns allow easy cleaning and maintenance.

Wave Plate Heat Exchangers

These are a welded metal heat exchanger that combines an inline dimple pattern and wave patterns on the plates. This combination enables the heat exchangers to bring more turbulence and structural integrity while maintaining a low pressure drop. They also have heavy-duty plates that are simple to clean.

Tube Types

These accommodate higher pressure and temperature than wheel and plate types. They are also a perfect choice for environments that are prone to dustiness or have a high particle concentration in the air.

Shell and tube air to air heat exchangers offer optimal performance for recuperating valuable heat energy from ovens, dryers, kilns, and furnaces.

Wheel Types

They have a space-saving design, offering higher efficiency for their volume than larger plate types of heat exchangers. The spinning wheel’s prolonged surface makes contact with heat from the exhaust and then transfers it to the cool incoming air, though each stream stays separate. Wheel-type heat exchangers are appropriate for hot and cold air ducts.

Applications of Air to Air Heat Exchangers

A variety of industries depend on air to air heat exchangers to gather heat energy lost in heating applications. They are important to various industrial applications, recuperating heat to save energy, lower expenses, and improve operational efficiency. Some of the applications of tube and plate types include:

• Heat recovery
• Air handling units
• Airstreams de-humidification
• Electrical equipment cooling
• Drying rooms or kilns heat recycle
• Oven heat recovery
• Boiler flue economizers
• Combustion air preheating
• Catalytic oxidizers
• Process air cooling
• Thermal oxidizers
• Spray dryers
• Gas cooling or condensing