Breakthrough for higher efficiency with lower operating noise
With the help of a diffuser can now also be the loss to the impeller outlet are significantly reduced.
will Mulfingen, 03.29.2012, issued in refrigeration and cooling systems must be exhaust heat to the ambient air via a heat exchanger. Fans therefore encourage cooling air through the heat exchanger and thus improve the heat dissipation. For very efficient, quiet and durable fans there are a number of opportunities in design and interpretation. A new, passive component, the so-called diffuser, provides a significant improvement of efficiency and noise. Its pressure-increasing effect of minimizing the leakage losses and allows a better adaptation of the fan from any standard heat exchangers.
Each medium can only absorb a certain amount of heat per degree Kelvin. Due to the potential temperature difference and the amount of heat so the required cooling flow rate is fixed. This air flow must be a fan through the heat exchanger under consideration promote. Since refrigeration systems are usually operated at high duty cycle, is an economical use of energy used in driving important because each additional watt costs money. By a suitably-Marinated fan impeller, an air flow is generated. It is separation and backflow be avoided because they produce energy losses and unwanted noise. This procedure is state of the art, all manufacturers now dominate more or less. ebm-papst, the leading manufacturer of motors and fans, is now one step further: With the help of a diffuser can now also be the loss to the impeller outlet are significantly reduced.
How to
In order to promote a flow of air through a heat exchanger, a pressure gradient is necessary that overcomes the flow resistance of the exchanger. Normally flows through the air conveyed at high speed on the exit side of the fan and dissipated into the environment. Dissipation means that the kinetic energy of the flow into heat, which can not technically be used will be converted. By applying a suitable diffuser can be a large part of the dynamic speed energy converted by delaying the flow in static pressure. This re-conversion increases the pressure increase of the impeller. For aerodynamically optimized tuning of all components can thus significantly improve the efficiency, thereby reducing speed and thus a noise reduction are possible.
More ways to adapt
In practice, the use of a diffuser means in addition to a lower power consumption and greater freedom for users and developers. Thus, the coordination of the diffuser to be optimized for different properties depending on the application down. At constant energy use a higher flow rate is possible as well as lower energy consumption at the same air power. Even the acoustic behavior of the diffuser can be significantly improved. This is just for sound-sensitive environments (eg night-time operation of refrigeration and air conditioning) is important.
The magnitude of the potential energy savings or increased efficiency and noise reduction is significant with a diffuser for optimum heat exchanger market. Thus, the replacement of a normal fan allowed to guard against a diffuser with supporting grid, grille and savings of up to 20% in energy consumption and simultaneously from the retainer by 4 dB (A) noise level. However, if the higher efficiency of the fan used with a diffuser, it promotes the same power input an approximately 7% higher flow rate, while still about 3 dB (A) of reduced noise emission. The values are to be regarded as average values. Depending on the individual design, the optimization of efficiency either be used to reduce power consumption or to increase the air capacity.
