阅读说明：本技术 一种220Rn子体状态参数的调控装置及调控方法 (A kind of220Rn daughter state parameter regulation and control device and regulation and control method ) 是由 吕丽丹 何正忠 肖德涛 蔺健 于 2021-09-09 设计创作，主要内容包括：本发明涉及一种～(220)Rn子体状态参数的调控装置及调控方法,控制器根据状态参数与待调参数之间的关系,通过调节待调参数将～(220)Rn子体室的状态参数调节至目标值,待调参数包括充源回路的第一换气速率以及补充回路的第二换气速率和/或气溶胶浓度,进而通过调节换气速率和气溶胶浓度,实现～(220)Rn子体室中～(220)Rn子体状态参数的稳定调控,并且在调节结束后,充源回路按照第一换气速率进行工作,持续向～(220)Rn子体室内输入～(220)Rn子体,补充回路按照第二换气速率和气溶胶浓度进行工作,持续向～(220)Rn子体室内补充物质,始终使状态参数稳定在目标值。(The invention relates to a 220 The controller adjusts the parameters to be adjusted according to the relationship between the state parameters and the parameters to be adjusted 220 Adjusting the state parameters of the Rn daughter chamber to a target value, wherein the parameters to be adjusted comprise a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit, and further realizing the purpose of adjusting the ventilation rate and the aerosol concentration 220 Rn daughter chamber 220 Stably regulating and controlling the state parameters of the Rn daughter, and after regulation is finished, the charging circuit works according to a first ventilation rate continuously 220 Rn daughter indoor input 220 Rn daughter, the replenishment circuit operating at a second aeration rate and aerosol concentration, continuing to 220 And supplementing substances into the Rn daughter chamber to always stabilize the state parameters at the target values.)

1. A kind of²²⁰Rn daughter State parameterThe regulating device is characterized by comprising a controller,²²⁰The Rn daughter chamber, the source charging loop and the supplement loop;

the controller is respectively in communication connection with the charging source loop and the supplementary loop; both ends of the charging circuit and both ends of the supplementary circuit are connected with the²²⁰The Rn daughter chambers are connected;

the controller is used for adjusting the parameters to be adjusted according to the relation between the state parameters and the parameters to be adjusted²²⁰Adjusting the state parameters of the Rn daughter chamber to target values; the state parameters comprise²²⁰Rn daughter concentration, unbound fraction, and daughter activity ratio; the parameter to be adjusted comprises a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit;

the charging circuit is used for working according to the first ventilation rate and continuously supplying air to the charging circuit²²⁰Rn daughter indoor input²²⁰An Rn daughter; the supplementary loop is used for continuously working according to the second ventilation rate and the aerosol concentration²²⁰And supplementing substances into the Rn daughter chamber.

2. The regulation device of claim 1 wherein the charging circuit comprises a first constant flow pump,²²⁰An Rn source and an air filter; one end of the first constant flow pump and²²⁰the Rn daughter chambers are connected, and the other end of the first constant flow pump is connected with the²²⁰One end of the Rn source is connected; the above-mentioned²²⁰The other end of the Rn source is connected with one end of the air filter; the other end of the air filter is connected with the air filter²²⁰The Rn daughter chambers are connected;

the first constant flow pump is used for ventilating at the first ventilation rate²²⁰Extracting air flow from the Rn daughter chamber; the above-mentioned²²⁰The Rn source is used for generating under the action of the airflow²²⁰Rn, and reacting said²²⁰Rn is input to the air filter through the air filter²²⁰And an Rn daughter chamber.

3. The regulation device of claim 1 wherein the make-up circuit comprises an air make-up branch and an aerosol make-up branch;

the controller is used for judging whether the target value is needed to be changed or not according to the target value²²⁰Supplementing aerosol indoors by the Rn daughter, controlling the air supplementing branch circuit to work when the aerosol does not need to be supplemented, and controlling the aerosol supplementing branch circuit to work when the aerosol needs to be supplemented;

the air supplement branch is used for working according to the second air change rate to the air supplement branch²²⁰Filtering the substances in the Rn daughter chamber;

the aerosol supplementary branch circuit is used for working according to the second ventilation rate and the aerosol concentration and supplying the aerosol to the air conditioner²²⁰And supplementing aerosol in the Rn daughter chamber.

4. The regulation device of claim 3 wherein the air make-up branch comprises a second constant flow pump, a first gas three-way valve, a second gas three-way valve, and an air filter; one end of the second constant flow pump and²²⁰the Rn daughter chambers are connected, and the other end of the second constant flow pump is connected with the first end of the first gas three-way valve; the second end of the first gas three-way valve is connected with the first end of the second gas three-way valve; the second end of the second gas three-way valve is connected with one end of the air filter; the other end of the air filter is connected with the air filter²²⁰The Rn daughter chambers are connected;

the second constant flow pump is used for ventilating at the second ventilation rate²²⁰Extracting gas flow from the Rn daughter chamber, and inputting the gas flow to the air filter through the first gas three-way valve and the second gas three-way valve; the air filter is used for filtering the air flow to obtain filtered air, and inputting the filtered air to the air filter²²⁰And an Rn daughter chamber.

