The importance of the interaction between fan and application

The FlowGrid is suitable for centrifugal fans (left) and axial fans (right) and can reduce unpleasant noise effects even when already installed.

As highlighted by ebmpapst, the interaction between fan and its application is very important. “Fans are complex flow machines whose behavior in operation is strongly influenced by their installation situation – the company comments -. This means that, when installed in the application, the fan is often not as quiet as hoped for, or less efficient than promised in the data sheet. To select the optimum fan, ebm-papst supports its customers as early as the device development stage. Today, modern centrifugal and axial fans are very efficient and quiet. However, when installed in an application – or under real installation conditions – their behavior changes if the inflow or outflow conditions are disturbed. Environmental factors such as flaps, filters, and guard grills can affect the air flow. With typical selection programs, the actual impact of these factors in operation can only be gauged to a limited extent in advance”. “ebm-papst – the company adds – incorporates decades of experience into the development of a fan. The example of RadiPac fans shows just how much the results in use can be influenced by factoring in the installation situation at an early stage of development. In this case, ebm-papst not only optimized the impeller, motor, and control electronics in terms of energy efficiency and noise emission, but also took into account the actual installation situation in AHUs to achieve an optimum result (in application)”. Besides, ebm-papst explains the benefits of FlowGrid. “If the selected fan is too loud or not efficient enough, passive components such as the FlowGrid air inlet grille can mitigate unwanted effects even when already installed. If axial and centrifugal fans are retrofitted with this, it drastically reduces noise-generating turbulence in the inflow without affecting air performance or power consumption”. “To be on the safe side from the outset, the fan manufacturer should be involved at an early stage in the development of its own device – ebm-papst concludes -. For both large and small fans, it can be equally worthwhile to analyze and evaluate the flow situation in the application in detail so as to find suitable optimization measures or the most suitable fan for the installation situation. Flaps and filters can obstruct the air flow in AHUs, and the distance to walls and heat exchangers as well as the use of guard grilles also have an effect – which is why the actual installation situation must be considered at an early stage to achieve an optimal result at the end of development”.