CN102156086B - Method for measuring viscosity of dynamic fluid by using bending vibration - Google Patents

Abstract

The invention relates to a method for measuring viscosity, in particular to a method for measuring the viscosity of dynamic fluid by using a vibration pipe, a controller, a flow rate detecting device and a calculating device, wherein the vibration pipe is communicated with a fluid flow pipeline, the controller is used for controlling the vibration of the vibration pipe, and the flow rate detecting device and the calculating device are respectively arranged on two ends of the vibration pipe. Because a Coriolis mass flowmeter can be used for directly measuring the mass flow rate of the fluid, the dynamic viscosity measurement result with the flow rate compensated can be calculated conveniently, and further the viscosity of the fluid can be measured on line in real time. Because the Coriolis mass flowmeter can be used for measuring the density of the fluid in the pipe, the real-time kinematic viscosity of the fluid in the pipe can be obtained.

Description

A kind of method of utilizing flexural vibrations to measure dynamic fluid viscosity

[technical field]

The present invention relates to a kind of detection method of viscosity, relate in particular to a kind of detection method that detects dynamic fluid viscosity.

[background technology]

Viscosity and measurement thereof have in many fields of national economy more widely uses, for example in oil, chemical industry, traffic, national defence, light industry, food, building materials, coal, metallurgy, space flight, medicine and other fields.Viscosity measurement is the important means of production control flow process, assurance safety in production, control and evaluation product quality, medical diagnosis and scientific research.

Viscosity meter commonly used in the production procedure has capillary viscosimeter, rotary viscosimeter and oscillatory viscometer.

The capillary viscosimeter utilization be hage oiseuillelaw, by the record fall time of fluid in kapillary, calculate the viscosity of fluid, its shortcoming is to be difficult to realize industrial real-time online viscosity measurement, for example Chinese patent 200610041820.0.

Rotary viscosimeter mainly is to utilize by a synchronous micromotor drive rotating cylinder to rotate in detected fluid with certain speed, owing to be subject to the effect of fluid viscous power, rotating cylinder can produce hysteresis, the flexible member that is connected with rotating cylinder then can produce certain reversing in the opposite direction of rotation, just can calculate the viscosity number of fluid by the size of measuring distorting stress.But the shortcoming of the method is that required hardware device is more, needs to invade special device in the fluid, can not real-time online measuring.Chinese patent 96109032.4,01241517.0 for example.

Oscillatory viscometer mainly is to utilize special object to go deep in the measured fluid, be subject to the effect of fluid viscous power by measuring special object, the energy attenuation that causes realizes the measurement of viscosity, this method and rotary viscosimeter have a same shortcoming, must have exactly external object to invade in the fluid, and design is complicated.

Proposed a kind of fluid viscosity measuring method of static state in Chinese patent 200710018494.6, the implement device of the method is simple, and enters into fluid without the need for external object, has reduced some inconvenience of later stage measuring process.But simultaneously because this is a kind of fluid viscosity measuring method of static state, and the fluid in the commercial production often all flows, and is a kind of dynamic measurement, so the method can not realize industrial real-time online measuring function.

[summary of the invention]

The present invention aims to provide detection of dynamic, and result's a kind of method of utilizing flexural vibrations to measure dynamic fluid viscosity accurately.

Method of the present invention has been used the vibrating tube that is connected with liquid flow conduits, and the controller of control vibrating tube vibration is separately positioned on the flow detector that the vibrating tube two ends are located, and resolver; And the method may further comprise the steps:

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, and make fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously in the vibrating tube and treat fluid measured and make it inside to be full of this and to treat fluid measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, measure the output power P of this Time Controller and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously;

6. calculate the viscosity that this treats fluid measured,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

Wherein, step 1., 2., 4. with 5. in the amplitude of vibrating tube all identical.

Because coriolis mass flowmeters itself can directly be measured the mass rate of fluid, so the present invention can calculate the correction result of viscosity measurement very easily, thereby realizes the fluid viscosity real-time online measuring.And since coriolis mass flowmeters can the measuring tube inner fluid density, then can obtain simultaneously the real time kinematics viscosity of tube fluid.

[description of drawings]

Fig. 1: viscosity number is the dynamic measurement results of the silicone oil of 212mPas

Fig. 2: viscosity number is the dynamic measurement results of the silicone oil of 344mPas

Fig. 3: viscosity number is the dynamic measurement results of the silicone oil of 612mPas

Fig. 4: viscosity number is the dynamic measurement results of the lubricating oil of 107mPas

Fig. 5: viscosity number is the dynamic measurement results of the glycerine of 954mPas

Solid line is the practical viscosity of above-mentioned silicone oil or lubricating oil or glycerine among the figure, and round dot is measurement result of the present invention.

