DE696655C - Motor nacelle for air-cooled aircraft engines equipped with a single or multi-stage charging fan with cylinders arranged in a star shape - Google Patents

Description

GERMAN EMPIRE

ISSUED
October 19, 1940

REICH PATENT OFFICE

PATENT LETTERING

JVi 696 655 ν CLASS 62 c GROUP 12 oi

B182483 XIJ62C

3) ipl.-3tig. Baron Igor v. Heyking in Munich

has been named as the inventor.

Bayerische Motoren Werke Akt.-Ges. in Munich

Patented in the German Empire on March 24, 1938 "Patent issued August 29, 1940

The installation of air-cooled aircraft engines, especially of those with cylinders arranged in a star shape, in their own motor pods was primarily because of 'this resulting disadvantageous cooling possibilities not carried out, nevertheless an arrangement of the motor in the interior of a streamlined nacelle is very advantageous in terms of flow is.

In the course of the arrangements already proposed in this context, it became known, for example, to provide one or more separate inlet openings for the cooling air at the front of the motor nacelle and to regulate the cooling air throughput through the nacelle with adjustable flaps. In addition, the power was transmitted to a pressure screw built into the rear end of the gondola with motors built into gondolas. . ^λ

The invention now makes it possible to use what are individually known per se Arrangements allow the installation of a motor with cylinders arranged in a star shape in a Gondola! such that firstly, in the presence of a charge fan, the charge air cooler, furthermore possibly oil cooler 0 sufficient cooling of the same is guaranteed, secondly the supply of the Combustion necessary air to the engine without any disturbance of the aerodynamically the most favorable external shape, the gondola is made,

being the during, the flight on the gondola acting back pressure is largely exploited, and thirdly, the volume, moderately adjustable discharge of the cooling air Disturbance of the outer shape of the gondola durc'nv ;? is led. '.Ii:

The air or the heated mixture heated by the pre-compression is at Presence of two charging levels between ίο the first and second stage through intercooler passed and then passes through the arrangement according to the invention Intake pipes located at the front of the engine into the cylinders. The intake pipes in front of the house allow further recooling of the pre-compressed Charge, or if only one charge level is provided, can be more pronounced Cooling devices through those with fins

ao provided suction pipes also a satisfactory Cooling can be achieved.

At the front of the gondola are in this. Relationship in itself: as is known, openings are provided that serve to

as again using the here prevailing back pressure cooling air to the intercoolers installed between the fan stages or the intake pipes with cooling fins and furthermore the engine to feed cylinders. So there are ·, besides that Engine also includes all devices used for recooling the pre-compressed cargo housed inside the gondola.

In order to have other necessary cooling devices, for example oil coolers for the lubricating oil in the MotoF circuit, coated by the air entering the front of the nacelle under dynamic pressure, in addition to the inlet openings for cooling and charge air, adjustable openings are also attached, through which separate from Main cooling air flow - adjustable amount of air flows into these additional cooling devices. These coolers are expediently located in front of the engine cylinders, and the cooling air is combined with the main cooling air flow after it has brushed them. On the circumference of the nacelle, adjustable openings are provided, through which the cooling air entering the front, the charge air or charge mixture cooling units and the engine cylinders is discharged. These openings through their respective shared opening cross section of the cooling air throughput SS amount is determined to be _{erfindungsge-%} measured by along the Gondelumkleidung displaceable flaps more or .Less held wide open. Advantageously, the parallel displacement relative to the previously übliehen Sdhwenken the flaps acts at a fixed point in so far as this an unfavorable change in any position - is carried out fluidically favorable form of Pondel.

^ Jv pie propeller is at the fictional - '^ gg & ate Installation of an air-cooled Stern-Ätotor in a gondola in a known '"manner attached to the end of the gondola and designed as a pressure screw.

In summary it can be said that it is. The invention allows' an air-cooled radial engine under the most favorable cooling conditions / attention should be particularly drawn to the fact that due to the back cooling of the pre-compressed charge ^7S • both in the radiators and through the intake pipes provided with cooling fins at the front of the engine, a much lower level Cooling of the motor cylinder necessary ISt _{3 to be} completely built into a line nacelle with a favorable aerodynamic design. Another advantage to be mentioned is that the dynamic pressure that occurs serves to increase the pressure of the air sucked in by the charge fan and the air introduced for cooling purposes, which in both cases increases the efficiency in a simple and power-saving manner.

The approximately parallel to Motorgo.ndelwandung · displacement of the air outlet openings closing flaps provided at each position, the compliance of the aerodynamically favorable shape of the engine nacelle installation without protrude generating turbulences ⁹ · "> parts.

The figure shows a schematic section through an engine installation nacelle according to the invention, for example a fan with two charging stages being shown. On the front side of the gondola r, the inlet opening 2 for the air sucked in by the first blower stage 3 is arranged in the middle. Furthermore, openings 4 are made on the front side through which the cooling air for the charge air cooler 5 arranged between the first charge stage 3 and the second charge stage 12 or for the intake pipes provided with cooling fins and for the engine cylinders 6 flows in. By means of the adjustable flaps 8, which can be moved approximately parallel to the Mötorgondelwandung, the cooling air flow rate is regulated depending on their opening position. Except for the inlet openings 4 for the main cooling air flow. are "5 adjustable at the front or by" flaps 13 openings 14 mounted, the further ^cooling. facilities, for example, oil coolers 7, separated out air for cooling from Hauptkuhlluftstrom The drive of ^{| ao} rearward pressure screw 9 is effected via a remote drive shaft _ι ο Λ being at any

Place a gearbox between the drive shaft ι ο and propeller 9 can be switched.

The arrow in the figure indicates the direction of flight.

Claims (1)

Claim: Mator nacelle for air-cooled aircraft engines equipped with a single or multi-stage charge fan with a star shape. arranged cylinders that work on ledpe at the end of the nacelle! ) provided entry opening (2) flows in, while the air necessary for charging the charge air cooler is introduced through ^{openings (4) in the end face of the nacelle 1 separated} from the opening (2) and, after the radiator has been coated, serves to cool the engine cylinders the cooler (5) serving for the recooling of the pre-evaporated charge air and the oil cooler (7) are arranged inside the nacelle, the oil coolers (7) supplying the cooling air separately from the main air stream and. The flaps (8) regulating the cross-section of the cooling air inlet are designed to be displaceable parallel to the wall of the gondola. 1 sheet of drawings