CN201082829Y - Air quantity and wind pressure binary equilibrium equipment - Google Patents

Abstract

The utility model relates to an air output and pressure binary balancer, which comprises a driver fixed in a casing. An air admission silencer is arranged on the external surface of the air admission end of the casing, a tapered air outlet end is communicated with a connecting air pipe after passing through a pneumatic valve, and a conducting wire connector for receiving an air flow signal and a pressure signal in an air force system pipe is arranged on the pneumatic valve; the driver is arranged at the air admission end of the casing, the power output end of the driver is connected with a sliding rod, and an elastic spiral piece is arranged on the sliding rod; the problems of the broken ratio of the material and the physical component difference, etc. during the transportation process can be effectively reduced through the device, the material consumption is reduced, and the inward quality uniformity of the product is improved. The difficult problem that the replacing load air output and the air pressure are simultaneously controlled and set, thus the utility model has strong practicability, and can be widely used for a variety of multi-branch pipe and low vacuum sucking type physical distribution systems. The utility model has remarkable effect to balance and stabilize the production, reduce the material consumption, improve the quality of the product, thus having greater technical economic value.

Description

Air quantity, blast binary decision tree device

Technical field

The utility model relates to a kind ofly can control and regulate the air quantity Q that enters air-flow in the wind power system pipe and air quantity, the blast binary decision tree device of blast P simultaneously.

Technical background

1, the conveying of negative pressure dilute phase strength is that a class provides energy by blower fan, the diffusing shape solids of certain unit weight and granularity is transported to the feedway of desired location with carrier gas stream.This device often is made of a plurality of branch roads.Pressing fluid forms the liquid motion in it to be divided and makes two parts: 1. mass transport section; 2. air return section.It in 1. the gas-solid two-phase movement; State of kinematic motion depends primarily on carrier gas stream.Be dusty gas motion in 2., because of this dustiness under the normal circumstances little, so can be considered general gasmovement.Because negative pressure dilute phase delivery air speed must satisfy transported material suspension fluidizing velocity, so flow velocity is higher, general 8～10m/s＜v＜50m/s makes its reynolds number Re＞2000, is to be turbulent flow.Aborning, the physics of transported material, chemical index are process stipulations, even the temperature of production environment, humidity are all manually set; Perhaps external environment condition disturbing factor such as temperature Change etc. have been excluded, and delivery pipe and outside no interchange of heat are so actual condition can be considered isothermal, adiabatic motion.During engineering was used, the factor of influence and EVAC (Evacuation Network Computer Model) fluid movement was also a lot, no matter but how complicated its state of kinematic motion is, and all must follow mass conservation law is that continuity equation, conservation of energy theorem are that Bernou1li equation, the law of conservation of momentum are momentum equation.

Equalization stable is industrial basic demand, and characteristics and engineering applicable cases according to above-mentioned negative pressure dilute phase delivery system have good reason to prove, air quantity Q, blast P are two topmost parameters.Q, P can be effectively controlled, just the system equalization smooth running can be made.

2, valve is a modal device in the engineering fluid motion, and kind and form are too numerous to enumerate.To liquid, its flow pressure can obtain than accuracy control; But to gas, situation is just much complicated.Because gas has compressibility, Q, P two amounts are closely related, but parameter is too many, and when air flow stream during to valve region, the fluidised form sudden turn of events is very complicated disturbed flow condition, so that does not still have practical and effective math modeling and respective function relation so far in the world.Therefore, lack feasible clear and definite corresponding control relation between the aperture of valve and gas flow (flow velocity) and the pressure, can only do approximate fuzzy the adjusting with change of fluid.Quite a lot of to the steady flow situation, but air-flow is also in continuous variation in system, and when being the disturbed flow condition of obvious fluctuation, the relation of valve opening and gas flow, pressure is difficult to determine especially, can't support the dynamic demand for control when air quantity Q, blast P have clear and definite controlled numerical value.So so far, also there is not to carry out Q, the P of air-flow simultaneously the integrated valve of dynamic quantitative control.

3, to the multiple branch circuit negative-pressure pneumatic transmission system of a balanced smooth running of design, an arm dams suddenly if having arbitrarily when operation, and all the other arm flows in operation are increased.And the quantity of intercepting sewer is many more, influences greatly more, and reason is:

Cause: ρ ₁V ₁A ₁=ρ ₂V ₂A ₃-continuity equation

$Q=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{Q}_i(m^3/h)$

$V_i=\frac{Q_i}{A_{i\×3600}}(m/s)$

Selected and operating mode one timing when blower fan, Q=C (constant), this moment, establishing respectively, the amount of damming was Δ Q if there is any m branch road to dam suddenly _iThen: $\mathrm{\ΔQ}=\stackrel{m}{\mathrm{\Σ}}\mathrm{\Δ}{Q}_i.$ The flow that remains in each arm of work will increase, and be made as Q _i'

