AU2015101846A4

AU2015101846A4 - Hypersonic screw propeller

Info

Publication number: AU2015101846A4
Application number: AU2015101846A
Authority: AU
Inventors: Dzhabrail Kharunovitch Baziev
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-12-24
Filing date: 2015-12-24
Publication date: 2016-02-18
Anticipated expiration: 2023-12-24

Abstract

Abstract Original wing profiles are proposed that significantly increase the aerodynamic qualities of propellers. The advantage of aircraft propellers, based on these proposed profiles with sharp front edge is that the whole air inflow is directed only to one, rear blade plane, while the front plane completely is eliminated from interacting with air inflow and relieved from such negative effects of the classic propeller as flutter, shock wave resistance, blade vibration and negative propulsion on the front blade plane. Furthermore, the propellers with these profiles are capable of operating at hypersonic speed, providing extremely high propulsion that exceeds that propulsion of classic propellers of the same size by 3 to 5 times. 1h Fig. 1 1) Fig. 2 c) Fig. 3

Description

AUSTRALIA PATENTS ACT 1990 INNOVATION SPECIFICATION HYPERSONIC SCREW PROPELLER The following statement is a description of the invention: 1 HYPERSONIC SCREW PROPELLER V63N 1/02, 1/12 V64S 11/04, 11/20 This invention is related to naval and aviation construction, i.e. to water and air crafts, specifically to marine and air screw propellers to use them on vessels, helicopters and propeller airplanes of any type or purpose. Any references to methods, apparatus or documents of the prior art in the following are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge in Australia or any other region of the world. There are many classic screw propellers with rounded front edge blades. The front plane of a propeller blade has a negative incidence angle relative to air inflow in the rotational plane similar to the top surface of the wing with classic profile, which also has a rounded front edge, dividing air inflow and directing it to the top and bottom planes [S. M. Gorlin. Experimental aerodynamics. M., University, 1970, page 371]. This specific geometry of the propeller gives it a propulsion limit. Classic propellers achieve the propulsion limit at the propeller's rotation frequency of n = 2,500 - 3,000 rpm, while the further increase in rotation frequency yields a decrease in propulsion. Exactly this geometric deficiency of the classic propeller impedes, even today, the development of non-jet aircrafts, which is several times better economically and environmentally than jets, but slower in speed due to the low efficiency of the propeller. The technically closest to the claimed propeller is a propeller in Russian Federation patent claim No. 2011127563, "The screw propeller", benchmarked as a prototype. This propeller has a rotational axis with blades that rotate around it. Each one of them has a front and rear plane, front sharp edge and back edge. Furthermore, the front plane of every blade has a straight line flat area. The front edge of the blade, sharp as a knife, cuts all of inflow air and sends it to the rear plane (a lower plane, if referring to a helicopter) of the blade. As a result, propulsion increase is achieved along the pressure plane. The positive quality of the prototype is the relief of the front plane from interaction with inflow air, which relieves this plane from the detachable streamlining, flutter and shock wave drag, which are insurmountable negative characteristics of blades with classic profile, which have an blunt front edge, which guides part of an inflow air to the front plane. However, the prototype propeller has a big technical deficiency: the front plane of every blade is completely excluded from creating the propulsion, because the rarefaction of air is not formed above it. The challenge of the proposed technical solution is an increase in the limit of propulsion of the propeller and its performance. This challenge is solved by having a screw propeller with rotational axis and blades that rotate around it. Each one of them has the front and rear planes, sharp front edge and rear plane. Furthermore, the front plane of every blade has a straight line flat area, positioned at a negative angle (y) to propeller plane (MN).

2 Thanks to the presence of the negative angle between the front plane of the propeller and rotational plane of blades, a bigger air rarefaction is achieved at the front plane of propeller blades, which yields an increase in propulsion and performance of the propeller. When the blades achieve final speed of Mach 11 (661.6 m/s), a big rarefaction (P = -102 kPa) is formed at the front plane of the blades. The new propeller profile is similar to the new profile of the aircraft's wing (see Russian Federation patent No. 2461492, dated November 1, 2010) with the front edge, sharp as a knife, which cuts all of inflow air and sends it to the lower pressure plane. The preferred profile for propeller blades has the following two options: a) Lower contour that connects the sharp front edge with the rear edge, designed as a convex curve (Fig. 1). b) Lower contour that connects the sharp front edge of the blade with the rear edge, designed as a line segment (AS). (Fig. 2). Using the new propeller profile has the following advantages over other propellers: 1. Fully eliminates the interaction of the front (top) blade plane with inflow air. 2. All of the inflow air is guided to the rear (bottom, in helicopter case) pressure plane, which yields an increase in air pressure on this plane. 3. Blades are fully relieved of detachable streamlining, flutter and shock wave drag. Furthermore, blades are fully relieved from vibration and noise, which are inherent deficiencies of blades with classic profile. 4. Propellers, whose blades are designed with a sharp front edge, along with a negative adjustment angle (y), do not form negative propulsion on their front plane, which usually happens with propellers with classic profile. Propeller blades with a new wing profile lack a twist, which is the case for the blades with blunt front edge, but have the operating adjustment angle along the front plane. The purpose of the adjustment angle is to move the front plane of the blade into the shadow of the air inflow, providing it with a negative incidence angle (y). Such geometry along with the sharp front edge, eliminates the interaction between the front plane and air inflow, and creates conditions for a larger air rarefaction, than with classic profile, on this plane. Furthermore, the front blade plane with Basiev profile, creates air rarefaction at the minimum angle (y = -1) and increases the rarefaction level, as the angle (y) increases, as well as propeller rotation and angular velocity of blades. It was experimentally determined that at (y = -3'), the air rarefaction along the front plane begins when the angular velocity, at blade tips, reaches (umin = 90 m/s), which can be considered as the lower threshold. A preferred embodiment of the invention is explained by drawings below: - Fig. 1 shows the blade profile option, where the lower contour is designed as a plane curve (profile B-2). - Fig. 2 shows the blade profile option, where the lower contour is designed as a line segment, which connects the front and rear edges (profile B-1).

