Summary of the invention
The object of this invention is to provide fluid pressure monitoring system in a kind of closed container.This system can the pressure changing of liquid in periodic monitor closed container in real time, for a long time or as required, measurement result accurately, reliable; And which system reduces the working strength of staff, improve the intellectuality of fluid pressure monitoring and the work efficiency of monitoring, especially can be used for the dynamic monitoring of flammable and combustible liquids pressure in sealed shell of tank.
The present invention realizes the technical scheme that its goal of the invention takes: fluid pressure monitoring system in a kind of closed container, comprise front-end detection module, described front-end detection module is made up of the detection sub-module be mounted on each closed container outer wall, and its design feature is: the concrete structure of described each detection sub-module is:
Ultrasonic sensor: comprise and fit in transmitting probe on closed container outer wall and receiving transducer, for detecting the real-time pressure of liquid in closed container;
The radio-frequency (RF) tag be electrically connected with ultrasonic sensor and microcontroller one: the real-time pressure data of liquid in the closed container that ultrasonic sensor described in buffer storage records, and described pressure data is transferred to information transit module with radio frequency form;
Described information transit module is made up of multiple rotor module, and the concrete structure of described each rotor module is:
Frequency read/write: the real-time pressure data reading the radio-frequency (RF) tag of multiple detection sub-module within the scope of certain distance;
The microcontroller two be electrically connected with described frequency read/write: the pressure data that described frequency read/write reads is wirelessly transmitted to Monitoring and Controlling terminal;
Described Monitoring and Controlling terminal is connected with information transit module short-range wireless, for each rotor module work of control information transit module, receive, store the real-time pressure data that described rotor module sends, and to described pressure data information process analysis, judge the pressure state of closed container.
In the present invention, the pressure measuring principle of ultrasonic sensor is as follows:
For transmission-type ultrasonic sensor, as shown in Figure 2, transmitting probe and receiving transducer fit in the correspondence position on the relative outer wall of closed container respectively.During work, the transmitting probe of ultrasonic sensor launches ultrasonic longitudinal wave, and through being coupled into wall and the liquid medium of closed container, after different medium is propagated, received probe receives.
In figure, D, d are respectively closed container external diameter and internal diameter; δ is wall thickness, meets relational expression
δ=(D-d)/2(1)
The time that ultrasound wave is propagated at wall and liquid medium can be expressed as
t=t
s+t
m(2)
In formula, t
swith t
mrepresent that ultrasound wave is in wall, liquid medium travel-time respectively.T
swith t
mcan be obtained by formula (3), (4), t can be detected by sonac and obtain.
Wherein, v
srepresenting the velocity of propagation of ultrasound wave at outer wall, is known quantity; v
mrepresent that ultrasound wave can calculate with (4) in the velocity of propagation of liquid medium.
When first time pulse launched by ultrasonic pulse radiating circuit, propagation T.T. is t
1; The T.T. that second time transponder pulse is propagated is t
2.If the pressure of liquid medium changes, v will be caused
mchange, thus form the delay time difference Δ t in same ultrasonic wave propagation path.
Δt=t
1-t
2(5)
Therefore, pressure changes the sonic velocity change amount caused and can be expressed as
T in formula
1, t
2, t
s, d is known quantity, t
m1when representing that first time pulse launched by ultrasonic pulse radiating circuit, the time that ultrasound wave is propagated in liquid medium, t
m2when representing that second time pulse launched by ultrasonic pulse radiating circuit, the time that ultrasound wave is propagated in liquid medium.
In addition, ultrasonic compressional velocity of wave propagation is
Or
In formula: K is the elastic modulus of medium, relevant with medium pressure liquid; ρ is liquid medium density; γ is pressure-dependent coefficient.Obviously, known by formula (7), ultrasound wave velocity of propagation is in media as well relevant with elastic modulus with the density of liquid medium.The relation of pressure and sonic velocity change can be expressed as
In formula, v
0for the initial velocity of sound in ultrasound wave constant pressure liquid, draw by demarcating; Coefficient a
ican determine the demarcation of fluid to be measured.
