CN115183352A - PMV-based buried pipe direct supply floor radiation cooling control method and device - Google Patents

Abstract

The invention discloses a PMV-based direct-supply floor radiation cooling control method and device based on a buried pipe. The control method includes the following steps: collecting indoor environments such as floor surface temperature, dry bulb temperature, relative humidity, air flow rate and average radiation temperature. parameters, set the thermal resistance of clothes and the activity intensity of people as fixed values and calculate the PMV value; use the indoor environment dynamic heat and humidity model to predict the PMV value; take the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and take the indoor comfort level as the objective function. The PMV threshold range of the index is a constraint condition, which sets the control rules for the operation of the cooling system; determines the opening time of the ventilation system and the floor radiation system, and adjusts the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the range of the PMV value. To control indoor thermal comfort index PMV. The present invention improves the regulation efficiency and accuracy of the ventilation system and the floor radiation system by adjusting the ratio of the sensible heat load of the ventilation system and the floor radiation system.

Description

Control method and device for direct-supply floor radiant cooling based on PMV

technical field

The invention relates to a control method and device for direct-supplied floor radiant cooling based on a PMV index, belonging to the technical field of air-conditioning optimization control.

Background technique

Buried pipe direct supply floor radiant cooling is currently considered to be a non-ideal cooling method. The floor temperature is controlled above 18-20 °C, which will not produce cold feet in summer and meet thermal comfort requirements. Existing floor radiation and ventilation combined cooling system operation control mainly adopts temperature-based control method, without considering the thermal sensation of people and other indoor environmental parameters. Since the surface of the radiant panel realizes heat transfer through radiation heat exchange and convection heat exchange, compared with the traditional convection method, the thermal comfort of the radiant cooling method will be different, making it difficult to control the indoor temperature set point to meet the thermal comfort. need. And most control technologies adjust the water supply flow and water temperature of the floor radiation system and the air supply volume and air temperature of the ventilation system respectively, without considering the interaction and internal relationship in the cooling process of the two systems, making the composite cooling system energy efficient. and poor control.

The PMV value is an evaluation index proposed by Professor P.O. Fanger of Denmark to characterize the thermal response of the human body (hot and cold sensation), which represents the average of the cold and hot sensations of most people in the same environment. The PMV value can be obtained by estimating the metabolic rate of human activity and the thermal insulation value of clothing, and the following environmental parameters are also required: air temperature, average radiant temperature, relative air velocity and air humidity. Relevant studies have shown that PMV-based control comprehensively considers human activity intensity, clothing thermal resistance, air temperature, average radiant temperature, air flow velocity and air humidity, and can accurately reflect the human body’s direct physiological and psychological responses to the indoor thermal environment. Effective control methods for thermal comfort and reduced energy consumption. In addition, the proportion of cooling load undertaken by the ventilation system in the total cooling load is proved to be a key control parameter of the composite cooling system. Therefore, the reasonable adjustment of the load bearing ratio of the two systems can improve the cooling capacity and energy saving potential of the system.

The indoor thermal comfort index PMV is widely used to evaluate the indoor thermal comfort created by the composite cooling system, which limits the application space of PMV. It is necessary to introduce PMV into the control process to replace the indoor temperature and humidity parameters as a new judgment parameter. Parallel monitoring and control of indoor temperature and humidity to implement accurate and effective system control schemes. However, the research on the load-bearing ratio of the floor radiant system and the ventilation system is limited to describing the change of the load-bearing ratio in the cooling process or proposing a specific load-bearing ratio range to improve the energy efficiency of the system.

SUMMARY OF THE INVENTION

In order to solve the problems of low energy efficiency and poor control effect of the composite cooling system caused by the traditional control method, the present invention proposes a direct-supplied floor radiation cooling control method and device based on the PMV index, which can improve floor radiation and floor radiation. Efficiency and accuracy of regulation of ventilation and composite cooling system.

The technical scheme adopted by the present invention to solve its technical problems is:

On the one hand, a PMV-based direct-supply floor radiant cooling control method provided by an embodiment of the present invention includes the following steps:

Collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature;

The indoor environment dynamic heat and humidity model is used to predict the PMV value;

Taking the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and taking the indoor comfort index PMV threshold range as the constraint condition, set the control rules for the operation of the cooling system;

Determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the interval of the PMV value.

As a possible implementation manner of this embodiment, the PMV threshold range is [-0.5, 0.5].

As a possible implementation manner of this embodiment, the calculation of the PMV value is:

where t _a is the dry bulb temperature, °C; RH is the relative humidity, %; v _a is the air velocity, m/s; t _r is the average radiation temperature, °C; I _cl is the thermal resistance of clothing, clo; M is the activity intensity of personnel, W; W is the mechanical work done by the human body, which is zero when sitting still, J; P _a is the partial pressure of water vapor in the air around the human body, Pa; f _cl is the clothing area coefficient; t _cl is the clothing External surface temperature, °C; h _c is the convective heat transfer coefficient, W/(m ² ∙K).