5. A regulating device according to claim 3, characterized in thatThe aerosol supplementing branch comprises a second constant flow pump, a first gas three-way valve and an aerosol diluting chamber; one end of the second constant flow pump and²²⁰the Rn daughter chambers are connected, and the other end of the second constant flow pump is connected with the first end of the first gas three-way valve; the third end of the first gas three-way valve is connected with one end of the aerosol diluting chamber; the other end of the aerosol diluting chamber is connected with the aerosol diluting chamber²²⁰The Rn daughter chambers are connected;

the second constant flow pump is used for ventilating at the second ventilation rate²²⁰Extracting air flow from the Rn daughter chamber, and inputting the air flow into the aerosol dilution chamber through the first gas three-way valve; the aerosol diluting chamber is internally stored with aerosol and is used for supplying the aerosol to the aerosol diluting chamber under the action of the airflow²²⁰And aerosol is input into the Rn daughter chamber.

6. The regulation device of claim 1, further comprising an analog sampling loop; the analog sampling loop comprises a sampling pump, a second gas three-way valve and an air filter; one end of the sampling pump and²²⁰the Rn daughter chamber is connected, and the other end of the sampling pump is connected with a third end of the second gas three-way valve; the second end of the second gas three-way valve is connected with one end of the air filter, and the other end of the air filter is connected with the air filter²²⁰The Rn daughter chambers are connected;

the controller is used for adjusting the second ventilation rate of the supplementary circuit while controlling the analog sampling circuit to work, so that the adjusted ventilation rate of the supplementary circuit is equal to the difference between the second ventilation rate and the third ventilation rate of the analog sampling circuit;

the sampling pump is configured to remove the third ventilation rate from the sample chamber²²⁰Extracting gas flow from the Rn daughter chamber, and inputting the gas flow to the air filter through the second gas three-way valve; the air filter is used for filtering the air flow to obtain filtered air and inputting the filtered air into the air filterTo the above²²⁰And an Rn daughter chamber.

7. The regulation device of claim 6, wherein a sampling device is coupled to the sampling pump inlet for sampling a sub-volume in the gas stream at a rate less than the third air exchange rate.

8. A kind of²²⁰The regulation and control method of the state parameters of the Rn daughter is characterized by comprising the following steps:

judging whether the state parameter needs to be changed according to the target value of the state parameter²²⁰Supplementing aerosol into the Rn daughter chamber to obtain a first judgment result;

when the first judgment result is yes, adjusting a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit, and carrying out the steps²²⁰Adjusting the state parameters of the Rn daughter chamber to target values;

when the first judgment result is negative, adjusting a first air exchange rate of the charging source circuit and a second air exchange rate of the supplementary circuit, and enabling the charging source circuit and the supplementary circuit to be in a state of being in a negative state²²⁰The state parameter of the Rn daughter chamber is adjusted to a target value.

9. A modulation and control method according to claim 8, wherein adjusting the aerosol concentration specifically comprises:

and the aerosol concentration of the supplementary circuit is regulated by regulating the interval time of inputting the aerosol into the aerosol dilution chamber by the aerosol generator and the flow rate of the third constant flow pump.

10. The method of claim 8, wherein adjusting the first air exchange rate of the charging circuit and the second air exchange rate of the supplemental circuit specifically comprises:

adjusting a first ventilation rate of the charging circuit by adjusting a flow rate of a first constant flow pump;

the second ventilation rate of the supplemental circuit is adjusted by adjusting a flow rate of a second constant flow pump.

Technical Field

The invention relates to²²⁰Rn daughter state parameter regulation and control technology field, in particular to²²⁰An adjusting device and an adjusting method for multiple state parameters of an Rn daughter.

Background

China is a high thorium background area and a large rare earth producing country, and the environment and the rare earth development and production process are not ignored²²⁰Rn and²²⁰rn daughterExposing the hazard.²²⁰The half-life of Rn is short,²²⁰rn hazards mainly originate from²²⁰And (7) an Rn daughter. Accurate evaluation²²⁰Rn daughter exposure hazards need to be developed under various typical environmental conditions²²⁰Rn daughter concentration, fraction of unbound state, daughter activity ratio (²¹²Bi/²¹²Pb), and the like. For this purpose, it is necessary to establish conditions that enable different typical environmental conditions to be achieved²²⁰The metering device for regulating and controlling the state parameters such as Rn daughter concentration, unbound state share, daughter activity ratio and the like meets the requirement of²²⁰Rn daughter state parameter measurement method and instrument scale calibration requirement, and monitoring site is ensured²²⁰The reliability of the data of Rn daughter concentration, fraction of unbound state and daughter activity ratio.

At present, established²²⁰Rn chambers are mostly aimed at²²⁰And regulating and controlling the Rn concentration. The general disadvantages are: has been established²²⁰Rn indoor²²⁰The Rn daughter is mainly in a binding state due to²²⁰The deposition rate of the Rn daughter in an unbound state is higher than that of the Rn daughter in an bound state by more than one order of magnitude²²⁰Rn daughter is easier to deposit on the wall, so that the pair²²⁰The stable regulation of the unbound state of Rn daughter is difficult to realize and the difference is not satisfied²²⁰The stable regulation and control of the state parameters of the Rn daughter cannot realize full simulation and reproduction of typical environmental conditions. Therefore, it is necessary to establish a stable adjustment²²⁰The Rn daughter state parameter regulating and controlling device solves the problems and meets the requirement of metering scales.

