Background technology
Colliery is one of important basic industries, is engaged in coal mining number more, in all kinds of mining industry, accounts for first place.Pneumoconiosis is the main occupational disease in colliery, and it not only affects the prodution and development of coal enterprise, and seriously jeopardizes people's health and lives.
To dust granules size and proportion, be divided into four instrumentation scopes at present: be greater than 10 microns; 5-10 microns; 2-5 microns; Be less than 2 microns.Wherein, to harm maximum, be 5 microns of following dust.In colliery, except the invisible dust larger to human injury, also exist a large amount of " floating dust ".
General spraying is not ideal to the effect of removal " respirable dust ", is mainly that particle diameter is between 200-600 microns because the particle diameter of water smoke is too large.From aerodynamic principle, thinner, close with dust size water smoke, optimal proportion is 0.8-1.3, more can effectively from air-flow, remove dust.Therefore, people update sprayer, so that water smoke sprays carefullyyer, are even less than the particle diameter of " respirable dust " particle.Yet, along with water smoke is more and more thinner, worry that water smoke will evaporate rapidly less than 100% space in relative temperature before capturing dust.
Existing atomizer is that employing is centrifugal or breaking mostly, also there is some scholars to study ultrasonic atomizatio, in commercial Application, they have advantage separately, but when having the colliery down-hole application of fire prevention, requirement of explosion proof, there is its limitation to be that centrifugal and breaking atomizer is all rotary sprayings, and under mine, dust concentration is higher, pollution is large, poor lubrication, dust falls into bearing with droplet, and rotating part very easily damages; Next is that the ultrasonic atomizing nozzle of industrial application is inverse piezoelectric effect, by alternating electric field, caused the mechanically deform of crystal, thereby generation acoustic vibration, by electric energy, change acoustic energy into, this ultrasonic atomizing nozzle structure can obtain very high audible frequency and acoustical power, but, for the mine of fire-proof and explosion-proof requirement, be but difficult to apply; The 3rd is that traditional atomizer water smoke particle diameter is large, undesirable to the seizure effect of respirable dust, and as easy as rolling off a logly at working face, forms ponding, and impact is normally produced.
Existing Hartmann oscillator is widely used industrial, as sound wave ashing, utilizes the effect of sound field energy, removes material superficial dust and is suspended in airborne dust; Ultrasonic atomizatio, utilizes the fluid whistle to produce ultrasonic wave and forms water smoke etc.The present invention is optimized for the tapered curve of Wei Duoxinsiji by the convergent mouth of gas whistle nozzle on the basis of Hartmann oscillator, to improve the phonation efficiency at the gas whistle, the vortex gas whistle has simple in structure in addition again, machinery-free moving component, without the advantage of power supply, a kind of fire prevention under coal mine and explosion-proof ultrasonic atomizing nozzle of being applicable to proposed.
Summary of the invention
Feature based on above-mentioned prior art and deficiency, also, in conjunction with colliery down-hole fireproof, the specific (special) requirements such as explosion-proof, the invention provides a kind of for the ultrasonic atomization dust-settling nozzle under coal mine.
A kind of for the ultrasonic atomization dust-settling nozzle under coal mine in order to realize, the measure that the present invention takes comprises that the vortex gas whistle of being fixed in nozzle body is linked with the gas whistle three parts, wherein:
The described vortex gas whistle be by inlet channel vertically along the tangential direction setting of cylindrical cavity and pass into cylindrical cavity, cylindrical cavity along cylindrical cavity axis be fixed on the Qi Shao nozzle UNICOM on nozzle body pedestal;
The described gas whistle is to consist of the gas whistle nozzle and the corresponding gas whistle resonator that is fixed on nozzle body top that are fixed on nozzle body bottom, and in periphery, the gas whistle, is provided with formation sonication range of atomization, nozzle body formation space;
Described nozzle body is to be arranged at the nozzle body cylindrical shell of periphery, the gas whistle and the nozzle body pedestal at the vortex gas whistle connects and composes, and be provided with water inlet in the nozzle body cylindrical shell bottom of periphery, the gas whistle, in top axis, be provided with adjusting bolt hole, in top side, end is provided with nozzle.
The described vortex gas whistle is " protruding " font structure, and its air intake duct and gas off-take diameter ratio are 2:1, and is provided with one section of external screw thread in the periphery of gas off-take, and for connecting gas whistle nozzle, air intake duct is connected on nozzle body pedestal; Described adjusting bolt is the spacing L that regulates gas whistle nozzle and gas whistle resonator
1, its adjustable range is 8 ~ 12mm;
Described gas whistle nozzle is the convergent mouth of the tapered curve of Wei Duoxinsiji, and its afterbody is provided with internal thread, is fixedly connected on nozzle body pedestal;
Described gas whistle resonator head is concave shaped, both sides chamfering, and afterbody fillet, and offer a screwed hole for regulating, be connected to the top of nozzle body cylindrical shell in central axis;
Described nozzle body cylindrical shell is offered a hole in central axis, and both sides chamfering offers conical nozzle hole at top side end, and afterbody offers four holes, for connecting the vortex gas whistle.
