Superchargers and Supercharging - 19th National Aeronautical Meeting Paper 310041

CLASSIFYING the superchargers used for present aircraft and automobile service as Roots, centrifugal and vane types, the author states that the vane type for this service is a more recent development than the other two and describes each type. He states further that the ideal type should satisfy many requirements closely related with those of a well-designed engine-such as being light, compact and reliable-and that the practice of supercharging has increased considerably during the last few years.
The comparative performance of superchargers is treated at some length, and engine-performance data are presented. The power developed by an engine equipped with geared-centrifugal, turbo-centrifugal and Roots superchargers is illustrated by curves, control methods are compared, net engine-power is computed, and flight-test data on comparative performance are analyzed.
After discussing the effect of supercharger capacity on performance, the author states that, in the selection of a supercharger for use on an airplane designed to meet definite performance requirements, the question arises whether it is advisable to choose a supercharger of sufficient capacity to maintain sea-level pressure to the maximum useful altitude or to choose one of smaller capacity that requires less power. Selection of the best supercharger-capacity depends largely upon the way in which the type of supercharger in question affects the engine power, the percentage of engine power required by the supercharger and the kind of service for which the supercharged engine will be used.
Following a statement of the influence that supercharger capacity has on performance and an analysis of the effect of “boosting,” the author concludes that the supercharging of engines of low compression-ratio is impracticable and that it is desirable that an engine have a compression ratio of at least 4.5:1.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:

Application of Laminar Flow Control to High-Bypass-Ratio Turbofan Engine Nacelles


View Details


A Review of Curtiss-Wright Rotary Engine Developments with Respect to General Aviation Potential


View Details


Variable-Geometry Exhaust Nozzles and Their Effects on Airplane Performance


View Details