Restoration of Sea-Level Power at Altitude: Supercharging in General and, in Particular, some of the advantages of Positive Displacement Blowers

Author:  

Publisher: Emerald Group Publishing Ltd

ISSN: 0002-2667

Source: Aircraft Engineering, Vol.1, Iss.8, 1993-12, pp. : 269-270

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

IN opening this subject, it is perhaps in order to point out that the term "Supercharging" is applied where we are concerned with restoration of sea-level power at altitude. The power of an aero engine varies in proportion to the air density. For every 100 h.p. available at sea level, only 70 are available at 10,000 ft. and only 49 at 20,000 ft. In the case of high-flying aircraft, the engine thus spends most of its life developing only a fraction of its normal ground-level power, and although this may be beneficial from a "life" point of view, it seriously limits the performance. It is the duty of a supercharger to restore ground level pressure in the induction system of the engines by means of an independent charging pump. This leads to a considerable increase in performance of the aircraft, and further it also materially assists the rate of climb.