As a possible implementation manner of this embodiment, the use of the indoor environment dynamic heat and humidity model to predict the PMV value includes:

The dry bulb temperature _ta , relative humidity RH and average radiation temperature t r are predicted by the indoor environment dynamic heat and humidity model, and the PMV value is calculated _by combining the determined air velocity va , clothing thermal resistance I _cl and personnel activity intensity M _;

The indoor environment dynamic heat and humidity model is:

where C _i is the heat capacity of the air node, J/K; T _i is the air node temperature, K; Q _surf,i is the surface radiation and convective heat gain of the envelope, W; Q _env,i is the heat transfer through the wall Heat to the air node, W; Q _inf,i is the heat gain due to infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain (generated by personnel, equipment, lighting, etc.), W; Q _solar,i is the solar radiation heat gain through the window, W; Q _r,i is the cooling capacity provided by the floor radiant system to the air node, W; Q _v,i is the cooling capacity provided by the ventilation system to the air node, W;

In the formula, M _eff,i is the effective moisture capacity of the air node, g/g; ω _i is the moisture content of the air node, g; W _inf,i is the moisture gain caused by infiltrating air, g; W _int,i is the indoor Moisture gain, g; W _env is the moisture transferred to the air node through the wall, g; W _v,i is the moisture removed by the ventilation system, g;

Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve.

As a possible implementation manner of this embodiment, the objective optimization function is:

In the formula, E _pump is the energy consumption of the circulating water pump, kWh; ρ _sw is the water supply density, kg/m ³ ; g is the acceleration of gravity, m/s ² ; H is the head of the circulating water pump, m; V _sw is the water supply volume flow, m ³ /h; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan, kWh; DP is the pressure drop of the fan, Pa; ρ _a is the air supply density, kg/m ³ ; V _sa is the air supply volume flow, m ³ /s; η _fan is the fan efficiency; T _out is the outdoor air temperature, °C; T _set is the set point temperature, °C; T _{out, dew} is the outdoor air dew point temperature, °C; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content, g/kg; ω _max is the maximum moisture content setting value, g/kg.

The constraints are: the pre-cooling process is started through the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start of the staff work; the PMV calculated every 10 minutes is required during the staff work time period. The values all fall within the PMV threshold range.

As a possible implementation of this embodiment, the opening time of the ventilation system and the floor radiation system is determined, and the indoor heat is controlled by adjusting the ratio of the sensible heat load of the ventilation system and the floor radiation system according to the interval of the PMV value. Comfort index PMV, including:

According to the amount of humidity that needs to be removed in the room, as well as the design air supply temperature and design air supply volume of the ventilation system, the pre-dehumidification time required by the ventilation system is calculated, and the opening time of the ventilation system is determined:

In the formula, t is the pre-dehumidification time required by the ventilation system, h; V _sa is the volume flow of the supply air, m ³ /h; W is the indoor moisture to be removed, g; d _in is the indoor air moisture content, g/ kg; d _sa is the moisture content of the supply air, g/kg.

When the floor surface temperature is higher than the dew point temperature, the floor radiant system is turned on;

Before the staff work time, adjust the sensible heat load bearing ratio S _v /S _R of the ventilation system and the floor radiation system according to the range of the PMV value corresponding to the predicted work start time of the staff, and determine the one that meets the PMV threshold requirements and has the lowest energy consumption. Optimum water supply flow, supply air temperature and supply air volume;

During the working time period of the staff, according to the range of the PMV value predicted 10 minutes later at the current moment, adjust S _v /S _R to determine the optimal air supply temperature and air supply volume.

As a possible implementation manner of this embodiment, the working time period of the personnel is from 9:00 to 17:00; the closing time of the floor radiation system and the ventilation system is 17:00.

As a possible implementation manner of this embodiment, the sensible heat load bearing ratio S _v /S _R of the adjustment ventilation system and the floor radiation system is expressed as:

In the formula, Q _{vent .} is the sensible heat load borne by the replacement ventilation system, kW∙h; Q _RFC is the sensible heat load borne by the floor radiant system, kW ∙ h; T _in is the _indoor air temperature, °C; Air temperature, °C; A is the floor surface area, m ² ; h _t is the total heat transfer coefficient, W/(m ² ∙K); T _op is the operating temperature, °C; T _f is the floor surface temperature, °C .

As a possible implementation of this embodiment, the determining the optimal air supply temperature and air supply volume includes:

At the beginning of personnel work, the initial operating parameters of the ventilation system are set: the design air supply temperature and design air volume, and the initial operating parameter settings of the floor radiation system;

If the floor surface temperature does not meet the design requirements, the floor radiant cooling system operates at the maximum allowable water supply flow and remains unchanged;

If the floor surface temperature reaches the design requirements, the floor radiant cooling system operates at the design water flow rate and remains unchanged.

On the other hand, a PMV-based direct-supply floor radiant cooling control device provided by an embodiment of the present invention includes:

The data acquisition and processing module is used to collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature;

The PMV value prediction module is used to predict the PMV value using the indoor environment dynamic heat and humidity model;

The control rule setting module is used to set the control rules for the operation of the cooling system with the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and the indoor comfort index PMV threshold range as the constraint condition;

The cooling system control module is used to determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the range of the PMV value.