3 - Fig. 3 shows the new wing blade profile and corresponding operating angles, scale 1:1 (profile B-3). - Fig. 4 and 5 show marine propellers for watercrafts with blade profile shown in Fig. 2. Description of Figures Fig. 1. Blade cross-section profile with sharp front edge, front plane, which is largely designed as a line segment (AB), which gradually becomes a plane curve (BC), forming the sharp rear edge with the lower profile contour (AC), designed as a plane curve. Line MN is the rotational plane of the propeller relative to which the upper contour is positioned at a negative angle (y). DC = h, which is the height of the blade projection onto the plane, parallel to the propeller shaft axis (Fig 1 - 2). Fig. 2. Blade cross-section profile with even sharper front edge, formed by a small angle of divergence of the upper and lower contours (P). The lower contour (AC) is designed as a line segment. The upper contour is positioned at a negative angle (y) relative to rotational plane of the propeller (MN). DC = h. This is the best option for propellers. Fig. 3 and 3.1. Blade cross-section profile, whose straight line areas of the upper (AC 1 ) and lower (BD) contours are parallel to each other. This is the best option for the wing of a heavy duty airplane. Furthermore, the upper contour is positioned at a negative angle relative to the longitudinal axis of an aircraft, as shown in Fig. 3. (AD 1 ) = b, which is an outer section chord, while (AD) is an inner chord. Fig. 4 and 5. General view of the propeller with blades, designed with the proposed B-2 profile. Using propellers with new profiles, achieves the following, besides the abovementioned advantages: 1. New profile propellers do not have a limit to rotation frequency and propulsion, defined by the engine power and blade durability properties, up to 12,000 - 15,000 rpm. 2. Diameters of helicopter carrying propellers, with proposed profiles, may be reduced up to five times with simultaneous increase in rotation frequency, transferred to the propeller shaft, up to n = 4,000 rpm and significant simplification of gearboxes. 3. The reduction in propeller diameter yields a weight reduction of propellers by several times and reduction in response time of the propeller by several times as well. 4. The payload of helicopters, equipped with carrying propellers with proposed profiles, may reach 55 - 60% from the takeoff weight.

4 5. Propulsion of blades with a new profile is proportional to the air inflow speed (angular velocity of blade center) up to hypersonic speed, while classic profile blades have a limit of v= 1M. References 1. S. M. Gorlin. Experimental aerodynamics. University. M. 1970. 2. D. K. Basiev. Basics of a single theory physics. Pedagogy, M., 1994. 3. Russian Federation Patent No. 2461492. In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term "comprises" and its variations, such as "comprising" and "comprised of' is used throughout in an inclusive sense and not to the exclusion of any additional features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art. Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms. Any embodiment of the invention is meant to be illustrative only and is not meant to be limiting to the invention. Therefore, it should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.

Claims

1. The propeller with rotational axis with ability to rotate blades around it, each of which has a front plane with straight line area and a rear plane, front sharp edge and rear edge. Furthermore, the front plane of every blade has a straight line flat area, which converges to the rear edge as a smooth convex curve, which differs by having the straight line area of the front plane, in non-working mode, positioned perpendicular to the rotational axis of the propeller. To switch the propeller to a work mode, the front (upper) plane of the blades shall be positioned at a negative angle (-a) at 1 minimum.

2. Propeller as in claim 1, which differs by having the rear plane of the blade, connecting the front and rear edges, designed in the shape of a smooth convex curve.

3. Propeller as in claim 1, which differs by having the rear plane of the blade, connecting the front and rear edges, designed in the shape of line segment.

4. Propeller as in claim 1 or 2, which differs by having the mid-section and blade chord constant along the entire blade length.

5. Propeller as in claim 1 or 2, which differs by having the mid-section and blade chord vary along the entire blade length. * * *