Provided by the present invention a kind of for the ultrasonic atomization dust-settling nozzle under coal mine, compared with prior art, its ultrasonic atomizing nozzle adopts air-flow acoustical generator, can not produce spark in installing and using process under coal mine, dependable performance while normally working, and cleaning is convenient; Adopt combined type ultrasonic atomizatio, the drop larger to diameter carries out secondary-atomizing, improved nebulization efficiency and power.Simultaneously according to the requirement to atomizing effect, by regulating the spacing of gas whistle nozzle and gas whistle resonator, variable spray patterns and the air saturation pattern of being changed to.
The specific embodiment
The specific embodiment of the present invention is further illustrated:
Implement the present invention a kind of for the ultrasonic atomization dust-settling nozzle under coal mine, be excessive for existing centrifugal, breaking spraying droplet diameter and utilize inverse piezoelectric effect to convert electrical energy into ultrasonic energy may to produce spark, to downhole safety, produce and bring hidden danger.The present invention proposes a kind of without friction means, without depositing dust ultrasonic atomizing nozzle under the coal mine of electricity or chemicals, to meet colliery down-hole fireproof, the special requirement such as explosion-proof.
The present invention adopts ultrasonic atomization dust-settling under coal mine, described ultrasonic wave has good directionality, reflectivity and penetration capacity, can in gas, liquid and solid medium, propagate, produce various ultrasonic effects, as mechanical effect, fuel factor, chemical effect, acoustic cavitation etc., ultrasonic wave also has the effect of seizure to fine dust.It is little that dust pelletizing system is taken up an area space simultaneously, can save the useful space; Compare with general deduster, ultrasonic atomizatio have reduce energy consumption, high efficiency, maintenance less, the feature such as expense is low.Therefore, using ultrasound technology carries out depositing dust and increases space humidity fine dust having under very strong operability and economic serviceability, particularly coal mine.
The present invention utilizes that ultrasonic atomizatio is theoretical, the principle at Hartmann oscillator and the vortex gas whistle, proposes ultrasonic atomization dust-settling nozzle under a kind of coal mine for depositing dust under coal mine, and its design principle is as follows:
Based on Lang formula d=0.34 (8 π γ/ρ f
2)
1/3, wherein: the diameter that d is water, the surface tension that γ is water, the density that ρ is water, f is supersonic frequency.Explanation changes under little coal mine at temperature and pressure, and the diameter of water droplets is inversely proportional to hyperacoustic frequency, that is to say that hyperacoustic frequency is higher, and the diameter of water droplets is less.In order to improve hyperacoustic frequency and acoustical power, the nozzle arrangements adopting is by the larger drop of one-level low-frequency ultrasonic atomizing, to be ejected into the atomization space at the secondary high frequency gas whistle, the drop that atomizing particle is larger will be further atomized into trickle droplet, according to mining face under mine environment, capable of regulating nozzle is spray patterns and air saturation pattern simultaneously.The design philosophy of its ultrasonic atomizing nozzle is as follows:
Adopt the vortex gas whistle 1, the described vortex gas whistle 1 consists of air intake duct, cylindrical cavity and gas off-take; Its air intake duct is along the tangential direction of cavity; Gas off-take is along the central axial direction of cavity.High-speed gas enters after cavity, along chamber wall fast rotational, produces vortex, and these rotating flows are radiated medium from outlet, then produce continuous pressure fluctuation with medium interaction, in time just produced sound wave.Its audible frequency theoretical relationship is: f=a (c/ π d) (p
1-p
2/ p
2)
1/2in formula, f is frequency, and a is less than 1 constant, and c is the velocity of sound, and d is cylindrical cavity diameter, p
1for inlet pressure, p
2for gas off-take pressure.
Adopt the gas whistle 2, the described gas whistle 2 is comprised of nozzle resonant cavity, in order to improve the phonation efficiency at the gas whistle, the convergent mouth at the gas whistle is designed to the tapered curve of Wei Duoxinsiji.When high-speed gas sprays from spray chamber, due to the sudden contraction in spray chamber cross section, can make the gas pressure before spray chamber present periodic variation.When high-speed gas enters resonator, in chamber, just produce gas replenishment process, and cause feedback flow to press rising gradually, recoil gas and incident gas collide mutually, on perpendicular to symmetry axis direction, form sonication.It is according to being according to the linear acoustic theory whistle frequency formula of must giving vent to anger for people such as Brocher that the theory of its audible frequency is calculated: f=c/4L, and wherein, c is the velocity of sound, L is the degree of depth of resonant cavity.From frequency formula, the audible frequency at the gas whistle is inversely proportional to the resonant cavity degree of depth, and by regulating adjusting nut 11 can change the degree of depth of resonant cavity, audible frequency also can change.