As a possible implementation manner of this embodiment, the PMV value prediction module is specifically used to predict the dry bulb temperature _ta , relative humidity RH , and average radiation temperature tr by using the indoor environment dynamic heat and _humidity model , combined with the determined air flow rate v _a , clothing thermal resistance I _cl and personnel activity intensity M , calculate PMV value;

The indoor environment dynamic heat and humidity model includes an indoor environment dynamic heat model and an indoor environment dynamic humidity model;

The dynamic thermal model of the indoor environment is:

where C _i is the heat capacity of the air node, J/K; T _i is the air node temperature, K; Q _surf,i is the surface radiation and convective heat gain of the envelope, W; Q _env,i is the heat transfer through the wall Heat to the air node, W; Q _inf,i is the heat gain due to infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain (generated by personnel, equipment, lighting, etc.), W; Q _solar,i is the solar radiation heat gain through the window, W; Q _r,i is the cooling capacity provided by the floor radiant system to the air node, W; Q _v,i is the cooling capacity provided by the ventilation system to the air node, W;

The indoor environment dynamic wet model is:

In the formula, M _eff,i is the effective moisture capacity of the air node, g/g; ω _i is the moisture content of the air node, g; W _inf,i is the moisture gain caused by infiltrating air, g; W _int,i is the indoor Moisture gain, g; W _env is the moisture transferred to the air node through the wall, g; W _v,i is the moisture removed by the ventilation system, g;

Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve.

As a possible implementation manner of this embodiment, the objective optimization function is:

In the formula, E _pump is the energy consumption of the circulating water pump, kWh; ρ _sw is the water supply density, kg/m ³ ; g is the acceleration of gravity, m/s ² ; H is the head of the circulating water pump, m; V _sw is the water supply volume flow, m ³ /h; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan, kWh; DP is the pressure drop of the fan, Pa; ρ _a is the air supply density, kg/m ³ ; V _sa is the air supply volume flow, m ³ /s; η _fan is the fan efficiency; T _out is the outdoor air temperature, °C; T _set is the set point temperature, °C; T _{out, dew} is the outdoor air dew point temperature, °C; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content, g/kg; ω _max is the maximum moisture content setting value, g/kg.

The constraints are: the pre-cooling process is started through the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start of the staff work; the PMV calculated every 10 minutes is required during the staff work time period. The values all fall within the PMV threshold range.

The beneficial effects that the technical solutions of the embodiments of the present invention can have are as follows:

By adjusting the ratio of the sensible heat load of the ventilation system and the floor radiation system, the invention increases the proportion of the cooling capacity of the ventilation system/floor radiation system, and adds a directional requirement for the adjustment of the cooling capacity of the two systems, thereby improving the composite supply of floor radiation and ventilation. The control efficiency and accuracy of the cooling system solves the problems of low energy efficiency and poor control effect of the composite cooling system caused by the traditional control method.

The present invention takes the lowest energy consumption of the floor radiation and ventilation composite cooling system as the target, and takes the indoor comfort index PMV falling within [-0.5, 0.5] as the constraint condition. In the control method, PMV is used as the judgment parameter, and the sensible heat load bearing ratio Sv/SR of the ventilation system and the floor radiation system is used as the control parameter. PMV does not need to be controlled at [-0.5, 0.5] before the start time of personnel work, so Sv/SR is adjusted according to the range of PMV value corresponding to the predicted start time of personnel work, which can not only meet the PMV threshold requirements, but also save energy consumption; personnel Adjusting Sv/SR according to the predicted PMV value after 10 minutes from the current time during the working time is beneficial to the system to respond to the change of indoor heat gain in time, and effectively solves the problem of the response hysteresis of the floor radiation system. Adjusting the Sv/SR method can clarify the change of the proportion of cooling capacity of the two systems, and can strengthen the synergistic cooling effect of the two systems, so that the cooling capacity can be matched with the demand, and the indoor heat and humidity load can be efficiently handled. On the premise of ensuring indoor comfort, the invention improves the control precision and system energy efficiency of the floor radiation and ventilation composite cooling system.

Description of drawings

1 is a flow chart of a PMV-based direct-supply floor radiant cooling control method based on a PMV shown in an exemplary embodiment;

2 is a structural diagram of a PMV-based direct-supply floor radiant cooling control device based on an underground pipe shown in an exemplary embodiment;

3 is a schematic diagram of a floor radiation and ventilation composite cooling system according to an exemplary embodiment;

FIG. 4 is a flowchart showing a PMV-based direct-supply floor radiant cooling control strategy based on a PMV index, according to an exemplary embodiment.

In Figure 3, 1- Air supply outlet, 2- Cold radiant coil, 3- Air return outlet, 4- Underground heat exchanger, 5- Buried pipe loop circulating water pump, 6- Fan, 7- Surface cooler, 8- Air handling unit, 9 - fresh air inlet.

Detailed ways

Below in conjunction with accompanying drawing and embodiment, the present invention will be further described:

In order to clearly illustrate the technical features of the solution, the present invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in different instances. This repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. It should be noted that the components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and processes are omitted from the present invention to avoid unnecessarily limiting the present invention.