$Q=\underset{i=1}{\overset{n-m}{\mathrm{\Σ}}}{Q}_i^{\′}=\underset{i=1}{\overset{n-m}{\mathrm{\Σ}}}{\stackrel{i=1}{Q}}_i+\underset{i=1}{\overset{m}{\mathrm{\Σ}}}\mathrm{\Δ}{Q}_i$

If each arm fluidised form equates in the system, Q is arranged just _i=Q ₀(fixed number), Q _i'=Q ₀' (fixed number), Δ Q _i=Δ Q _i' (fixed number), so: $Q=\underset{.i=1}{\overset{n}{\mathrm{\Σ}}}{Q}_i=n\·Q_0$

Q ₀＝(n-m)Q ₀

Obviously: n＞(n-m), so V '＞V ₀Residue work airduct wind speed is greater than former wind speed.Example: as blower fan stream Q=15000m ³/ h, Φ=150mm arm is the n=12 root altogether, makes each tube section equate, impedance equates that promptly wind speed equates. calculate when damming suddenly m respectively ₁=1, m ₂=3, m ₃=5, m ₄=7 o'clock, the wind speed of residue work arm, when m gets different value, result of calculation such as following table

As seen from the above table, several m that dam have significant impact to system's wind speed, and m is big more, and the wind speed increment is big more, and when m＞n/2, system has been tending towards and can not have normally moved.

The fact is, arbitrarily after the damming of m arm, not only causes the variation of air quantity in the system, also will cause the variation of blast, the system pipe network characteristic changed, and then have influence on the variation of blower fan operating characteristic, and situation is very complicated.Under this kind state, the valve regulated ability on the arm will increase and is tending towards losing efficacy with m.

Just get an inference thus: since the operating mode that exists any m of a ccasual arm to dam suddenly, make the system airflow play suddenly fluctuate, and residue work arm valve regulating power is limited, even be tending towards losing efficacy, the most succinct actv. way that the system that keeps does not so fluctuate is exactly: when the amount of damming takes place, mend an equivalence immediately and substitute amount.

4, at the system airflow big ups and downs of damming and causing, now existing a lot of engineerings have been used the person in charge or each return air arm and have been carried out corresponding method of mending wind, and have received certain effect, but not as one wishes to the greatest extent yet.Investigate further and analyze, found the problem place: wind is mended in existing bypass, only is to have installed air valve on pipeline additional, does corresponding the keying according to the signal that dams.Owing to this benefit air-valve directly communicates with atmosphere, very little along journey resistance damage, and theory all confirms with testing.Guaranteeing that permission by determining that flow Q gets under the condition, produces to such an extent that local resistance is very limited by valve, be significantly less than overall drag at the switching point conveying pipeline.Know by engineering fluid mechanics:

$P_1=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{p}_{l}i=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{s}_i\·Q_i^2$ P ₁-lose along the journey overall drag

P ₁=∑ pf+ ∑ pm S _iThe impedance of-airduct

Have: $Q_i\∝\frac{1}{\sqrt{S_i}}$ The Q-flow.

By last explanation, the root of mean square of flow and airduct impedance is inversely proportional to, and flow will distribute by this rule in the parallel pipeline system, and its arm flow that impedance is big is little, and little its arm flow of impedance is big.

Since the defeated straight tube of expecting arm of each in the system by equivalent length, formations such as adapter bonnet, valve, and have Dual-Phrase Distribution of Gas olid, its comprehensive impedance S ₁Value is not little; And the benefit wind bypass impedance value that only is made of very short front and back connection pipe and valve will be very limited, so S must be arranged ₁＞S ₂, even S ₁＞＞S ₂Situation.

After damming, when mending wind, at this moment because of mending wind bypass impedance S ₂＜S ₁, and less than the impedance S of arbitrary work arm _i, its flow Q that from system, has been assigned to then ₂Must be greater than former working flow Q ₁Be Q ₂＞Q ₁Obvious, this mends into amount is limited to the effect of system stability.

This has just illustrated why only mend the also unfavorable reason of wind mode effect with simply joining valve.Effectively mend the wind balance, also must solve and mend the problem that bypass impedance must equate with the work branch impedance.

The utility model content

The utility model provides a kind of air quantity, blast binary decision tree device, be applicable in manifold series connection and parallel vacuum dilute phase air-transport system, any n the arm that dams at random done equivalent substituting of moment, to eliminate, keep system's inner fluid smooth running all the time because of arm the dam system airflow that causes and the big ups and downs of logistics.

The utility model reaches by following technical measures: a kind of air quantity, blast binary decision tree device, it is characterized in that: an actuator that is fixed in the casing is arranged, the inlet end outside face of casing is equipped with intake muffler, the taper outlet side behind a pneumatic valve be connected airduct UNICOM, the conductor interface of accepting airflow signal and pressure signal in the wind power system pipe is arranged on the pneumatic valve; Actuator is installed in the inlet end of casing by bracing frame, and the clutch end of actuator connects a sliding bar, and the elastic helix sheet is housed on the sliding bar.