[embodiment]

Embodiment one

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude A, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude A, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude A, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously silicone oil to be measured (viscosity number is 212mPas) and make it inside in the vibrating tube and be full of this silicone oil to be measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude A, the output power P of Mersure Controler and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously; Horizontal survey is five times altogether;

6. calculate the viscosity of this silicone oil to be measured under each measurement result,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

7. testing result as shown in Figure 1.As shown in Figure 1, detection error of the present invention belongs in the admissible scope.

Embodiment two

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude B, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude B, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude B, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously silicone oil to be measured (viscosity number is 344mPas) and make it inside in the vibrating tube and be full of this silicone oil to be measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude B, the output power P of Mersure Controler and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously; Horizontal survey is five times altogether;

6. calculate the viscosity of this silicone oil to be measured under each measurement result,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

7. testing result as shown in Figure 2.As shown in Figure 2, detection error of the present invention belongs in the admissible scope.

Embodiment three

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude C, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude C, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude C, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously silicone oil to be measured (viscosity number is 612mPas) and make it inside in the vibrating tube and be full of this silicone oil to be measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude C, the output power P of Mersure Controler and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously; Horizontal survey is five times altogether;

6. calculate the viscosity of this silicone oil to be measured under each measurement result,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

7. testing result as shown in Figure 3.As shown in Figure 3, detection error of the present invention belongs in the admissible scope.

Embodiment four

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control is carried out the flexural vibrations of the permanent width of cloth with amplitude D vibrating tube, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude D, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude D, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously lubricating oil to be measured (viscosity number is 107mPas) and make it inside in the vibrating tube and be full of this lubricating oil to be measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude D, the output power P of Mersure Controler and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously; Horizontal survey is five times altogether;

6. calculate this oil body to be measured under each measurement result,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

7. testing result as shown in Figure 4.As shown in Figure 4, detection error of the present invention belongs in the admissible scope.

Embodiment five

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude E, the output power P of measuring vibrations tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude E, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude E, the output power P of Mersure Controler ₂Resonance frequency f with vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously glycerine to be measured (viscosity number is 954mPas) and make it inside in the vibrating tube and be full of this glycerine to be measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth with amplitude E, the output power P of Mersure Controler and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously; Horizontal survey is five times altogether;

6. calculate the viscosity of this glycerine to be measured under each measurement result,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

7. testing result as shown in Figure 5.As shown in Figure 5, detection error of the present invention belongs in the admissible scope.

Claims (2)

1. method of utilizing flexural vibrations to measure dynamic fluid viscosity, the method has been used the vibrating tube that is connected with liquid flow conduits, and the controller of control vibrating tube vibration is separately positioned on the flow detector at place, vibrating tube two ends and resolver; It is characterized in that the method may further comprise the steps:

1. inject continuously air and make it inside in the vibrating tube and be full of air, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, guarantee passing in the situation of liquid of the same race, each driving of measuring is by the output power P of control survey vibrating tube vibration Time Controller ₀Resonance frequency f with vibrating tube ₀

2. in vibrating tube, inject continuously known kinetic viscosity η ₁Fluid and make it inside and be full of this fluid, and make fluid in the pipe not have axial flow velocity along duct orientation, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, the output power P of Mersure Controler ₁Resonance frequency f with vibrating tube ₁

3. Fluid Computation viscous force factor K _s

$K_s=\frac{{\mathrm{\η}}_1{f}_1}{(\frac{P_1}{f_1}-\frac{P_0}{f_0})}$

4. in vibrating tube, inject continuously known quality flow Q ₁Fluid and make it inside and be full of this fluid, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, the output power P2 of Mersure Controler and the resonance frequency f of vibrating tube ₂, and calculate the coriolis force Energy consumption factor K of this fluid _c,

$K_c=\frac{K_s}{Q_1{f}_2}(\frac{P_2}{f_2}-\frac{P_1}{f_1})$

5. inject continuously in the vibrating tube and treat fluid measured and make it inside to be full of this and to treat fluid measured, controller control vibrating tube is carried out the flexural vibrations of the permanent width of cloth, measure the output power P of this Time Controller and the resonance frequency f of vibrating tube, flow detector is measured the real-time mass rate Q of this moment simultaneously;

6. calculate the viscosity that this treats fluid measured,

$\mathrm{\η}=\frac{K_s}{f}(\frac{P}{f}-\frac{P_0}{f_0})-K_{c}Q$

Wherein, step 1., 2., 4. with 5. in the amplitude of vibrating tube all identical.

2. the method for claim 1 is characterized in that the vibrating tube entrance and exit also is respectively equipped with a solenoid valve, is carrying out step 2. before the described measurement, and shut electromagnetic valve makes fluid in the pipe not have axial flow velocity along duct orientation.

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