Comparison Of Heat Recovery Techniques - Mitsubishi Electric Lossnay LGH-15RX3 Technical Manual

CHAPTER 3 G General Technical Considerations

9. Comparison of Heat Recovery Techniques

The methods by which heat recovery devices can be categorised may be considered as follows:
Basic methods of total heat exchangersa
Heat recovery
principle
9.1 Principle construction of rotary-type
G
The rotary-type heat recovery unit is composed of a rotor that
has a layered honeycomb structure made of kraft paper, drive
motor and housing.
A large quantity of moisture absorbent material (lithium chloride,
etc.) is applied onto the rotor, and humidity is transferred.
The rotor is rotated eight times a minute by the drive motor.
G
The principle of this rotary-type is for example when cooling, the
high temperature and high humidity fresh air passes through the
rotor, with the heat and humidity being absorbed by the rotor.
As the rotor is rotating, it moves into the exhaust air passage,
and the heat and humidity is discharged to outdoors because
the exhaust is cool and has a low humidity.
The rotor rotates and returns to the fresh air passage to absorb
the heat and humidity again.
G
Function of purge sector
There are two separation plates (purge sector) in the front and
back of the rotor to separate the flow of the air. As one of the
plates is slightly shifted, part of the fresh air always flows into the
exhaust air passage to prevent the exhaust air and fresh air from
mixing. (A balanced pressure difference is required.)
36
Type
Static
(Mitsubishi Lossnay)
Rotary type Heat accumulation/
humidity accumulation
type
Method
Conductive
transmission type
Approx. 1.5 ø
Purge sector
Supply air
Bearing
Return air
Rotor rotation direction
When a purge sector is mounted, the introduction of the exhaust
air in the rotor to the air on the supply side can be prevented.
Vr: Rotor speed, Vs: Air speed in relief section
Air flow Country of
Cross-flow development
Counterflow
Power supply
Drive motor
AC 200 V 50/60 Hz
Rotor
Fresh air
Exhaust
Drive motor
Fresh sir
A
Vr
Vs
B
Return air
Japan
Sweden
Exhaust
Fresh air
Purge sector
Room side