Disclosure of Invention

The invention aims to provide²²⁰The regulation and control device and the regulation and control method of the state parameters of the Rn daughter can realize²²⁰Stable regulation of Rn daughter state parameters to meet²²⁰Rn daughter measurement and instrument calibration requirements.

In order to achieve the purpose, the invention provides the following scheme:

a kind of²²⁰The regulation and control device for the state parameters of the Rn daughter comprises a controller,²²⁰The Rn daughter chamber, the source charging loop and the supplement loop;

the controller is respectively in communication connection with the charging source loop and the supplementary loop; both ends of the charging circuit and both ends of the supplementary circuit are connected with the²²⁰The Rn daughter chambers are connected;

the controller is used for adjusting the parameters to be adjusted according to the relation between the state parameters and the parameters to be adjusted²²⁰Adjusting the state parameters of the Rn daughter chamber to target values; the state parameters comprise²²⁰Rn daughter concentration, unbound fraction, and daughter activity ratio; the parameter to be adjusted comprises a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit;

the charging circuit is used for working according to the first ventilation rate and continuously supplying air to the charging circuit²²⁰Rn daughter indoor input²²⁰An Rn daughter; the supplementary loop is used for continuously working according to the second ventilation rate and the aerosol concentration²²⁰And supplementing substances into the Rn daughter chamber.

In another aspect, the present invention is directed to providing a method²²⁰The regulation and control method of the state parameters of the Rn daughter comprises the following steps:

judging whether the state parameter needs to be changed according to the target value of the state parameter²²⁰Supplementing aerosol into the Rn daughter chamber to obtain a first judgment result;

when the first judgment result is yes, adjusting a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit, and carrying out the steps²²⁰Adjusting the state parameters of the Rn daughter chamber to target values;

when the first judgment result is negative, adjusting a first air exchange rate of the charging source circuit and a second air exchange rate of the supplementary circuit, and enabling the charging source circuit and the supplementary circuit to be in a state of being in a negative state²²⁰The state parameter of the Rn daughter chamber is adjusted to a target value.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

the invention is used for providing²²⁰The Rn daughter state parameter regulating device and method includes that the controller is used for regulating the state parameter of the Rn daughter and the parameter to be regulatedBy adjusting the parameters to be adjusted²²⁰Adjusting the state parameters of the Rn daughter chamber to a target value, wherein the parameters to be adjusted comprise a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit, and further realizing the purpose of adjusting the ventilation rate and the aerosol concentration²²⁰Rn daughter chamber²²⁰And stably regulating and controlling the state parameters of the Rn daughter. And after the regulation is finished, the charging circuit works according to the first ventilation rate continuously²²⁰Rn daughter indoor input²²⁰Rn daughter, the replenishment circuit operating at a second aeration rate and aerosol concentration, continuing to²²⁰Rn daughter chamber is supplemented with substances, and then establishment of²²⁰Rn daughter chamber²²⁰And the dynamic balance between the Rn daughter compensation and the loss always stabilizes the state parameter at the target value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a regulation device provided in embodiment 1 of the present invention.

Fig. 2 is a flowchart of a method of the regulation method provided in embodiment 2 of the present invention.

Description of the symbols:

1-a first constant flow pump; 2-²²⁰An Rn source; 3-an air filter; 4-a second gas three-way valve; 5-a sampling pump; 6-²²⁰An Rn daughter chamber; 7-a second constant flow pump; 8-aerosol dilution chamber; 9-a third constant flow pump; 10-an aerosol filter; 11-aerosol particle size spectrometer; 12-an aerosol generator; 13-silica gel connecting pipe; 14-first gas three-way valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide²²⁰The regulation and control device and the regulation and control method of the state parameters of the Rn daughter can realize²²⁰Stable regulation of Rn daughter state parameters to meet²²⁰And (4) measuring state parameters of the Rn daughter and measuring instrument scales.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Example 1:

to realize²²⁰The stable regulation and control of the state parameters of the Rn daughters needs to predetermine parameters to be regulated which influence the state parameters. Therefore, before describing the control device used in this embodiment, the following steps are performed²¹²For example, the regulation mode of Pb (ThB) daughter is to determine the parameters to be regulated which affect the state parameters. In the regulation of ThB daughter, ThB is composed entirely of²²⁰Rn source charging²²⁰In Rn daughter chamber²²⁰Rn emanates from the gas decay and, taking into account the decay, coanda, deposition and ventilation losses of ThB itself,²²⁰the change in concentration of ThB daughter in the Rn daughter chamber can be described by the following first order differential equation.²²⁰Activity concentration C of unbound ThB in Rn daughter chamber^f _ThB(the unit is Bq. m)^-3) The rate of change of (d) is:

in the formula (1), lambda_ThBIs the decay constant of ThB, and has a value of 0.065h^-1；Is in an unbound state²¹⁶Activity concentration of Po (ThA) (in Bq. m)^-3) (ii) a The daughter in X form is combined with the aerosolThe binding rate of (a), which is a function related to aerosol particle size and concentration; v. of_aIs composed of²²⁰Total ventilation rate of Rn daughter chamber; v is²²⁰Volume of Rn daughter chamber, m³；The deposition coanda ratio is for unbound state ThB.