Described pneumatic valve is positioned in the outlet of taper outlet side of casing.

There is a streamlined reefer housing described actuator outside.

The utility model has been eliminated the manifold negative-pressure pneumatic transmission system substantially because of the system airflow big ups and downs situation that any m arm dams at random and cause, and makes to be transferred material constant speed, smooth and easy conveying relatively.Thus, can effectively reduce the problems such as broken, physics component difference of making of material in the course of conveying, material consumption is reduced, product interior quality conformability improves.Efficiently solve control simultaneously and set the knotty problem that substitutes load air quantity, blast, very strong practicality is arranged, can be widely used in all kinds of manifold low vacuum suctions and send the formula logistics system.Quality to equalization stable production, reduction material consumption, raising product has remarkable effect, thereby has bigger Technological Economy value.

Description of drawings

Fig. 1 is a structural principle scheme drawing of the present utility model.

Fig. 2 is an adjustable resistance principle schematic of the present utility model.

The specific embodiment

As shown in the figure, the utility model has an actuator 2 that is fixed in the casing 1, and there is a streamlined reefer housing 3 the actuator outside.The inlet end outside face of casing is equipped with intake muffler 4, taper outlet side 8 behind a pneumatic valve 9 be connected airduct 10 UNICOMs, pneumatic valve is connected with pressure signal by the interior airflow signal of electrical lead interface 11 and wind power system pipe; Actuator is installed in the inlet end of casing by bracing frame 5 in housing, the clutch end of actuator is connected with sliding bar 6, and elastic helix sheet 7 is housed on the sliding bar.Along air flow line, when ambient air entered casing, helical pitch was t ₁, to the angle of facining the wind being arranged or being called helixangle ₁, under the guide functions of flight, air-flow is pressed helixangle ₁Screw motion has obtained the resistance P of local disturbance _m, and formed simulated impedance S jointly with various local resistances and on-way resistance ₁When making the flight helical pitch, actuator becomes t ₂The time, corresponding helical angle is θ ₂, in like manner obtain simulated impedance S ₂

Because actuator can make the elastic helix sheet make continuous dislocation, therefore can obtain continually varying impedance S _x

When helical pitch t changed, resistance is index to be changed.Under this structure, although very big variation has taken place resistance, it is less to record the flowrate variation slope at front end, and so just switching is closed and suitable flow regulating provides condition in order only to do with valve.The adjusting here is a kind of static adjusting, is a quiescent operation that makes analog quantity approach the amount of damming as far as possible.

Working process:

According to flow parameter behind near conveying pipeline system design or the on-the-spot test acquisition switching point, determine the analog quantity basic specification as calculated.Choose the spiral number that suitable diameter D, helical pitch count m, elastic helix sheet, and reserve helical pitch t up-down adjustment amount, i.e. P _mPositive and negative regulated quantity.After matching appropriate diameter pneumatic valve, binary decision tree device structure is promptly formed in assembling.Finished product binary decision tree device is done the simulated impedance test at test cell, and does corresponding demarcation.Behind the on-site installation, carrying out fine tuning by system mainly is to regulate S, and checks actual mend tolerance, blast, locking then.

During work, the conductor interface of pneumatic valve and unit discharge valve are made simple switch amount interlocking.When the unit discharge valve cuts out, that is after the signal that dams sends, gas is endeavoured valve and is opened immediately, and in response time t≤1 second, the equivalent air-flow that substitutes is mended immediately into system; Otherwise, when discharge valve is opened, open the stream signal and instruct gulp valve to close at once.Process is very simple, reliable.

Because the wind speed that negative pressure dilute phase strength is carried is higher, when mending into air-flow in moment, admission port can produce noise, is provided with intake muffler specially for this reason.Outer cover is housed on the actuator, and the housing inlet end has end plate can prevent effectively that foreign matter from sucking the harm system.After actuator is mixed controller, can realize Long-distance Control.

Claims (3)

1. an air quantity, blast binary decision tree device, it is characterized in that: an actuator that is fixed in the casing is arranged, the inlet end outside face of casing is equipped with intake muffler, the taper outlet side behind a pneumatic valve be connected airduct UNICOM, the conductor interface of accepting airflow signal and pressure signal in the wind power system pipe is arranged on the pneumatic valve; Actuator is installed in the inlet end of casing by bracing frame, and the clutch end of actuator connects a sliding bar, and the elastic helix sheet is housed on the sliding bar.

2. air quantity according to claim 1, blast binary decision tree device is characterized in that: described pneumatic valve is positioned in the outlet of taper outlet side of casing.

3. air quantity according to claim 1, blast binary decision tree device is characterized in that: there is a streamlined reefer housing described actuator outside.

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