CN105927421A

CN105927421A - Venturi jet engine

Info

Publication number: CN105927421A
Application number: CN201610229404.7A
Authority: CN
Inventors: 韦翔
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-04-15
Filing date: 2016-04-15
Publication date: 2016-09-07

Abstract

The invention discloses a Venturi jet engine comprising a jet injection device (1), an air diffusion chamber (3), and a tailing spout (4). By means of the jet flow injection principle of the Venturi tube, plenty air is engulfed into the engine body, the air obtains certain speed from the jet flow and is ejected together with the original jet flow from a tailpipe nozzle. The propulsion efficiency of the large-flow low-speed injection mode is larger than that of small-flow high-speed injection mode. What is more practical is that jet flow of the jet engine in the prior art can be used as jet injection source, which can increase the propulsion efficiency of jet engines in the prior art. Compared with jet engines such as efficient turbines and turboprops, the Venturi jet engine has simple structure, low manufacture cost, good reliability, and higher propulsion efficiency.

Description

Venturi jet engine

Technical field

The present invention relates to a kind of jet engine, belong to power engineering, particularly jet engine field.

Background technology

Jet engine is heat engine or the motor of a kind of high-velocity fluid acting by accelerating and discharge, and makes the gas high velocity jet produced during fuel combustion produce power.Major part jet engine is all dependent on the internal combustion engine of Newton's third law work.

Jet engine produces thrust by the mode being similar to electromotor/propeller combination.Both is by advancing aircraft by a large amount of gases to pusher, and a kind of is the form of the large quantity of air slip-stream comparing low speed, and another kind to be the combustion gas injection with hypervelocity streamed.Jet retroaction is definitely a kind of internal phenomena.It not as people be often desire to as be said to be what the pressure acting on air due to gaseous blast was caused.It practice, jet propulsion engine, no matter rocket, punching jetting or turbojet, be all designed to accelerate air stream or combustion gas stream a kind of device it discharged at a high speed.Certainly, do so has different modes.But, in all examples, effect final counteracting force i.e. thrust on the engine is proportional to the speed of the quality of the air-flow that electromotor is discharged and air-flow.In other words, add a little speed to large quantity of air or be provided that same thrust to one big speed of a small amount of air.In practicality, people like the former, because reducing jet velocity can obtain higher propulsive efficiency.

Different types of jet engine, no matter punching jetting, pulse jet, turbine/punching jetting or turbine-rocket, its difference is only that " thrust supplier " i.e. electromotor supplying energy and converts the energy into the mode of flying power.

A kind of aerothermodynamic duct of ramjet.It does not has any main rotating part, only comprises an expansion shape air inlet duct and a convergent contour or the outlet of convergence-expansion shape.When being forced it to travel forward by extra power, air is forced into air intake duct.When it flows through this divergent contour duct, its speed or kinetic energy reduce, and pressure can increase.Thereafter, the burning by fuel oil increases its gross energy, and the combustion gas of expansion enters air at a high speed by outlet duct.Ramjet is frequently as guided missile and the power set of target drone, but simple ramjet is not suitable as conventional airplane power set, because before it produces thrust, it is desirable to apply motion forward to it.

Pulse jet engine uses intermittent combustion principle.Different from ramjet, it can work in resting state.This electromotor is to be made up of a kind of air force duct of similar ramjet.Its pressure is higher, and structure comparison is solid.Air inlet duct has many air inlets " valve ", under spring tension effect in an open position, combustor is entered by the valve air opened, and spray into, by burning, the fuel oil gone in combustor and heated, the expansion thus caused makes pressure raise, forcing valve to be closed, the combustion gas then expanded sprays backward；Aerofluxus causes blood pressure lowering, makes valve reopen.This process is gone round and begun again.Pulse jet engine was once designed to the propulsion plant of lifting airscrew, and have controls the pressure change of resonance circulation also by well-designed duct and eliminate air inlet valve.But pulse jet engine is not suitable as aircraft power plant, because its oil consumption is high, it is unable to reach again the performance of modern gas turbine engines.