Ultrasonic sensor can detect the time of twice ultrasonic pulse travels before and after pressure change in closed container, the mistiming Δ t of twice ultrasonic pulse travels can be extrapolated by formula (5), and then derived the velocity contrast v-v of twice ultrasonic pulse travels by formula (6)
0=Δ v, finally extrapolates liquid pressure value by formula (8).
Use the present invention to the step that fluid pressure in closed container is monitored is:
A, according to demarcating the liquid identical with testing liquid, obtain the relation curve of the pressure-ultrasonic velocity of testing liquid, and then according to the relation curve of pressure-ultrasonic velocity, the measurement parameter of setting ultrasonic sensor;
B, manipulation Monitoring and Controlling terminal, under Monitoring and Controlling terminal control, the controller two of the rotor module of described information transit module triggers frequency read/write and sends pumping signal;
After the radio-frequency (RF) tag excited target of the detection sub-module of C, described front-end detection module, start ultrasonic sensor work by microcontroller one, record the real-time pressure of liquid in closed container; Then the real-time pressure data that described ultrasonic sensor records is stored in radio-frequency (RF) tag by microcontroller one; Described real-time pressure data is passed to the frequency read/write of rotor module by radio-frequency (RF) tag again with radio frequency form;
The pressure data that described frequency read/write reads is wirelessly transmitted to Monitoring and Controlling terminal by the microcontroller two of D, described rotor module;
E, Monitoring and Controlling terminal receive, store the next real-time pressure data of described rotor module transmission, and to described pressure data Treatment Analysis, judge the pressure state of closed container.
Compared with prior art, the invention has the beneficial effects as follows:
One, adopt non-intervention type mode to measure fluid pressure in closed container, utilize the ultrasonic sensor fitted on closed container outer wall to measure the real-time pressure data of liquid in closed container, metering system is simple, and safety, monitoring accuracy is high, and cost is low.
Two, by arranging ultrasonic sensor on each closed container surface, then read and short-range wireless transmission through radio frequency successively, can simultaneously by the pressure of liquid in a collection of closed container of Monitoring and Controlling terminal monitoring.
Three, the present invention adopts wireless radio-frequency to transmit liquid real-time pressure data in closed container, cost is low, power consumption is few, each radio-frequency (RF) tag has unique sequence numbers, like this, as long as the sequence number recording radio-frequency (RF) tag just can be easy to determine the fluid pressure in the closed container corresponding to radio-frequency (RF) tag.
Four, after system installation, all operations are all completed by Monitoring and Controlling terminal, all pass through artificial installation, reduce the working strength of staff, reduce cost, improve work efficiency without the need to measuring at every turn.
Five, when not needing image data, front-end detection module, information transit module are all in " dormancy " state, can not cause the waste of electric energy, can ensure system long-time running, and need not frequently spend manpower and materials to safeguard.
Further, the transmitting probe of ultrasonic sensor of the present invention and receiving transducer are fitted on closed container outer wall by couplant.
Transmitting probe and receiving transducer not only can fit on closed container outer wall by couplant, also can get rid of the air between probe and container external box wall, ultrasonic wave energy is penetrated in closed container effectively, reduce ultrasonic hash, improve accuracy of detection.
Further, ultrasonic sensor of the present invention is transmission-type ultrasonic sensor, namely the transmitting probe of ultrasonic sensor fits in the correspondence position on the relative outer wall of closed container respectively with receiving transducer, and receiving transducer receives the ultrasonic signal transmitted through liquid in closed container that transmitting probe is launched.
Transmission-type ultrasonic sensor can avoid the ultrasound wave sound path that multiple reflections causes in a liquid to offset, and measurement result is more accurate.
Further, ultrasonic sensor of the present invention is used for the ultrasound wave of tracer liquid pressure is ultrasonic longitudinal wave.
Ultrasonic longitudinal wave can be propagated in solid and liquid medium, to fluid pressure sensitive.
Further, ultrasonic sensor of the present invention is used for the ultrasonic frequency range of tracer liquid pressure is 2 ~ 10MHz.
