AT THE HEART OF THE ROAD TRANSPORT INDUSTRY.

Call our Sales Team on 0208 912 2120

"Supercharging Oil Engines Pays " Sir Harry Ricardo WHILST the

24th November 1950
Page 41
Page 41, 24th November 1950 — "Supercharging Oil Engines Pays " Sir Harry Ricardo WHILST the
Close
Noticed an error?
If you've noticed an error in this article please click here to report it so we can fix it.

Which of the following most accurately describes the problem?

supercharging of the V, spark-ignition engine was not worth while, except in aircraft and racing cars, it paid hands down in the case of the four-cycle oil engine, more particularly in the road-vehicle field. said Sir Harry R. Ricardo, B.A., LL.D., F.R.S., in a paper which he read in London last Friday.

The development, however, was dependent upon a suitable blower which had not so far been made available. In road-vehicle service, what was required of the engine was high torque at low engine revolutions: ultimate power at maximum engine speed was seldom used and was of minor interest. The oil engine, said Sir Harry, should be ideal for this, because its behaviour when heavily supercharged was excellent.

If by supercharging, double the normal full-load torque could be obtained at the lower end of the speed range, it would appear that an engine of only 5-litre capacity would give about the same road performance as an unsupercharged 8-litre engine.

Unfortunately, no form of blower existed that would provide the characteristics required—the delivery of a small volume of air against a high pressure when running slowly, and of a larger volume at a lower pressure when running fast. After explaining the shortcomings of known types of blower to meet these conditions, the speaker said that some form of piston blower was the real answer.

Sir Harry maintained that an oil engine of reasonably robust but orthodox design could safely stand up to a degree of supercharge that would double its torque at low speeds without intercooling. If, however, the same supercharge were applied and made full use of all its top speed, thus doubling the maximum power, the heat flow would be such as to necessitate oil-cooling of the pistons, and probably the employment of sodium-cooled exhaust valves as well. The paper was read to the Institution of Mechanical Engineers. '

Tags

Locations: London

comments powered by Disqus