Below a kind of specific embodiment for the ultrasonic atomization dust-settling nozzle under coal mine provided by the present invention is further detailed:
For a ultrasonic atomization dust-settling nozzle under coal mine, comprise that the vortex gas whistle, the gas whistle and nozzle body three parts form, wherein:
The vortex gas whistle adopting consists of air intake duct, circular cylindrical cavity and gas off-take, gas off-take and air intake duct diameter ratio are 2:1, distance between air inlet passage center and gas off-take upper surface is 5 ~ 8 times of air intake duct diameter, its air intake duct along the tangential direction gas off-take of cavity along the axis direction of cavity.When high-speed gas enters cavity, along chamber wall fast rotary, transfer to produce vortex, rotary gas is radiated to medium from outlet, produces continuously pressure fluctuation with medium interaction, has just produced afterwards sound wave.The vortex gas whistle is simple in structure, movement-less part, and reliability is strong, and without electricity or the chemicals energy, unique to having advantages of under the high ground coal mine of fire prevention, requirement of explosion proof.But from the viewpoint of phonation efficiency etc., acoustical power output is not high with the ratio of inlet air flow power, and therefore, at the vortex gas whistle, gas off-take is connected in series a gas whistle.
The described gas whistle consists of nozzle resonant cavity, and the convergent mouth at its gas whistle is designed to the tapered curve of Wei Duoxinsiji, can effectively reduce the blockage effect to jet, improves phonation efficiency.High-speed gas enters the nozzle of the whistle from the ejection of vortex gas whistle gas off-take, due to the sudden contraction in spray chamber cross section, can make the gas pressure before spray chamber present periodic variation.When high-speed gas enters resonator, in chamber, just produce gas replenishment process, and cause feedback flow to press rising gradually, recoil gas and incident gas collide mutually, on perpendicular to symmetry axis direction, form sonication.Injection stream produces a compressional wave at humorous accent and propagates in chamber, then at the bottom of chamber, is reflected to accent place, is reflected once again generation compressional wave and propagates in chamber, forms high-frequency sound wave, and the water droplet that diameter is larger is further atomized into water droplet.
When needs are during to surrounding environment humidifying, the distance that can regulate the adjusting bolt 11 on nozzle body to change between the nozzle resonant cavity of the whistle, characteristic according to the whistle, audible frequency will change, theory by the ultrasonic atomizatio of Lang formula, fogdrop diameter will change along with the change of supersonic frequency, can reach thus the job requirement needing.
Embodiment 1
The gas off-take at the vortex gas whistle 5 adopts and is threaded with gas whistle nozzle 6, and the gas off-take screw thread at the vortex gas whistle 5 is screwed to the end of to.The resonator 7 at the gas whistle is connected by adjusting bolt 11 with nozzle body 8, is coated with last layer sizing material at the screw thread place of adjusting bolt 11 simultaneously, and adjusting bolt 11 and gas whistle resonator 7 is bonding in aggregates, and screw thread is screwed to the end.Then by nut 12 and bullet pad 13, coupled together with adjusting bolt 11, and nut 12 and bullet pad 13 glue is solid on nozzle body 8.The object of doing is like this consistent in order to guarantee the spacing of 7 of diameter and the gas whistle nozzle 6 of nozzle contraction mouth of gas whistle nozzle 6 and gas whistle resonators, to reach best atomizing effect; Because nut 12, bullet pad 13 form an integral body with nozzle body 8, by rotation adjusting bolt 11, can control the spacing of the resonator 7 at gas whistle nozzle 6, the gas whistle, according to the characteristic at the gas whistle, can change supersonic frequency, characteristic by ultrasonic atomizatio, the variation of frequency can cause the change of fogdrop diameter, has so just reached the adjustable object of atomizing effect.Complete after above-mentioned connection, nozzle body 8 is connected with the vortex gas whistle 5 use bolts.
When atomized dust settling, first by air intake duct 4, be communicated with compressed air, the pressure of gas is adjustable continuously between 0.2 ~ 0.5MPa, and the gentle whistle of nozzle body 8 nozzle 6, gas whistle resonator 7 are cleared up.Then by water inlet 9, connect static pressure water source, fine mist is sprayed by nozzle 10.
When needs are during to air saturation, by adjusting nut 11, distance between adjustable solar term whistle resonator 7 and gas whistle nozzle 6, according to the characteristic at the gas whistle, its audible frequency will change, by the characteristic of ultrasonic atomizatio, the diameter of droplet also will change, according to the requirement of site environment, suitably increase the flow of static pressure water, to reach the object of humidifying air.