The research on the load bearing ratio of the floor radiation system and the ventilation system is limited to describing the change of the load bearing ratio in the cooling process or proposing a specific load bearing ratio range to improve the energy efficiency of the system, and lack of adjusting the load bearing ratio of the two systems according to the range of PMV In this control method, by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiant system, the proportion of the cooling capacity of the ventilation system/floor radiant system is increased, and the directional requirements for the adjustment of the cooling capacity of the two systems are added to improve the efficiency and accuracy of regulation. sex.

As shown in FIG. 1 , a PMV-based direct-supply floor radiant cooling control method based on a buried pipe provided by an embodiment of the present invention includes the following steps:

Collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature;

The indoor environment dynamic heat and humidity model is used to predict the PMV value;

Taking the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and taking the indoor comfort index PMV threshold range as the constraint condition, set the control rules for the operation of the cooling system;

Determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the interval of the PMV value.

As a possible implementation manner of this embodiment, the PMV threshold range is [-0.5, 0.5].

As a possible implementation manner of this embodiment, the calculation of the PMV value is:

where t _a is the dry bulb temperature, °C; RH is the relative humidity, %; v _a is the air velocity, m/s; t _r is the average radiation temperature, °C; I _cl is the thermal resistance of clothing, clo; M is the activity intensity of personnel, W; W is the mechanical work done by the human body, which is zero when sitting still, J; P _a is the partial pressure of water vapor in the air around the human body, Pa; f _cl is the clothing area coefficient; t _cl is the clothing External surface temperature, °C; h _c is the convective heat transfer coefficient, W/(m ² ∙K).

As a possible implementation manner of this embodiment, the use of the indoor environment dynamic heat and humidity model to predict the PMV value includes:

The dry bulb temperature _ta , relative humidity RH and average radiation temperature t r are predicted by the indoor environment dynamic heat and humidity model, and the PMV value is calculated _by combining the determined air velocity va , clothing thermal resistance I _cl and personnel activity intensity M _;

The indoor environment dynamic heat and humidity model is:

where C _i is the heat capacity of the air node, J/K; T _i is the air node temperature, K; Q _surf,i is the surface radiation and convective heat gain of the envelope, W; Q _env,i is the heat transfer through the wall Heat to the air node, W; Q _inf,i is the heat gain due to infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain (generated by personnel, equipment, lighting, etc.), W; Q _solar,i is the solar radiation heat gain through the window, W; Q _r,i is the cooling capacity provided by the floor radiant system to the air node, W; Q _v,i is the cooling capacity provided by the ventilation system to the air node, W;

In the formula, M _eff,i is the effective moisture capacity of the air node, g/g; ω _i is the moisture content of the air node, g; W _inf,i is the moisture gain caused by infiltrating air, g; W _int,i is the indoor Moisture gain, g; W _env is the moisture transferred to the air node through the wall, g; W _v,i is the moisture removed by the ventilation system, g;

Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve.

As a possible implementation manner of this embodiment, the objective optimization function is:

In the formula, E _pump is the energy consumption of the circulating water pump, kWh; ρ _sw is the water supply density, kg/m ³ ; g is the acceleration of gravity, m/s ² ; H is the head of the circulating water pump, m; V _sw is the water supply volume flow, m ³ /h; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan, kWh; DP is the pressure drop of the fan, Pa; ρ _a is the air supply density, kg/m ³ ; V _sa is the air supply volume flow, m ³ /s; η _fan is the fan efficiency; T _out is the outdoor air temperature, °C; T _set is the set point temperature, °C; T _{out, dew} is the outdoor air dew point temperature, °C; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content, g/kg; ω _max is the maximum moisture content setting value, g/kg;

The constraints are: the pre-cooling process is started through the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start of the staff work; the PMV calculated every 10 minutes is required during the staff work time period. The values all fall within the PMV threshold range.

As a possible implementation of this embodiment, the opening time of the ventilation system and the floor radiation system is determined, and the indoor heat is controlled by adjusting the ratio of the sensible heat load of the ventilation system and the floor radiation system according to the interval of the PMV value. Comfort index PMV, including:

According to the amount of humidity that needs to be removed in the room, as well as the design air supply temperature and design air supply volume of the ventilation system, the pre-dehumidification time required by the ventilation system is calculated, and the opening time of the ventilation system is determined:

In the formula, t is the pre-dehumidification time required by the ventilation system, h; V _sa is the volume flow of the supply air, m ³ /h; W is the indoor moisture to be removed, g; d _in is the indoor air moisture content, g/ kg; d _sa is the moisture content of the supply air, g/kg.

When the floor surface temperature is higher than the dew point temperature, the floor radiant system is turned on;

Before the staff work time, adjust the sensible heat load bearing ratio S _v /S _R of the ventilation system and the floor radiation system according to the range of the PMV value corresponding to the predicted work start time of the staff, and determine the one that meets the PMV threshold requirements and has the lowest energy consumption. Optimum water supply flow, supply air temperature and supply air volume;

During the working time period of the staff, according to the range of the PMV value predicted 10 minutes later at the current moment, adjust S _v /S _R to determine the optimal air supply temperature and air supply volume.

As a possible implementation manner of this embodiment, the working time period of the personnel is from 9:00 to 17:00; the closing time of the floor radiation system and the ventilation system is 17:00.