In that²²⁰At daughter concentration equilibrium in the Rn daughter chamber, equation (1) becomes:

in the formula (2), χ is calculated as follows:

in the formula (3), D_fThe diffusion coefficient of unbound state daughter; v. of₀The average thermal movement rate of the unbound state daughter in the air; d is the aerosol particle size; delta₀＝(d/2)+L₀，L₀Is the mean free path of unbound state daughter; n (d) is the aerosol concentration.

²²⁰The half-life of ThA in Rn daughter is only 0.15s, the decay constant lambda of ThA_ThAIs 16632h^-1Much larger than the deposition and purging rates, so that the deposition and purging losses of ThA are negligible. The concentration of unbound ThA can be determined by equation (4):

in the formula (4), C_TnIs composed of²²⁰Thorium emanation in the Rn daughter chamber (²²⁰Rn) concentration.

Activity concentration of ThB daughter in bound stateThe formula is as follows:

in the formula (5), the reaction mixture is,the deposition coanda ratio is the combined state ThB.

Then the stable concentration C of ThB_ThBComprises the following steps:

fraction f of unbound state of ThB_ThBComprises the following steps:

equation (4) — (7) establishes the relationship between ThB stable concentration and unbound fraction and related variables.

Assuming that the behavioral properties of ThC daughter are the same as those of ThB, the activity concentration of the unbound state of ThC can be obtainedActivity concentration in binding state to ThCThe expression of (a) is:

in formula (8), λ_ThCIs the decay constant of ThC;the deposition mura ratio of the unbound ThC.

In the formula (9), the reaction mixture is,the deposition coanda ratio for the combined state ThC.

Fraction f of unbound state according to ThC_ThCBy determining the fraction f of unbound state of ThC_ThC：

The concentration of ThC unbound daughter in the environment is very low and negligible relative to the concentration of ThC unbound daughter, and therefore, the expressions for the activity ratio between the unbound ThC and ThB and the bound ThC and ThB can be determined from the following equations (4), (5), (8) and (9):

as can be seen from the above formula, in²²⁰When the concentration of Rn is constant,²²⁰the influence factors of Rn daughter concentration, unbound state fraction and ThC/ThB activity ratio include aerosol concentration, aerosol particle size,²²⁰Rn daughter coanda rate and ventilation rate, wherein aerosol concentration and ventilation rate are easily adjusted and controlled. By stably controlling two influencing factors of aerosol concentration and air exchange rate, the method can ensure²²⁰And the state parameters of the Rn daughter stably run for a long time.

Based on this conclusion, the present embodiment is configured to provide a method²²⁰An Rn daughter status parameter regulating device, as shown in FIG. 1, comprising a controller,²²⁰Rn daughter chamber 6, source charging circuitAnd a supplementary circuit for supplying the liquid to the tank,²²⁰the volume of the Rn daughter chamber 6 may be 0.443m³. The controller is respectively in communication connection with the charging source loop and the supplementary loop, and both ends of the charging source loop and both ends of the supplementary loop are respectively connected with²²⁰The Rn daughter chambers 6 are connected.

The controller is used for adjusting the parameters to be adjusted according to the relation between the state parameters and the parameters to be adjusted, namely according to the formula (7), the formula (10), the formula (11) and the formula (12)²²⁰The state parameters of the Rn daughter chamber 6 are adjusted to target values. The state parameters include²²⁰Rn daughter concentration, unbound fraction, and daughter activity ratio. The parameters to be adjusted include a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplemental circuit. Since the total ventilation rate is the sum of the first ventilation rate of the charging circuit and the second ventilation rate of the supplemental circuit, this is achieved by adjusting the first ventilation rate and the second ventilation rate when adjusting the total ventilation rate. Due to the fact that²²⁰The Rn daughter concentration is mainly related to the first air exchange rate of the charging circuit, so that the first air exchange rate is adjusted to realize²²⁰The stable regulation and control of the Rn daughter concentration and good regulation²²⁰After the Rn daughter concentration, the second ventilation rate and/or the aerosol concentration of the supplemental circuit is adjusted according to formula (7), formula (10), formula (11), and formula (12) to establish the aerosol concentration and the ventilation rate and²²⁰functional relationship between state parameters of Rn daughter chamber 6 such that²²⁰The regulation and control of the unconjugated state share of the Rn daughter chamber 6 and the activity ratio of ThC/ThB are quantified, and the regulation becomes convenient, quick and reliable. By the concentration of the aerosol,²²⁰The stable regulation and control of the total ventilation rate of the Rn daughter chamber 6 can be realized²²⁰And stably regulating and controlling state parameters in the Rn daughter chamber 6.

The charging circuit is used for working according to a first ventilation rate and continuously supplying²²⁰Rn daughter chamber 6 internal input²²⁰Rn, thereby generating²²⁰And (7) an Rn daughter. The supplementary loop is used for operating according to the second ventilation rate and the aerosol concentration continuously²²⁰And the Rn daughter chamber 6 is supplemented with substances. After the parameters to be adjusted are adjusted, the charging circuit and the supplementary circuit work according to the adjusted parameters, and the charging circuit and the supplementary circuit can be used for adjusting the parameters to be adjusted²²⁰The state parameters of the Rn daughter chamber 6 are always maintained at the target values to realize²²⁰Dynamic equilibrium of state parameters of the Rn daughter chamber 6.

