hvac system central air conditioning
DATE:2024-11-25 11:49:58
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Central air-conditioning system fresh air inlet setting requirements 1.Fresh air inlet location
(1) should be located in the cleaner outdoor locations, the inlet of the outdoor air at the harmful substances should not be greater than the maximum allowable concentration of 30% of the indoor workplace. (2) Arrangement should be made so that the exhaust and air inlet as far away as possible. The air inlet should be placed as far as possible on the upwind side of the exhaust outlet (the upwind side of the main wind direction during the season when the air inlet and exhaust are used at the same time), and the air inlet should be lower than the exhaust outlet that discharges the hazardous materials. (3) in order to avoid the inhalation of outdoor ground dust, the bottom of the air inlet from the outdoor floor should not be less than 2 m; arranged in the green zone, should not be less than 1 m. (4) in order to make the summer inhalation of the outdoor air temperature is lower, the air inlet should be located in the back of the building of the shaded area, it is appropriate to be located in the north wall, to avoid being located on the roof and the west wall.
2. Other requirements of the fresh air inlet (1) air inlet should be set up shutters to prevent rainwater from entering, shutters should be fixed shutters, in rainy areas, it is appropriate to use waterproof shutters. (2) In order to prevent birds from entering, it is appropriate to set metal mesh inside the shutters. (3) Transitional season using a large number of fresh air centralized system, it is appropriate to set up two new air inlet, one of which is the smallest new air inlet, the area of the minimum new air volume; the other for the air volume variable new air inlet, the area of the system according to the maximum amount of fresh air minus the minimum amount of fresh air (its wind speed can be achieved a little larger).
Cooling water is a water medium specially used to transfer and reduce the heat generated during the operation of various equipment or systems, so as to ensure that they are maintained within a suitable operating temperature range. In actual life applications, the cooling water system can effectively discharge the waste heat in the air-conditioning system, including the heat of the air-conditioning load and the heat generated by the operation of the chiller, to the outdoor environment.
Therefore, the operating temperature of cooling water is strictly restricted by these two links. (The operating temperature of cooling water includes four characteristic temperatures: inlet and outlet condenser and inlet and outlet cooling tower. If the change of pipeline temperature is not considered, the inlet condenser temperature = outlet cooling tower temperature; outlet condenser temperature = inlet cooling tower temperature)
In the condenser, the refrigerant vapor and cooling water flow through the two sides of the condenser heat exchange tubes for heat exchange. To ensure the smooth transfer of condensation heat in the condenser, the temperature of the cooling water must be lower than the condensation temperature of the refrigerant vapor (the upper limit of the inlet temperature of the condenser). Otherwise, the condensation heat will not be effectively transferred to the cooling water. Based on this principle, my country stipulates that the general inlet water temperature of the cooling water of the condenser is set at 32°C (rated operating conditions).
In the cooling tower system, the cooling water heated by the condenser is in direct contact with the atmosphere, and the waste heat of the air conditioner is discharged through two heat dissipation methods: contact and evaporation. Normally, the inlet water temperature of the cooling tower is consistent with the outlet water temperature of the condenser. In order to ensure that the cooling water effectively dissipates heat in the cooling tower, the temperature when it is discharged from the condenser should be set slightly higher than the outdoor air temperature (the lower limit of the inlet temperature of the cooling tower). my country's regulations recommend setting the outlet water temperature of the condenser cooling water to 37°C (rated operating conditions). The purpose of this setting is to ensure that the inlet water temperature of the cooling tower is higher than the ambient air temperature in most environments, thereby improving the overall heat dissipation efficiency.
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(1) should be located in the cleaner outdoor locations, the inlet of the outdoor air at the harmful substances should not be greater than the maximum allowable concentration of 30% of the indoor workplace. (2) Arrangement should be made so that the exhaust and air inlet as far away as possible. The air inlet should be placed as far as possible on the upwind side of the exhaust outlet (the upwind side of the main wind direction during the season when the air inlet and exhaust are used at the same time), and the air inlet should be lower than the exhaust outlet that discharges the hazardous materials. (3) in order to avoid the inhalation of outdoor ground dust, the bottom of the air inlet from the outdoor floor should not be less than 2 m; arranged in the green zone, should not be less than 1 m. (4) in order to make the summer inhalation of the outdoor air temperature is lower, the air inlet should be located in the back of the building of the shaded area, it is appropriate to be located in the north wall, to avoid being located on the roof and the west wall.
2. Other requirements of the fresh air inlet (1) air inlet should be set up shutters to prevent rainwater from entering, shutters should be fixed shutters, in rainy areas, it is appropriate to use waterproof shutters. (2) In order to prevent birds from entering, it is appropriate to set metal mesh inside the shutters. (3) Transitional season using a large number of fresh air centralized system, it is appropriate to set up two new air inlet, one of which is the smallest new air inlet, the area of the minimum new air volume; the other for the air volume variable new air inlet, the area of the system according to the maximum amount of fresh air minus the minimum amount of fresh air (its wind speed can be achieved a little larger).
Cooling water is a water medium specially used to transfer and reduce the heat generated during the operation of various equipment or systems, so as to ensure that they are maintained within a suitable operating temperature range. In actual life applications, the cooling water system can effectively discharge the waste heat in the air-conditioning system, including the heat of the air-conditioning load and the heat generated by the operation of the chiller, to the outdoor environment.
Therefore, the operating temperature of cooling water is strictly restricted by these two links. (The operating temperature of cooling water includes four characteristic temperatures: inlet and outlet condenser and inlet and outlet cooling tower. If the change of pipeline temperature is not considered, the inlet condenser temperature = outlet cooling tower temperature; outlet condenser temperature = inlet cooling tower temperature)
In the condenser, the refrigerant vapor and cooling water flow through the two sides of the condenser heat exchange tubes for heat exchange. To ensure the smooth transfer of condensation heat in the condenser, the temperature of the cooling water must be lower than the condensation temperature of the refrigerant vapor (the upper limit of the inlet temperature of the condenser). Otherwise, the condensation heat will not be effectively transferred to the cooling water. Based on this principle, my country stipulates that the general inlet water temperature of the cooling water of the condenser is set at 32°C (rated operating conditions).
In the cooling tower system, the cooling water heated by the condenser is in direct contact with the atmosphere, and the waste heat of the air conditioner is discharged through two heat dissipation methods: contact and evaporation. Normally, the inlet water temperature of the cooling tower is consistent with the outlet water temperature of the condenser. In order to ensure that the cooling water effectively dissipates heat in the cooling tower, the temperature when it is discharged from the condenser should be set slightly higher than the outdoor air temperature (the lower limit of the inlet temperature of the cooling tower). my country's regulations recommend setting the outlet water temperature of the condenser cooling water to 37°C (rated operating conditions). The purpose of this setting is to ensure that the inlet water temperature of the cooling tower is higher than the ambient air temperature in most environments, thereby improving the overall heat dissipation efficiency.