Air Mixer provides a robust solution to reducing air stratification in the plenum and coil freeze-ups. The design was conceptualized by observing the existing problem and devising solution that best fit the market requirement in a cost-effective manner. A vast range of programs were used and studied to see what design and size worked the best. Few principles were considered,
- Layer by layer meshing of two gradients of air across the full plenum.
- Effectively churning the air within the Plenum/ box itself without requiring additional space
- Optimizing the flow field with high ratio of mixing per unit of air.
- Energy savings
Problems of Air Stratification/ Freeze ups/ Failures
In HVAC Air Handling system, air stratification stems from improper design structure, which prevents air streams of different temperatures to mix up. As a result, it becomes exceedingly difficult to effectively operate an Air handler as well maintain the Indoor air quality. In the winter because of no mixing, coils often get frozen, which can damage the coil while causing freeze stat trips. In summer, both streams of air were not mixed properly causing additional load on the heat transfer coils leading to large energy bills. In the long run, the air mixing problem became a serious matter as outdoor air percentage starts increasing as a result of mandate IAQ requirement.
Current Problem vs. Effective economical solution
We have seen many solutions adopted in the market to resolve the problem of air stratification and inability to mix air with two different temperatures. Earlier glycol additives were used to prevent frozen coils, dampers, high velocity jets, baffles and specially designed apparatus were conceived to help in mixing. In each case, use of a technique slacked the capacity of the air handler causing lower capacity, higher pressure drops and increase of motor horsepower. Some custom designed mixers were offered in the past to improve mixing criteria, however, it was found that air was forced to pass under high velocity through narrow chamber. These mixers required more downstream space, non-uniform velocity profile and high pressure drop. Also it is seen that non uniform velocity caused additional pressure drop at the downstream components like coils, filters etc.
The mixing device is one of the most effective means of stirring air as well uniformly mixing two gradients of air temperature homogeneously without causing abrupt temperature blocks in certain areas at the coil entry. The downstream area is of the mixing device is shorter than standard mixing devices in the industry given only 2-3ft of distance is required to optimize mixing process without causing stratification.
Applications
- Existing Air Handling Unit having problem with mixing two types of air
- New Air Handling Unit
- Any Area/ Enclosure bringing two types of air and requiring mixing
- Dealing with two extreme temperatures
Preventing expensive extensions and other appendages inside unit
Benefits
- Energy savings by reducing waste heat vis-à-vis lowering operating cost
- Long Life of coils from getting damaged or rusted
- Improved coil efficiency
- Lower equipment down time
- Improves indoor comfort