Turbine jet engine is applied to jet-propulsion and avoids rocket and the intrinsic weakness of ramjet, because have employed turbo-driven compressor, therefore when low speed, electromotor also has enough pressure to produce powerful thrust.Turbojet works according to " cycle of operation ".It is inspiration air from air, compressed and heat after this process, the air obtaining energy and momentum is discharged from propelling nozzle with the speed of up to 2000 feet per seconds (610 meter per second) or about 1400 miles per hours (2253 kilometers/hour).When high velocity spray air-flow ejection electromotor, drive compressor and turbine to continue to rotate simultaneously, maintain " cycle of operation ".The mechanical layout of turbogenerator is fairly simple, because it only comprises two main rotating parts, i.e. compressor and turbine, also one or several combustor.But, all aspects of the most this electromotor all have this simplicity, because heating power and Aerodynamic Problems are more complicated.These problems are by combustor and the elevated operating temperature of turbine, the air-flow being continually changing by compressor and turbo blade and to discharge the design work of combustion gas the gas extraction system that forms propulsion jet stream and cause.

When air speed is less than about 450 miles per hours (724 kilometers/hour), the efficiency of pure jet engine is less than the efficiency of propeller-type electromotor, because its propulsive efficiency depends greatly on its flight speed；Thus, pure turbojet is best suitable for higher flight speed.But, the flow perturbation caused due to the high tip speed of propeller, time more than 350 miles per hours (563 kilometers/hour), propeller efficiency reduces rapidly.These characteristics make aircraft that some medium speeds fly need not pure turbojet device and use the combination of propeller and gas-turbine unit--propjet.

The superiority of propeller/worm-gear combination is replaced by the introducing of bypass engine, ducted fan electromotor and propfan engine to a certain extent.Jet velocity is low than pure jet engine flow is big for these electromotors, thus, its propulsive efficiency is suitable with turboprop, has exceeded the propulsive efficiency of pure jet engine.

Turbojet (it is usually used in the Mach number various speed less than 3) is combined by turbine/ramjet with ramjet, has good performance when High Mach number.The surrounding of this electromotor is a duct, and front portion has variable geometry inlet, and rear portion is the afterburning jet pipe of band adjustable orifice.Take off and accelerate and under the state of flight of Mach number less than 3, the working method of the turbine jet engine that electromotor is conventional；When aircraft accelerates to Mach number more than 3, its turbojet mechanism is closed, and air flue air walks around compressor by means of guide vane, flows directly into afterburning jet pipe, and now this reinforcing jet pipe becomes the combustor of ramjet.This electromotor is suitable for requiring high-speed flight and maintaining the aircraft of High Mach number cruising condition, and under such conditions, this electromotor works in ramjet mode.

Understood by above, the raising of jet engine propulsive efficiency at present, it is all that the mechanism by turbine or propeller attracts large quantity of air to enter in jet engine, it is added significantly to the air capacity of the injection of jet engine, thus reduce jet velocity, because adding a little speed to large quantity of air or being provided that same thrust to one big speed of a small amount of air.Reduce jet velocity and can improve propulsive efficiency.But, current high efficiency jet engine, while improve propulsive efficiency, but causes that structure is complicated, resistance increases, material requirements is high, and processing technique is high and cost such as is significantly increased at the problem, brings the biggest impact also to the reliability of electromotor.

Summary of the invention

The purpose of the present invention is contemplated to overcome defect present in above-mentioned prior art, it is provided that the venturi jet engine that a kind of simple in construction, propulsive efficiency are high.