As a possible implementation manner of this embodiment, the sensible heat load bearing ratio S _v /S _R of the adjustment ventilation system and the floor radiation system is expressed as:

In the formula, Q _{vent .} is the sensible heat load borne by the replacement ventilation system, kW∙h; Q _RFC is the sensible heat load borne by the floor radiant system, kW ∙ h; T _in is the _indoor air temperature, °C; Air temperature, °C; A is the floor surface area, m ² ; h _t is the total heat transfer coefficient, W/(m ² ∙K); T _op is the operating temperature, °C; T _f is the floor surface temperature, °C .

As a possible implementation of this embodiment, the determining the optimal air supply temperature and air supply volume includes:

At the beginning of personnel work, the initial operating parameters of the ventilation system are set: the design air supply temperature and design air volume, and the initial operating parameter settings of the floor radiation system;

If the floor surface temperature does not meet the design requirements, the floor radiant cooling system operates at the maximum allowable water supply flow and remains unchanged;

If the floor surface temperature reaches the design requirements, the floor radiant cooling system operates at the design water flow rate and remains unchanged.

As shown in FIG. 2 , a PMV-based direct-supply floor radiant cooling control device based on a buried pipe provided by an embodiment of the present invention includes:

The data acquisition and processing module is used to collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature;

The PMV value prediction module is used to predict the PMV value using the indoor environment dynamic heat and humidity model;

The control rule setting module is used to set the control rules for the operation of the cooling system with the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and the indoor comfort index PMV threshold range as the constraint condition;

The cooling system control module is used to determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the range of the PMV value.

As a possible implementation manner of this embodiment, the PMV value prediction module is specifically used to predict the dry bulb temperature _ta , relative humidity RH , and average radiation temperature tr by using the indoor environment dynamic heat and _humidity model , combined with the determined air flow rate v _a , clothing thermal resistance I _cl and personnel activity intensity M , calculate PMV value;

The indoor environment dynamic heat and humidity model includes an indoor environment dynamic heat model and an indoor environment dynamic humidity model;

The dynamic thermal model of the indoor environment is:

where C _i is the heat capacity of the air node, J/K; T _i is the air node temperature, K; Q _surf,i is the surface radiation and convective heat gain of the envelope, W; Q _env,i is the heat transfer through the wall Heat to the air node, W; Q _inf,i is the heat gain due to infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain (generated by personnel, equipment, lighting, etc.), W; Q _solar,i is the solar radiation heat gain through the window, W; Q _r,i is the cooling capacity provided by the floor radiant system to the air node, W; Q _v,i is the cooling capacity provided by the ventilation system to the air node, W.

The indoor environment dynamic wet model is:

In the formula, M _eff,i is the effective moisture capacity of the air node, g/g; ω _i is the moisture content of the air node, g; W _inf,i is the moisture gain caused by infiltrating air, g; W _int,i is the indoor Moisture gain, g; W _env is the moisture transferred to the air node through the wall, g; W _v,i is the moisture removed by the ventilation system, g.

Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve.

As a possible implementation manner of this embodiment, the objective optimization function is:

In the formula, E _pump is the energy consumption of the circulating water pump, kWh; ρ _sw is the water supply density, kg/m ³ ; g is the acceleration of gravity, m/s ² ; H is the head of the circulating water pump, m; V _sw is the water supply volume flow, m ³ /h; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan, kWh; DP is the pressure drop of the fan, Pa; ρ _a is the air supply density, kg/m ³ ; V _sa is the air supply volume flow, m ³ /s; η _fan is the fan efficiency; T _out is the outdoor air temperature, °C; T _set is the set point temperature, °C; T _{out, dew} is the outdoor air dew point temperature, °C; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content, g/kg; ω _max is the maximum moisture content setting value, g/kg.

The constraints are: the pre-cooling process is started through the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start of the staff work; the PMV calculated every 10 minutes is required during the staff work time period. The values all fall within the PMV threshold range.

As shown in FIG. 3 and FIG. 4 , combined with specific cases, the following describes the specific process of the present invention based on the PMV index of the direct supply floor radiant cooling control process.

(1) Collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature.

The specific process of step (1) includes:

Indoor environmental parameters are collected regularly, including floor surface temperature, dry bulb temperature _ta , relative humidity RH , air velocity va , and average radiation temperature tr . _Generally , the air velocity va _changes little and is approximately considered to be _a constant value. Set the clothing thermal resistance I _cl and the personnel activity intensity M to be 0.5clo (summer) and 134 W/person respectively, and then automatically calculate the PMV value:

where t _a is the dry bulb temperature, °C; RH is the relative humidity, %; v _a is the air velocity, m/s; t _r is the average radiation temperature, °C; I _cl is the thermal resistance of clothing, clo; M is the activity intensity of personnel, W; W is the mechanical work done by the human body, which is zero when sitting still, J; P _a is the partial pressure of water vapor in the air around the human body, Pa; f _cl is the clothing area coefficient; t _cl is the clothing External surface temperature, °C; h _c is the convective heat transfer coefficient, W/(m ² ∙K).