Prove through test, frequency range is that the ultrasound wave of 2 ~ 10MHz more easily obtains, and to fluid pressure sensitive, so use the ultrasound wave of said frequencies scope, testing result is accurate.
Further, the concrete mode that Monitoring and Controlling terminal of the present invention is connected with information transit module short-range wireless is: each rotor module of described Monitoring and Controlling terminal and information transit module is all provided with the low-power consumption monolithic radio frequency transceiving chip working in 2.4 ~ 2.4835GHz or 5.725 ~ 5.850GHz frequency band, in order to realize short-range wireless communication.
Monolithic radio frequency transceiving chip cost is low, and communication structure is simple, and communication speed is high, and communication is reliable, is easy to control and realize.
A preferred version of the present invention is, in described closed container, fluid pressure monitoring system also comprises remote monitoring center, described remote monitoring center and described Monitoring and Controlling terminal remote is wireless or wired connection, manipulation Monitoring and Controlling terminal works, the pressure data of liquid in the closed container that reception Monitoring and Controlling terminal stores; If force value has exceeded the boundary value preset, send early warning signal.
With above-mentioned preferred version of the present invention to the step that fluid pressure in closed container is monitored be:
A, according to demarcating the liquid identical with testing liquid, obtain the relation curve of the pressure-ultrasonic velocity of testing liquid, and then according to the relation curve of pressure-ultrasonic velocity, the measurement parameter of setting ultrasonic sensor;
B, by remote monitoring center manipulation Monitoring and Controlling terminal, under Monitoring and Controlling terminal control, the controller two of the rotor module of described information transit module triggers frequency read/write and sends pumping signal;
After the radio-frequency (RF) tag excited target of C, detection sub-module, ultrasonic sensor work is started by microcontroller one, record the real-time pressure of liquid in closed container, then the real-time pressure data that described ultrasonic sensor records is stored in radio-frequency (RF) tag by microcontroller one; Described real-time pressure data is passed to the frequency read/write of rotor module by radio-frequency (RF) tag again with radio frequency form;
The pressure data that described frequency read/write reads is wirelessly transmitted to Monitoring and Controlling terminal by the microcontroller two of D, described rotor module;
E, Monitoring and Controlling terminal receive, store the next real-time pressure data of described rotor module transmission, to described pressure data Treatment Analysis, judge the pressure state of closed container; And be sent to remote monitoring center by long-range for described pressure data.
Like this, can be controlled by remote monitoring center and monitor in warehouse or the real-time pressure data of liquid in closed container under other environment, removing Site Detection without the need to staff, improve job security and work efficiency.
Below in conjunction with the drawings and specific embodiments, the present invention is further described.
Embodiment
Embodiment one
Fig. 1, Fig. 2 and Fig. 3 illustrate, a kind of embodiment of the present invention is: fluid pressure monitoring system in a kind of closed container, comprise front-end detection module 1, described front-end detection module 1 is made up of the detection sub-module 1.0 be mounted on each closed container outer wall, and its design feature is: the concrete structure of described each detection sub-module 1.0 is:
Ultrasonic sensor 1.1: comprise and fit in transmitting probe 1.1a on closed container outer wall and receiving transducer 1.1b, for detecting the real-time pressure of liquid in closed container;
The radio-frequency (RF) tag 1.2 be electrically connected with ultrasonic sensor 1.1 and microcontroller 1: the real-time pressure data of liquid in the closed container that described in buffer storage, ultrasonic sensor 1.1 records, and described pressure data is transferred to information transit module 2 with radio frequency form;
Described information transit module 2 is made up of multiple rotor module 2.0, and the concrete structure of described each rotor module 2.0 is:
Frequency read/write 2.1: the real-time pressure data reading the radio-frequency (RF) tag 1.2 of multiple detection sub-module 1.0 within the scope of certain distance;
The microcontroller 2 2.2 be electrically connected with described frequency read/write 2.1: the pressure data that described frequency read/write 2.1 reads is wirelessly transmitted to Monitoring and Controlling terminal 3;
Described Monitoring and Controlling terminal 3 is connected with information transit module 2 short-range wireless, each rotor module 2.0 for control information transit module 2 works, receive, store the real-time pressure data that described rotor module 2.0 sends, and described processing data information is analyzed, judge the pressure state of closed container.