For reaching above-mentioned purpose, the concrete technical scheme that the present invention takes is as follows: the invention mainly comprises jet spray device, air diffusion chamber and nozzle, it it is the air diffusion chamber that internal diameter is bigger than jet spray device nozzle after jet spray device, with atmosphere between nozzle and the air diffusion chamber of jet spray device, the jet pipe of jet spray device afterbody ejects jet, air in air is produced Involving velocity, under Involving velocity, air around nozzle is pumped in air diffusion chamber, and from jet, obtain certain flow velocity, effluxvelocity declines the most therewith, the gas of big flow is spouting from nozzle, it is achieved thereby that the high efficiency spray regime of big flow low velocity, propulsive efficiency is greatly improved.This jet injection jet engine utilizing Venturi tube principle, has simple in construction, cost is low, reliability is high, propulsive efficiency advantages of higher.

Accompanying drawing explanation

Fig. 1 is the structural representation of venturi jet engine；

Fig. 2 is the two-stage tandem structural representation of venturi jet engine.

Fig. 3 is the venturi jet engine embodiment schematic diagram as the compressor of jet engine.

Detailed description of the invention

Below in conjunction with the accompanying drawings the present invention is further explained.

As shown in Figure 1, it it is the basic structure schematic diagram of the present invention, it is air diffusion chamber (3) after the nozzle (2) of jet spray device (1), the inlet inside diameter of air diffusion chamber (3) is bigger than the internal diameter of nozzle (2), between nozzle (2) and air diffusion chamber (3) from a distance, and and atmosphere.Jet spray device (1) sprays jet from nozzle (2), Involving velocity due to jet, ambient atmosphere is pumped in air diffusion chamber (3), from jet from obtaining certain flow velocity, spouting from nozzle (4) together with former jet.

As shown in Figure 2, it it is the two-stage tandem structural representation of the present invention, between first order air diffusion chamber (3) and second level air diffusion chamber (5) from a distance, again it is connected with air, from first order air diffusion chamber (3) jet out, spurt into second level air diffusion chamber (5), air produces bigger Involving velocity again to external world, more air enters in second level air diffusion chamber (5), and last large quantity of air sprays from nozzle (4).From structure, it is exactly substantially the basic structure series connection realization in the present invention, its objective is to increase the jet volume energy-absorbing power to air by tandem compound, improve the propulsive efficiency of venturi jet engine further.

As shown in Figure 3, it it is the present invention embodiment schematic diagram as the compressor of jet engine, venturi jet engine exists mainly as the compressor part of the air inflow of increase jet engine, jet engine (6) is the electromotors such as punching engine, it is positioned at the air diffusion chamber (5) of venturi jet engine, jet engine (6) afterbunring in big flow has the air stream of certain speed, jet is spouting from nozzle (4) together.

The present invention can also add the combinations such as parallel connection by the basic structure of venturi jet engine carries out plural serial stage or plural parallel stage or plural serial stage, further improve the Air entrainment of venturi jet engine, make spray air flow bigger and speed is lower, further improve propulsive efficiency.The mode that the present invention the most easily realizes is that the high temperature and high speed jet utilizing existing jet plane nozzle is as jet spray device, to this high temperature and high speed jet further with volume inspiration air mixed injecting, the propulsive efficiency of current jet plane the most also can be greatly improved.Jet engine air inlet can also utilize the present invention to Air Entrainment to improve air inflow.The high-speed jets such as plasma are efficiently utilized to realize it can in addition contain utilize.

Claims

1. a venturi jet engine, including jet spray device, air diffusion chamber and nozzle, it is characterised in that: penetrate It is air diffusion chamber after the nozzle of flow jet device, with atmosphere between nozzle and the air diffusion chamber of jet spray device, penetrates The jet pipe of flow jet device afterbody ejects jet, and the air in air produces Involving velocity, the air of volume inspiration and former jet Nozzle ejection from air diffusion chamber rear end together.

Venturi jet engine the most according to claim 1, is characterized in that: the nozzle inside diameter of jet spray device is than sky Gas diffusion chamber is little.

Venturi jet engine the most according to claim 1, is characterized in that: venturi jet engine can plural serial stage, Add parallel connection in parallel or series to improve propulsive efficiency.

Venturi jet engine the most according to claim 1, is characterized in that: venturi jet engine is placed in front end Use as compressor, it is also possible to be placed in rear end and advance use as jet engine.