(2) Use the indoor environment dynamic heat and humidity model to predict the PMV value;

The specific process of step (2) includes:

According to the collected real-time indoor environmental parameters, the dry bulb temperature _ta , relative humidity RH and average radiation temperature t r are _predicted by using the indoor environment dynamic heat and humidity model, combined with the determined air velocity va , clothing thermal _resistance I _cl and personnel activity intensity M , calculate the PMV value;

The indoor environment dynamic heat and humidity model is:

where C _i is the heat capacity of the air node, J/K; T _i is the air node temperature, K; Q _surf,i is the surface radiation and convective heat gain of the envelope, W; Q _env,i is the heat transfer through the wall Heat to the air node, W; Q _inf,i is the heat gain due to infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain (generated by personnel, equipment, lighting, etc.), W; Q _solar,i is the solar radiation heat gain through the window, W; Q _r,i is the cooling capacity provided by the floor radiant system to the air node, W; Q _v,i is the cooling capacity provided by the ventilation system to the air node, W.

In the formula, M _eff,i is the effective moisture capacity of the air node, g/g; ω _i is the moisture content of the air node, g; W _inf,i is the moisture gain caused by infiltrating air, g; W _int,i is the indoor Moisture gain, g; W _env is the moisture transferred to the air node through the wall, g; W _v,i is the moisture removed by the ventilation system, g.

Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve.

(3) Take the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and take the indoor comfort index PMV threshold range [-0.5, 0.5] as the constraint condition.

The specific process of step (3) includes:

(3-1) The objective optimization function is established as:

In the formula, E _pump is the energy consumption of the circulating water pump, kWh; ρ _sw is the water supply density, kg/m ³ ; g is the acceleration of gravity, m/s ² ; H is the head of the circulating water pump, m; V _sw is the water supply volume flow, m ³ /h; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan, kWh; DP is the pressure drop of the fan, Pa; ρ _a is the air supply density, kg/m ³ ; V _sa is the air supply volume flow, m ³ /s; η _fan is the fan efficiency; T _out is the outdoor air temperature, °C; T _set is the set point temperature, °C; T _{out, dew} is the outdoor air dew point temperature, °C; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content, g/kg; ω _max is the maximum moisture content setting value, g/kg.

(3-2) Set the constraints as follows: start the pre-cooling process through the floor radiation and ventilation composite cooling system, and require -0.5 ≤ PMV ≤ 0.5 at the start of the staff work; The PMV value falls in [-0.5, 0.5].

The working hours of the staff are from 9:00 to 17:00. The floor radiant system and ventilation system are closed at 17:00.

(4) Determine the opening time of the ventilation system and the floor radiation system according to the amount of humidity to be removed in the room and the relationship between the floor surface temperature and the dew point temperature, and adjust the sensible heat load of the ventilation system and the floor radiation system according to the range of PMV values. Take the ratio S _v /S _R to control the indoor thermal comfort index PMV.

The specific process of step (4) includes:

(4-1) Calculate the required pre-dehumidification time of the ventilation system according to the amount of humidity to be removed in the room, as well as the design air supply temperature and design air supply volume of the ventilation system, and determine the opening time of the ventilation system:

In the formula, t is the pre-dehumidification time required by the ventilation system, h; V _sa is the volume flow of the supply air, m ³ /h; W is the indoor moisture to be removed, g; d _in is the indoor air moisture content, g/ kg; d _sa is the moisture content of the supply air, g/kg.

(4-2) When the floor surface temperature is higher than the dew point temperature, the floor radiation system is turned on.

(4-3) Before the staff work time, adjust S _v /S _R according to the range of PMV value corresponding to the predicted staff work start time, and determine the optimal water supply flow and air supply that meet the PMV threshold requirements and have the lowest energy consumption. temperature and air volume. After an interval of 10 minutes, collect indoor parameters and predict the indoor parameters corresponding to the start time of personnel work. According to the interval of the calculated PMV value, adjust S _v /S _R to determine the optimal operating parameters. If the start time of personnel work PMV ≤ 0.5, the water supply flow rate of the floor radiation system is adjusted to the design value, and the air supply volume and air supply temperature of the ventilation system are adjusted to the design value; if the personnel work start time PMV > 0.5, increase S _v /S _R , based on the objective function and constraints, the water supply flow of the floor radiation system is adjusted to the maximum value, and the ventilation system adjusts the air supply volume and air supply temperature based on the minimum adjustment range to determine the optimal value.

S _v /S _R can be expressed as:

In the formula, Q _{vent .} is the sensible heat load borne by the replacement ventilation system, kW∙h; Q _RFC is the sensible heat load borne by the floor radiant system, kW ∙ h; T _in is the _indoor air temperature, °C; Air temperature, °C; A is the floor surface area, m ² ; h _t is the total heat transfer coefficient, W/(m ² ∙K); T _op is the operating temperature, °C; T _f is the floor surface temperature, °C .