Specifically, the charging circuit of the present embodiment includes a first constant current pump 1,²²⁰Rn source 2 and air filter 3, the first constant flow pump 1 can be a low flow rate constant flow pump,²²⁰rn source 2 may be a gas flow type solid²²⁰Rn source, the air filter 3 may be a high efficiency filter. One end of the first constant flow pump 1 and²²⁰the Rn daughter chamber 6 is connected with the other end of the first constant flow pump 1²²⁰One end of the Rn source 2 is connected,²²⁰the other end of the Rn source 2 is connected with one end of an air filter 3, and the other end of the air filter 3 is connected with²²⁰The Rn daughter chambers 6 are connected. Namely a first constant flow pump 1,²²⁰Rn source 2 and air filter 3 are connected in sequence, and then two ends are respectively connected with²²⁰And the Rn daughter chambers 6 are connected to form a closed-loop charging circuit. The first constant flow pump 1 is adapted to move from a first ventilation rate to a second ventilation rate²²⁰The Rn daughter chamber 6 draws a gas flow through it at a first aeration rate²²⁰The source (2) of the radio (Rn),²²⁰rn source 2 is used for generating under the action of airflow²²⁰Rn, and²²⁰rn is input through an air filter 3 to²²⁰Rn daughter chamber 6, constituting a closed circuit, in which²²⁰Establishing a high and stable concentration of Rn daughter in the chamber 6²²⁰And (7) an Rn daughter.

The replenishment circuit of the present embodiment includes an air replenishment branch and an aerosol replenishment branch. The controller is used for judging whether the direction of the target value is needed²²⁰And aerosol is supplemented in the Rn daughter chamber 6, the air supplement branch is controlled to work when the aerosol is not required to be supplemented, and the aerosol supplement branch is controlled to work when the aerosol is required to be supplemented. Specifically, the controller is controlled in such a way that a switch K1 is arranged on the air supplement branch, switches K2 and K3 are arranged on the aerosol supplement branch, and when the air supplement branch needs to be switched to²²⁰When the aerosol is supplemented in the Rn daughter chamber 6, the controller controls K1 to be closed, and controls K2 and K3 to be opened at the same time, so that the aerosol supplementing branch is put into operation. In the direction of no need²²⁰When the aerosol is supplemented in the Rn daughter chamber 6, the controller controls K1 to be opened and controls K2 and K3 to be closed simultaneously, so that the air is supplemented to the branchAnd putting into operation. The air supplement branch is used for working according to a second air exchange rate and continuously filtering²²⁰Daughter in Rn daughter chamber 6 and aerosol. The aerosol supplement branch is used for working according to a second ventilation rate and aerosol concentration²²⁰And the Rn daughter chamber 6 is supplemented with aerosol.

Further, the air supplement branch includes a second constant flow pump 7, a first gas three-way valve 14, a second gas three-way valve 4, and an air filter 3. One end of the second constant flow pump 7 and²²⁰rn daughter chamber 6 is connected, the other end of second constant flow pump 7 is connected with the first end of first gas three-way valve 14, the second end of first gas three-way valve 14 is connected with the first end of second gas three-way valve 4, the second end of second gas three-way valve 4 is connected with one end of air cleaner 3, the other end of air cleaner 3 and the first end of second gas three-way valve 4 are connected²²⁰The Rn daughter chambers 6 are connected. A second constant flow pump 7 for pumping air at a second air exchange rate²²⁰And extracting gas flow from the Rn daughter chamber 6, and inputting the gas flow to the air filter 3 through the first gas three-way valve 14 and the second gas three-way valve 4. The air filter 3 being for use in the air flow²²⁰Filtering the Rn daughter and the aerosol to obtain filtered air, and inputting the filtered air to²²⁰And an Rn daughter chamber 6.

The aerosol supplement branch comprises a second constant flow pump 7, a first gas three-way valve 14 and an aerosol dilution chamber 8. One end of the second constant flow pump 7 and²²⁰rn daughter chamber 6 is connected, and the other end of second constant flow pump 7 is connected with the first end of first gas three-way valve 14, and the third end of first gas three-way valve 14 is connected with the one end of aerosol dilution chamber 8, and the other end of aerosol dilution chamber 8 and the first end of aerosol dilution chamber 14 are connected²²⁰The Rn daughter chambers 6 are connected. A second constant flow pump 7 for pumping air at a second air exchange rate²²⁰And extracting gas flow from the Rn daughter chamber 6, and inputting the gas flow into the aerosol diluting chamber 8 through a first gas three-way valve 14. The aerosol diluting chamber 8 stores the aerosol, and the aerosol diluting chamber 8 is used for downwards moving under the action of the airflow²²⁰Aerosol is input into the Rn daughter chamber 6.

Based on the specific structure of the aerosol supplement branch and the air supplement branch, the working process of the supplement loop is as follows: when it is not neededTo the direction of²²⁰When the Rn daughter chamber 6 is filled with aerosol, the switch K1 is opened, the switches K2 and K3 are both disconnected, and the second constant flow pump 7 supplies air to the room at a second air exchange rate²²⁰The Rn daughter chamber 6 extracts the airflow and leads back to the first gas three-way valve 14, the second gas three-way valve 4 and the air filter 3²²⁰And a closed loop circulation is formed in the Rn daughter chamber 6. When needed, the direction of the water flow is changed²²⁰When the Rn daughter chamber 6 is filled with aerosol, the switch K1 is turned off, the switches K2 and K3 are both turned on, and the second constant flow pump 7 supplies air to the room at a second air exchange rate²²⁰The Rn daughter chamber 6 draws air flow and enters the aerosol diluting chamber 8 through the first air three-way valve 14²²⁰The pressure difference between the Rn daughter chamber 6 and the aerosol diluting chamber 8 can make the aerosol in the aerosol diluting chamber 8 enter through the silica gel connecting pipe 13²²⁰And an Rn daughter chamber 6, which forms a closed loop.

