# Auto-Sizing Fans & Compressors

From v3.31 onwards, FluidFlow includes a powerful Auto-Size feature which allows engineers to automatically size a range of elements including Fans & Compressors. This series of examples demonstrates how these boosters can be automatically sized, based on a design flow rate or design duty pressure rise. The system used in this example has a total pipe length of 55.0 m, the pipework is 50A JIS 50mm steel and the system experiences an elevation change of 10.0 m. The fluid used in this example is nitrogen. A copy of this model can be found in the folder: "QA Equipment Sizing". Auto-Sizing Fans & Compressors - Design Flow. Set the Automatically Size field for the booster to "On" and enter a Design Flow rate of 0.25 kg/s. Figure 1 shows the data entry for the fan and Figure 2 gives an overview of the performance of this device in this system. Figure 1: Data entry for Auto-Sizing a Fan or Compressor (Size for Flow). Figure 2: Auto-Sizing a Fan or Compressor (Size for Flow). From this analysis, we have established the fan operating performance. The duty pressure rise has been calculated as 98268 Pa. Auto-Sizing Fans & Compressors - Design Duty Pressure Rise. Set the Automatically Size field for the booster to "On" and enter the Design Duty Pressure Rise rate of 98268 Pa as established in the first simulation (Figure 2). The Input Editor for the fan should now appear as shown in Figure 3. Figure 3: Data entry for Auto-Sizing a Fan or Compressor (Size for Pressure Rise). Figure 4 shows the calculated results for the fan. As we can see, FluidFlow has established a mass flow rate of 0.25 kg/s, i.e., exactly matching the results from Figure 2. This element has therefore been automatically sized successfully using both available sizing options. Using this data, we can now select a suitable fan from the database or request a proposal from a vendor. Figure 4: Auto-Sizing a Fan or Compressor (Size for Duty Pressure Rise). For further information, a detailed example of automatically sizing components is available at: Design Examples | Auto Equipment Sizing.