(4-4) Adjust S _v /S _R according to the range of PMV value predicted 10 minutes later during the working time of personnel, and determine the optimal air supply temperature that meets the PMV threshold requirements and has the lowest energy consumption and air volume. After an interval of 10 minutes, collect indoor parameters and predict the dry bulb temperature _ta , relative humidity RH , average radiation temperature tr after 10 minutes , combined with the determined air flow rate va _, clothing thermal _resistance I _cl and personnel activity intensity M , according to According to the interval of the calculated PMV value, adjust S _v /S _R to determine the optimal operating parameters. If the PMV after 10 minutes is ≤ 0.5, the air supply volume of the ventilation system is adjusted to the minimum fresh air volume, and the supply air temperature is adjusted to the design value; if the PMV after 10 minutes is > 0.5, increase S _v /S _R , based on the objective function and constraints conditions, the ventilation system adjusts the supply air volume and supply air temperature based on the minimum adjustment range to determine the optimal value.

At the beginning of personnel work, the initial operating parameters of the ventilation system are set: the design air supply temperature and the design air supply volume, and the initial operating parameters of the floor radiant system are set: if the floor surface temperature does not meet the design requirements, the floor radiant cooling system will operate at the allowable rate. The maximum water supply flow runs and remains unchanged; if the floor surface temperature meets the design requirements, the floor radiant cooling system operates at the designed water supply flow and remains unchanged.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: the present invention can still be Modifications or equivalent replacements are made to the specific embodiments of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention shall be included within the protection scope of the claims of the present invention.

Claims (10)

1. a direct-supply floor radiant cooling control method based on PMV, is characterized in that, comprises the following steps: Collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature; The indoor environment dynamic heat and humidity model is used to predict the PMV value; Taking the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and taking the indoor comfort index PMV threshold range as the constraint condition, set the control rules for the operation of the cooling system; Determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the interval of the PMV value. 2. the direct supply floor radiant cooling control method based on PMV according to claim 1, is characterized in that, described adopting indoor environment dynamic heat and humidity model to predict PMV value, comprising: The dry bulb temperature _ta , relative humidity RH and average radiation temperature t r are predicted by the indoor environment dynamic heat and humidity model, and the PMV value is calculated _by combining the determined air velocity va , clothing thermal resistance I _cl and personnel activity intensity M _; The indoor environment dynamic heat and humidity model is:

where C _i is the heat capacity of the air node; T _i is the air node temperature; Q _surf,i is the surface radiation and convection heat gain of the envelope; Q _env,i is the heat transferred to the air node through the wall; Q _{inf ,i} is the heat gain caused by infiltrating air; Q _int,i is the indoor convection and radiant heat gain; Q _solar,i is the solar radiation heat gain through the window; Q _r,i is the cooling capacity provided by the floor radiant system to the air node ; Q _v,i is the cooling capacity provided by the ventilation system to the air node;

In the formula, M _eff,i is the effective moisture capacity of the air node; ω _i is the moisture content of the air node; W _inf,i is the moisture gain caused by infiltrating air; W _{int,i is} the indoor moisture gain; The amount of moisture transferred from the wall to the air node; W _v,i is the amount of moisture removed by the ventilation system; Before the start time of personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from outdoor to indoor is less. Therefore, only the amount of waste heat and humidity to be removed is considered, and the above formula is used to solve; The indoor heat source schedule is determined. Since the outdoor weather has less impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve. 3. the direct-supply floor radiant cooling control method based on PMV according to claim 1, is characterized in that, described objective optimization function is:

where E _pump is the energy consumption of the circulating water pump; ρ _sw is the water supply density; g is the acceleration of gravity; H is the head of the circulating water pump; V _sw is the volume flow of the water supply; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan; DP is the fan pressure drop; ρ _a is the supply air density; V _sa is the supply air volume flow; η _fan is the fan efficiency; T _out is the outdoor air temperature; T _set is the set point temperature; T _{out, dew} is the outdoor air dew point temperature ; D h _v is the evaporation enthalpy, J/kg; ω _out is the outdoor air moisture content; ω _max is the maximum moisture content setting value; The constraints are: the pre-cooling process is started through the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start of the staff work; the PMV calculated every 10 minutes is required during the staff work time period. The values all fall within the PMV threshold range. 4. the direct-supply floor radiant cooling control method based on PMV according to claim 1, is characterized in that, described determining the opening time of ventilation system and floor radiant system, and according to the interval of PMV value, by Adjust the proportion of the sensible heat load of the ventilation system and the floor radiation system to control the indoor thermal comfort index PMV, including: According to the amount of humidity that needs to be removed in the room, as well as the design air supply temperature and design air supply volume of the ventilation system, the pre-dehumidification time required by the ventilation system is calculated, and the opening time of the ventilation system is determined:

In the formula, t is the pre-dehumidification time required by the ventilation system; V _sa is the volume flow of supply air; W is the amount of moisture that needs to be removed in the room; d _in is the moisture content of the indoor air; d _sa is the moisture content of the supply air; When the floor surface temperature is higher than the dew point temperature, the floor radiant system is turned on; Before the staff work time, adjust the sensible heat load bearing ratio S _v /S _R of the ventilation system and the floor radiation system according to the range of the PMV value corresponding to the predicted work start time of the staff, and determine the one that meets the PMV threshold requirements and has the lowest energy consumption. Optimum water supply flow, supply air temperature and supply air volume; During the working time period of the staff, according to the range of the PMV value predicted 10 minutes later at the current moment, adjust S _v /S _R to determine the optimal air supply temperature and air supply volume. 5. The PMV-based direct-supply floor radiant cooling control method based on PMV according to claim 1, is characterized in that, described personnel working time period is 9:00～17:00; Described floor radiant system and ventilation System shutdown time is 17:00. 6. The PMV-based direct supply floor radiant cooling control method based on PMV is characterized in that, the sensible heat load bearing ratio S _v /S _R of the adjustment ventilation system and the floor radiant system is expressed as: :