It should be noted that the aerosol dilution chamber 8 may have a volume of 2.7m³The silica gel connecting tube 13 is used to realize the aerosol diluting chamber 8 and²²⁰the connection between Rn daughter chambers 6, the switch K1 may be disposed between the first gas three-way valve 14 and the second gas three-way valve 4, the switch K2 may be disposed between the first gas three-way valve 14 and the aerosol dilution chamber 8, and the switch K3 may be disposed on the silica gel connection pipe 13.

In addition, the regulating device of the present embodiment further includes an aerosol generator 12, and the aerosol generator 12 may use a coherent monodisperse aerosol generator manufactured by TSI corporation of america. The aerosol generator 12 is communicated with the aerosol diluting chamber 8, and the aerosol generator 12 supplies aerosol into the aerosol diluting chamber 8 at equal time intervals. The embodiment further comprises an aerosol dilution circuit, the aerosol dilution circuit comprises an aerosol dilution chamber 8, an aerosol filter 10 and a third constant flow pump 9, the aerosol dilution chamber 8, the aerosol filter 10 and the third constant flow pump 9 form a closed circuit, the third constant flow pump 9 is used for drawing airflow to the aerosol dilution chamber 8, and the aerosol filter 10 is used for filtering aerosol in the airflow to dilute the aerosol in the aerosol dilution chamber 8. The present embodiment controls the time interval for the aerosol generator 12 to replenish the aerosol into the aerosol dilution chamber 8 and the flow rate of the third constant flow pump 9Adjusting the concentration of the aerosol in the aerosol dilution chamber 8 such that²²⁰The aerosol concentration in the Rn daughter chamber 6 was stable at different levels. The aerosol dilution circuit is arranged to dilute the high-concentration aerosol generated by the aerosol generator 12, avoid large fluctuation of the aerosol concentration and realize²²⁰And stably regulating and controlling the monodisperse aerosol in the low concentration range in the Rn daughter chamber 6.

Based on the specific structure of the charging circuit and the supplementary circuit, the charging circuit of the present embodiment²²⁰Rn source 2 generated²²⁰Rn is continuously sent into the constant flow pump 1²²⁰Rn daughter chamber 6, such that²²⁰In Rn daughter chamber 6²²⁰Rn daughter was growing continuously and air make-up branch extraction in make-up loop²²⁰The airflow of the Rn daughter chamber 6 is injected again through the air filter 3²²⁰Rn daughter chamber 6, such that²²⁰In Rn daughter chamber 6²²⁰Rn daughter is continuously lost, and then stable work of the charging circuit and the supplementary circuit is adopted to ensure that²²⁰Rn daughter chamber 6²²⁰Rn daughter growth and loss reach a balance, and can be established²²⁰Rn daughter chamber 6²²⁰Dynamic balance between Rn daughter compensation and loss to avoid²²⁰Rn daughter chamber 6²²⁰An accumulation process of more than three days required for the Rn daughter concentration to reestablish equilibrium. When the aerosol needs to be supplemented, the aerosol supplementing branch in the supplementing loop continuously feeds to²²⁰The Rn daughter chamber 6 is supplemented with aerosol, and the process of extracting air flow of the air supplement branch in the charging loop and the supplement loop reduces the aerosol concentration at a stable speed, so that the aerosol concentration can be matched with the air supplement branch²²⁰The aerosol concentration in the Rn daughter chamber 6 establishes equilibrium due to the supplemental growth.

The large-flow sampling or long-time sampling of the scale instrument is very easy to cause²²⁰Rn daughter chamber 6²²⁰The change of the state of Rn daughter aerosol makes the Rn daughter originally in stable concentration²²⁰The fraction of unbound state of Rn daughter decreases continuously and²²⁰change of the Rn daughter activity ratio. In order to solve this problem, the control device of this embodiment further includes an analog sampling loop. The analog sampling loop comprises a sampling pump 5 and a second gas three-way valve4 and an air filter 3. One end of the sampling pump 5 is connected with²²⁰Rn daughter chamber 6 is connected, and the other end of sampling pump 5 is connected with the third end of second gas three-way valve 4, and the second end of second gas three-way valve 4 is connected with air cleaner 3's one end, air cleaner 3's the other end and air cleaner 3's one end²²⁰The Rn daughter chambers 6 are connected. In order to avoid the influence on the state parameter when the analog sampling loop is used for sampling, the controller is used for adjusting the second ventilation rate of the supplementary loop while controlling the analog sampling loop to work, so that the adjusted ventilation rate of the supplementary loop is equal to the difference between the second ventilation rate and the third ventilation rate of the analog sampling loop. The sampling pump 5 is used for collecting the air at a third air exchange rate²²⁰The Rn daughter chamber 6 draws air flow and inputs the air flow to the air filter 3 through the second air three-way valve 4, and the air filter 3 is used for aerosol in the air flow and aerosol in the air flow²²⁰Filtering the Rn daughter to obtain filtered air, and inputting the filtered air to²²⁰And an Rn daughter chamber 6.

