From the Table 1 summary, compressor operating efficiency considerably impacts overall power requirements; power is directly related to fuel consumption and, hence, operating costs. Further, power generators on board the deicing vehicle must be upsized to accommodate a more power hungry, inefficient compressor. Since most modern deicing vehicles favor a hydraulically driven compressor drive arrangement, this implies the use of a larger, more costly power source, pump and hydraulic motor. Clearly, compressor efficiency must be at the top of the list for choosing a potential air source solution, if overall system downsizing, operating cost and emissions reductions are at all relevant.
For the reasons discussed, the mechanically driven centrifugal compressor technology has been the choice of deicing vehicle manufacturers for several years now.
With what appears to be a growing trend and global initiative toward energy footprint, emissions and operating cost reductions, GSE manufacturers have also adopted a trend to develop equipment that can accomplish more with less, i.e., do a better job while reducing cost burden to their customers, all while maintaining an edge in a very competitive global market.
For forced air deicers, increased airflow is desired since this enables improved blow-off performance at greater distances due to the increased jet core to surface area ratio. Such performance is desired to better accommodate deicing needs of large aircraft such as the Airbus A380.
As a result of these challenging objectives, new compressor designs promise to move the forced air deicer performance and efficiency state-of-the-art forward. These next generation products offer increased air flow of 140 PPM (1,830 CFM) courtesy of new generation, ultra-efficient compressor stages.
Such a system with this level of efficiency performance incurs only modest power increases; the 1.9 PR at 140 PPM flow operating point is attained at 81 percent overall efficiency, resulting in 96 horsepower of compressor power at the typical 20 degrees F @ 14.5 psia inlet conditions. (See Figure 3.)
As many deicing vehicles in service today are already equipped with this level of compressor power rating, upgrading to these newer high performance compressors can be accomplished with little other modification to the existing vehicle system. The peak efficiency of this device is attained at the exact operating point of interest!
About the Author: Robert B. Anderson, MSME, is senior technologist at the AirPower® Group of companies, which includes the Vortech Engineering and Vortron product brands, where he has worked since 2001.
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