where Q _{vent .} is the sensible heat load borne by the displacement ventilation system; Q _RFC is the sensible heat load borne by the floor radiant system; T _in is the indoor air temperature; T _sa is the supply air temperature; A is the floor surface area; h _t is the total heat transfer coefficient; T _op is the operating temperature; T _f is the floor surface temperature. 7. The PMV-based direct-supply floor radiant cooling control method according to any one of claims 1-6, characterized in that, described determining the optimum air supply temperature and air supply volume, comprising: At the beginning of personnel work, the initial operating parameters of the ventilation system are set: the design air supply temperature and design air volume, and the initial operating parameter settings of the floor radiation system; If the floor surface temperature does not meet the design requirements, the floor radiant cooling system operates at the maximum allowable water supply flow and remains unchanged; If the floor surface temperature reaches the design requirements, the floor radiant cooling system operates at the design water flow rate and remains unchanged. 8. A direct-supply floor radiant cooling control device based on PMV, comprising: The data acquisition and processing module is used to collect indoor environmental parameters, set the thermal resistance of clothes and the activity intensity of personnel as fixed values, and calculate the PMV value; the indoor environmental parameters include floor surface temperature, dry bulb temperature, relative humidity, air velocity and average radiation temperature; The PMV value prediction module is used to predict the PMV value using the indoor environment dynamic heat and humidity model; The control rule setting module is used to set the control rules for the operation of the cooling system with the lowest energy consumption of the floor radiation and ventilation composite cooling system as the objective function, and the indoor comfort index PMV threshold range as the constraint condition; The cooling system control module is used to determine the opening time of the ventilation system and the floor radiation system, and control the indoor thermal comfort index PMV by adjusting the proportion of the sensible heat load of the ventilation system and the floor radiation system according to the range of the PMV value. 9. the direct-supply floor radiant cooling control device based on PMV according to claim 8, is characterized in that, described PMV value prediction module is specifically used for predicting dry bulb temperature t using indoor environment dynamic heat and humidity model _a , relative humidity RH , average radiation temperature tr , combined with the determined air velocity va _, clothing thermal _resistance I _cl and personnel activity intensity M , calculate the PMV value; The indoor environment dynamic heat and humidity model includes an indoor environment dynamic heat model and an indoor environment dynamic humidity model; The dynamic thermal model of the indoor environment is:

where C _i is the heat capacity of the air node; T _i is the air node temperature; Q _surf,i is the surface radiation and convection heat gain of the envelope; Q _env,i is the heat transferred to the air node through the wall; Q _{inf ,i} is the heat gain caused by infiltrating air, W; Q _int,i is the indoor convection and radiant heat gain; Q _solar,i is the solar radiation heat gain through the window; Q _r,i is the air node provided by the floor radiant system Cooling capacity; Q _v,i is the cooling capacity provided by the ventilation system to the air node; The indoor environment dynamic wet model is:

In the formula, M _eff,i is the effective moisture capacity of the air node; ω _i is the moisture content of the air node; W _inf,i is the moisture gain caused by infiltrating air; W _{int,i is} the indoor moisture gain; The amount of moisture transferred from the wall to the air node; W _v,i is the amount of moisture removed by the ventilation system; Before the start time of the personnel work, the gain of indoor heat and humidity is approximately zero, and the heat and humidity transfer from the outdoor to the indoor is less. Therefore, only the amount of waste heat and humidity that needs to be removed is considered and substituted into the above formula to solve; The indoor heat source schedule is determined. Since the outdoor weather has a smaller impact on the indoor thermal environment than the indoor heat source, and within 10 minutes of the collection interval, the outdoor weather parameters change little and are approximately considered constant, so the currently collected outdoor weather parameter values are used. , substituting into the above formula to solve. 10. The PMV-based direct-supply floor radiant cooling control device based on PMV according to claim 8, is characterized in that, described objective optimization function is:

where E _pump is the energy consumption of the circulating water pump; ρ _sw is the water supply density; g is the acceleration of gravity; H is the head of the circulating water pump; V _sw is the volume flow of the water supply; η _pump is the efficiency of the circulating water pump; E _fan is the energy consumption of the fan; DP is the fan pressure drop; ρ _a is the supply air density; V _sa is the supply air volume flow; η _fan is the fan efficiency; T _out is the outdoor air temperature; T _set is the set point temperature; T _{out, dew} is the outdoor air dew point temperature ; D h _v is the evaporation enthalpy; ω _out is the outdoor air moisture content; ω _max is the maximum moisture content set value; The constraint conditions are: the pre-cooling process is started by the floor radiation and ventilation composite cooling system, and the PMV value is required to fall within the PMV threshold range at the start time of the personnel work; the PMV calculated every 10 minutes is required during the personnel work time period. The values all fall within the PMV threshold range.

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