Specifically, when sampling with the analog sampling loop, the inlet of the sampling pump 5 is directly connected to a sampling device for sampling the daughter in the gas stream at a rate less than the third air exchange rate. Furthermore, during sampling, the air flow pumped by the sampling pump 5 is guided back to the second air three-way valve 4 and the air filter 3 at a third air exchange rate²²⁰A closed loop circulation is formed in the Rn daughter chamber 6, the third ventilation rate is ensured to be stable no matter whether sampling is carried out or not, and the sampling is prevented from causing²²⁰The concentration state of the neutron body in the Rn daughter chamber 6 is changed. By setting an analog sampling loop, the method makes²²⁰Daughter in Rn daughter chamber 6 is lost at a constant rate, eliminating²²⁰Daughter sampling during application of Rn daughter chamber 6 results²²⁰The unstable state parameters of Rn daughter and the gas path makes²²⁰The Rn daughter chamber 6 has certain airflow flow and can be realized without stirring by a fan²²⁰Rn daughters are uniformly distributed, and the tradition is avoided²²⁰Rn chamber using fan belt²²⁰And the Rn daughter state parameters are difficult to realize stable control.

As an optional implementation manner, the regulating device of this embodiment further includesAn aerosol particle size spectrometer 11, the aerosol particle size spectrometer 11 being respectively connected with²²⁰Rn daughter chamber 6 is communicated with aerosol diluting chamber 8, and a switch K4 is arranged on a connecting loop of aerosol particle size spectrometer 11 and aerosol diluting chamber 8, and the switch K4 is arranged between aerosol particle size spectrometer 11 and aerosol diluting chamber 8²²⁰And a switch K5 is arranged on the connecting loop of the Rn daughter chamber 6. By the controller opening the relevant switch, can be paired²²⁰The aerosol concentration and particle size in the Rn daughter chamber 6 or the aerosol dilution chamber 8 are analyzed. The aerosol particle size spectrometer 11 may use a nanoscale aerosol particle size spectrometer manufactured by TSI corporation of america to monitor the concentration and particle size distribution of the aerosol.

In the embodiment, the analog sampling loop is opened when sampling is needed, the ventilation rate of the supplement loop is adjusted, and sampling is performed at the third ventilation rate which is less than that of the analog sampling loop after the analog sampling loop is opened, so that the influence of the sampling process on the state parameters can be avoided. Of course, the present embodiment may also set the analog sampling circuit to be always on, and adjust the state parameter by adjusting the first ventilation rate of the charging circuit, the second ventilation rate and/or aerosol concentration of the supplemental circuit, and the third ventilation rate of the analog sampling circuit. Meanwhile, during sampling, sampling is carried out at a third ventilation rate which is less than that of the analog sampling loop, so that the influence of the sampling process on the state parameters can be avoided.

The embodiment relates to²²⁰Rn daughter metering device²²⁰Rn daughter state parameter control technology, especially convenient and fast implementation²²⁰And the state parameters of the Rn daughter are stably regulated and controlled so as to meet the requirements of a state parameter measuring method and instrument scales. The aerosol concentration in the aerosol diluting chamber 8 is adjusted by changing the interval time of inputting the aerosol into the aerosol diluting chamber 8 by the aerosol generator 12 and the flow rate of the third constant flow pump 9, so as to adjust²²⁰Rn daughter chamber 6 aerosol concentration, recombination changes²²⁰The total air exchange rate of the Rn chamber can be adjusted and controlled to be different²²⁰Rn daughter stable concentration, unbound fraction, ThC/ThB activity ratio, etc²²⁰And (3) realizing stable regulation and control of the state parameters of the Rn daughter.

Example 2:

the embodiment is used for providing²²⁰The method for regulating and controlling the state parameters of the Rn daughter controls the regulation and control device described in embodiment 1 to work, as shown in fig. 2, the regulation and control method includes:

s1: judging whether the state parameter needs to be changed according to the target value of the state parameter²²⁰Supplementing aerosol into the Rn daughter chamber to obtain a first judgment result;

s2: when the first judgment result is yes, adjusting a first ventilation rate of the charging circuit and a second ventilation rate and/or aerosol concentration of the supplementary circuit, and carrying out the steps²²⁰Adjusting the state parameters of the Rn daughter chamber to target values;

s3: when the first judgment result is negative, adjusting a first air exchange rate of the charging source circuit and a second air exchange rate of the supplementary circuit, and enabling the charging source circuit and the supplementary circuit to be in a state of being in a negative state²²⁰The state parameter of the Rn daughter chamber is adjusted to a target value.

Specifically, adjusting the aerosol concentration may include: the aerosol concentration in the aerosol dilution chamber 8 is adjusted by adjusting the interval of time the aerosol generator 12 inputs aerosol into the aerosol dilution chamber 8 to adjust the aerosol input rate and by adjusting the flow rate of the third constant flow pump 9 to adjust the rate of aerosol filtration loss in the aerosol dilution chamber 8.

Adjusting the first ventilation rate of the charging circuit and the second ventilation rate of the supplemental circuit specifically includes: adjusting a first ventilation rate of the charging circuit by adjusting a flow rate of the first constant flow pump; a second ventilation rate of the supplemental circuit is adjusted by adjusting a flow rate of the second constant flow pump.