Transmitting probe 1.1a and the receiving transducer 1.1b of ultrasonic sensor 1.1 described in this example are fitted on closed container outer wall by couplant.
Ultrasonic sensor 1.1 described in this example is transmission-type ultrasonic sensor, namely the transmitting probe 1.1a of ultrasonic sensor 1.1 fits in the correspondence position on the relative outer wall of closed container 1.1 respectively with receiving transducer 1.1b, and receiving transducer 1.1b receives the ultrasonic signal transmitted through liquid in closed container that transmitting probe 1.1a launches.
Ultrasonic sensor 1.1 described in this example is ultrasonic longitudinal wave for detecting the ultrasound wave of fluid pressure in closed container.
Ultrasonic sensor 1.1 described in this example is 2 ~ 10MHz for detecting hyperacoustic frequency range of fluid pressure in closed container.
The concrete mode that the terminal of Monitoring and Controlling described in this example 3 is connected with information transit module 2 short-range wireless is: each rotor module 2.0 of described Monitoring and Controlling terminal 3 and information transit module 2 is all provided with the low-power consumption monolithic radio frequency transceiving chip working in 2.4 ~ 2.4835GHz or 5.725 ~ 5.850GHz frequency band, in order to realize short-range wireless communication.
As follows with the method step of fluid pressure monitoring system in above-mentioned closed container to fluid pressure monitoring in closed container:
A, according to demarcating the liquid identical with testing liquid, obtain the relation curve of the pressure-ultrasonic velocity of testing liquid, and then according to the relation curve of pressure-ultrasonic velocity, the measurement parameter of setting ultrasonic sensor 1.1;
B, manipulation Monitoring and Controlling terminal 3, under Monitoring and Controlling terminal 3 controls, the controller 2 2.2 of the rotor module 2.0 of information transit module 2 triggers frequency read/write 2.1 and sends pumping signal;
After radio-frequency (RF) tag 1.2 excited target of the detection sub-module 1.0 of C, front-end detection module 1, start ultrasonic sensor 1.1 by microcontroller 1 to work, record the real-time pressure of liquid in closed container, then the real-time pressure data that described ultrasonic sensor 1.1 records is stored in radio-frequency (RF) tag 1.2 by microcontroller 1; Described real-time pressure data is passed to the frequency read/write 2.1 of rotor module 2.0 by radio-frequency (RF) tag 1.2 again with radio frequency form;
The pressure data that described frequency read/write 2.1 reads is wirelessly transmitted to Monitoring and Controlling terminal 3 by the microcontroller 2 2.2 of D, described rotor module 2.0;
E, Monitoring and Controlling terminal 3 receive, store described rotor module 2.1 transmits next real-time pressure data, and to described pressure data Treatment Analysis, judges the pressure state of closed container.
Embodiment two
Fig. 4 illustrates, another embodiment of the invention is: fluid pressure monitoring system in a kind of closed container, comprise front-end detection module 1, described front-end detection module 1 is made up of the detection sub-module 1.0 be mounted on each closed container outer wall, and its design feature is: the concrete structure of described each detection sub-module 1.0 is:
Ultrasonic sensor 1.1: comprise and fit in transmitting probe 1.1a on closed container outer wall and receiving transducer 1.1b, for detecting the real-time pressure of liquid in closed container;
The radio-frequency (RF) tag 1.2 be electrically connected with ultrasonic sensor 1.1 and microcontroller 1: the real-time pressure data of liquid in the closed container that described in buffer storage, ultrasonic sensor 1.1 records, and described pressure data is transferred to information transit module 2 with radio frequency form;
Described information transit module 2 is made up of multiple rotor module 2.0, and the concrete structure of described each rotor module 2.0 is:
Frequency read/write 2.1: the real-time pressure data reading the radio-frequency (RF) tag 1.2 of multiple detection sub-module 1.0 within the scope of certain distance;
The microcontroller 2 2.2 be electrically connected with described frequency read/write 2.1: the pressure data that described frequency read/write 2.1 reads is wirelessly transmitted to Monitoring and Controlling terminal 3;
Described Monitoring and Controlling terminal 3 is connected with information transit module 2 short-range wireless, each rotor module 2.0 for control information transit module 2 works, receive, store the real-time pressure data that described rotor module 2.0 sends, and described processing data information is analyzed, judge the pressure state of closed container.