When the analog sampling circuit is always opened, the regulation and control method of the embodiment adjusts the first ventilation rate of the charging circuit, the second ventilation rate and/or aerosol concentration of the supplement circuit and the third ventilation rate of the analog sampling circuit after obtaining the first judgment result, and when the first judgment result is yes, the regulation and control method adjusts the first ventilation rate of the charging circuit, the second ventilation rate and/or aerosol concentration of the supplement circuit and the third ventilation rate of the analog sampling circuit, so that the analog sampling circuit is always opened²²⁰The state parameter of the Rn daughter chamber is adjusted to a target value. When the first judgment result is negative, adjusting the first ventilation rate of the charging circuit, the second ventilation rate of the supplementary circuit and the third ventilation of the analog sampling circuitRate of change of²²⁰The state parameter of the Rn daughter chamber is adjusted to a target value.

The specific regulation and control method comprises the following steps: with flow rates less than 5 L.min^-1At a first ventilation rate V₁Extraction of²²⁰Thorium emanation generated by Rn source (²²⁰Rn) and input to²²⁰And an Rn daughter chamber. When aerosol is not required to be injected, the switch K1 is opened, the K2 and the K3 are both disconnected, the analog sampling loop driven by the sampling pump at the third ventilation rate and the air supplement branch driven by the second constant flow pump at the second ventilation rate are connected in parallel through the second air three-way valve, and the sampling loop and the air supplement branch are enabled to pass through the air filter²²⁰Indoor of Rn daughter²²⁰The concentration of Rn daughter and aerosol is continuously lost. When the aerosol needs to be injected, the switch K1 is switched off, the switches K2 and K3 are both switched on, the aerosol supplementary branch driven by the second constant flow pump at the second ventilation rate enters the aerosol diluting chamber, and the aerosol supplementary branch is driven by the second constant flow pump at the second ventilation rate to enter the aerosol diluting chamber²²⁰The aerosol in the aerosol diluting chamber enters through the silica gel connecting pipe due to the pressure difference between the Rn daughter chamber and the aerosol diluting chamber²²⁰Rn daughter chamber, so that the aerosol dilutes the chamber with²²⁰The aerosol concentration in the Rn daughter chamber reaches a stable dynamic equilibrium. And (3) equivalently supplementing aerosol into the aerosol diluting chamber at equal time intervals by using an aerosol generator, adjusting different levels of aerosol concentration in the aerosol diluting chamber by adjusting the interval time and the speed of a third constant flow pump in an aerosol diluting loop, and monitoring the concentration and the particle size of the aerosol by using an aerosol particle size spectrometer. When the daughter sampling is carried out, sampling can be carried out between the second gas three-way valve and the sampling pump at a rate less than the third air exchange rate, the gas flow discharged by the sampled gas is connected to the air filter, the sampling is a branch bypass of the analog sampling loop, whether the sampling does not affect the third air exchange rate of the sampling pump or not, and the daughter sampling is eliminated²²⁰Rn daughter chamber²²⁰Fluctuation of Rn daughter concentration and unbound fraction, thereby maintaining²²⁰Dynamic equilibrium in the Rn daughter chamber.

²²⁰Under the condition that no aerosol is supplemented in the Rn daughter chamber, the analog sampling loop passes through the third ventilation rate of 5L/min in parallel and the supplementing loop passes through the second ventilation rate of 3L/min in parallelPost-injection of air filter²²⁰Rn daughter chamber, of²²⁰Filtering aerosol in Rn daughter chamber to remove²²⁰Regulating and controlling Rn daughter chamber aerosol at 35 +/-26 cm^-3The experiment shows that the fraction of the non-binding state of ThB can be maintained at (99 +/-0.2)% (stability is 0.2%) for stable operation,²¹²the average Pb concentration is 528Bq/m³(stability 5%),²¹²the fraction of the unbound state of Bi can be maintained at (96.9. + -. 0.53)%, and the ratio of ThC/ThB activity is 0.13. + -. 0.02.²²⁰The Rn daughter chamber is communicated with the aerosol diluting chamber, the aerosol diluting chamber is filled with aerosol with the median diameter of about 100nm through the aerosol generator,²²⁰the concentration of aerosol in the Rn daughter chamber is increased. The aerosol generator replenishes the aerosol in the aerosol diluting chamber at a rate of about 10000/min, the aerosol decaying rate in the diluting chamber is about 700/min, and the aerosol concentration in the aerosol diluting chamber is maintained to be relatively stable through interval replenishment. The aerosol state of different stable concentrations can be adjusted by adjusting the interval time of the input of the aerosol generator²²⁰The stability of Rn daughter chamber aerosol is controlled to be 1246 +/-137 cm^-3When the method is used, the experiment shows that the fraction of the non-binding state of ThB can be maintained to be (27.2 +/-1.4)% (stability is 9.9%) and stably operated,²¹²the average Pb concentration is 1424Bq/m³(stability: 10.4%),²¹²the fraction of the unbound state of Bi can be maintained at (10.7. + -. 2.4)%, and the ratio of ThC/ThB activity is 0.31. + -. 0.03.

The emphasis of each embodiment in the specification is on the difference from the other embodiments, and the same and similar parts among the various embodiments can be referred to each other.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.