In closed container described in this example, fluid pressure monitoring system also comprises remote monitoring center 4, described remote monitoring center 4 and described Monitoring and Controlling terminal 3 long distance wireless or wired connection, manipulation Monitoring and Controlling terminal 3 works, the pressure data of liquid in the closed container that reception Monitoring and Controlling terminal 3 stores; If force value has exceeded the boundary value preset, send early warning signal.
Transmitting probe 1.1a and the receiving transducer 1.1b of ultrasonic sensor 1.1 described in this example are fitted on closed container outer wall by couplant.
Ultrasonic sensor 1.1 described in this example is transmission-type ultrasonic sensor, namely the transmitting probe 1.1a of ultrasonic sensor 1.1 fits in the correspondence position on the relative outer wall of closed container 1.1 respectively with receiving transducer 1.1b, and receiving transducer 1.1b receives the ultrasonic signal transmitted through liquid in closed container that transmitting probe 1.1a launches.
Ultrasonic sensor 1.1 described in this example is ultrasonic longitudinal wave for detecting the ultrasound wave of fluid pressure in closed container.
Ultrasonic sensor 1.1 described in this example is 2 ~ 10MHz for detecting hyperacoustic frequency range of fluid pressure in closed container.
The concrete mode that the terminal of Monitoring and Controlling described in this example 3 is connected with information transit module 2 short-range wireless is: each rotor module 2.0 of described Monitoring and Controlling terminal 3 and information transit module 2 is all provided with the low-power consumption monolithic radio frequency transceiving chip working in 2.4 ~ 2.4835GHz or 5.725 ~ 5.850GHz frequency band, in order to realize short-range wireless communication.
With the method step of fluid pressure monitoring system in above-mentioned closed container to fluid pressure monitoring in closed container be:
A, according to demarcating the liquid identical with testing liquid, obtain the relation curve of the pressure-ultrasonic velocity of testing liquid, and then according to the relation curve of pressure-ultrasonic velocity, the measurement parameter of setting ultrasonic sensor 1.1;
B, manipulate Monitoring and Controlling terminal 3 by remote monitoring center 4, under Monitoring and Controlling terminal 3 controls, the controller 2 2.2 of the rotor module 2.0 of information transit module 2 triggers frequency read/write 2.1 and sends pumping signal;
After radio-frequency (RF) tag 1.2 excited target of the detection sub-module 1.0 of C, front-end detection module 1, start ultrasonic sensor 1.1 by microcontroller 1 to work, record the real-time pressure of liquid in closed container, then the pressure data that described ultrasonic sensor 1.1 records is stored in radio-frequency (RF) tag 1.2 by microcontroller 1; Described real-time pressure data is passed to the frequency read/write 2.1 of rotor module 2.0 by radio-frequency (RF) tag 1.2 again with radio frequency form;
The pressure data that described frequency read/write 2.1 reads is wirelessly transmitted to Monitoring and Controlling terminal 3 by the microcontroller 2 2.2 of D, rotor module 2.0;
E, Monitoring and Controlling terminal 3 receive, store described rotor module 2.1 transmits next real-time pressure data, analyzes, judge the pressure state of closed container to described processing data information; And be sent to remote monitoring center 4 by long-range for described pressure data.
Embodiment three
This example is substantially identical with monitoring method with the monitoring system of embodiment one, different is only, ultrasonic sensor 1.1 described in this example is reflection-type ultrasonic sensor, namely the transmitting probe 1.1a of ultrasonic sensor 1.1 and receiving transducer 1.1b fits in the same position place on closed container 1.1 outer wall, or transmitting probe 1.1a and receiving transducer 1.1b is that (namely a probe is both as transmitting probe 1.1a for integral type structure, again as receiving transducer 1.1b), as shown in Figure 5.