Aerodynamic testing of ventilation systems is a very important process, without which no building or structure can be commissioned. At the same time, it is necessary to subject such tests to both private housing construction and apartments, as well as industrial production buildings and workshops. Before starting the test, make sure that the construction work is completely completed and the installation of all support systems is completed.
In connection with the appearance on the market of new building materials and equipment, modern devices of ventilation systems are distinguished by a great variety and complexity of designs compared to systems that were used several decades ago. Accordingly, today the requirements for such systems are much higher. And since the correctness and accuracy of ventilation adjustment is one of the most important indicators when commissioning a building, it is necessary to check it with special care, using the most modern and accurate test methods.
Varieties of ventilation systems
In the construction of any buildings or structures, three types of ventilation systems are used. The simplest among them is natural ventilation, when air circulates through the room, penetrating into it and moving away through openings in doors and windows, as well as through ventilation shafts.
If natural ventilation is not enough, then artificial. It is a special supply and exhaust equipment, forcing air to circulate indoors.
Forced ventilation is divided into:
- supply;
- exhaust;
- mixed.
What specific type of ventilation to equip a building, decide in the process of its design, focusing on technical and economic indicators. Moreover, any ventilation must comply with the established sanitary and hygienic standards and rules.
All ventilation systems are characterized by such signs:
- design features;
- appointment;
- air circulation method;
- service zone.
Ventilation requirements
- The purpose of any ventilation system is to create the necessary conditions in the room: temperature, humidity, etc.
- Properly organized ventilation should evenly distribute air.
- A well-ventilated room should be effectively cleaned of dirty air, particles of dust, smoke, foul odors, and quickly enough filled with fresh air from the street.
- The efficiency of indoor air exchange should be monitored by relevant organizations.
- In residential buildings, ventilation should work properly in bathrooms, in kitchens, as well as in nurseries and bedrooms.
- For industrial premises where harmful substances are stored, proper operation of the ventilation system is vital. So, in chemical plants and steel mills, as well as in hospitals, clinics, medical sanatoriums, etc., the air may contain pathogenic bacteria or chemical compounds harmful to health.
Test parameters
Tests of ventilation systems are carried out in order to control the characteristics of air masses so that they comply with established standards and requirements.
During the test, it is checked whether the design calculations were made correctly and whether they correspond to the actual data. The main verification parameters are:
- the amount of air consumed by the system;
- air exchange rate;
- performance indicators of the ventilation system.
Checking the equipment allows you to eliminate the disadvantages, configure the ventilation system to the design capacity at each design point. Control measurements performed during the tests show whether the current indicators correspond to the design coefficient.
If any mounting defect is detected (leaking parts, insufficiently firmly fixed components, poor protection against vibration and noise), all the defects are eliminated. This prevents the occurrence of malfunctions in the system during its operation.
Checking the ventilation system is carried out according to a special document - an explication, in which the plan of all available rooms is fixed and the purpose of each of them is indicated. In addition to the plan, the explication contains a detailed ventilation scheme: all its branches, components and equipment. Each type of equipment must be accompanied by a certificate of conformity or a technical passport.
Independent control
Tests are carried out by employees of special laboratories that are accredited to conduct such inspections. Filling out the passport for the ventilation system is carried out by the organization that performed its installation. Carrying out control measurements and certification should be carried out by independent experts during the acceptance of the system, and not after putting it into operation.
All stages of inspections must be carried out strictly in accordance with the established GOST, determined by the location of the measured sections, which should be located at a distance corresponding to the standards of GOST. This distance is determined by the hydraulic diameter of the air section and the obstructions present in the flow path. Such obstructions can be turns of the duct, grilles and valves.
Starting aerodynamic tests, you must make sure that the throttling devices mounted in the duct are fully open. Also, before testing, it is necessary to open the control devices with which the air distributors of the supply equipment are equipped.
Aerodynamic Testing Equipment
The equipment used for testing, as well as its accuracy class, is selected strictly according to the established GOST.
- The dynamic and total pressure of air masses in a stream, the speed of which is more than 5 m / s, is measured by a combined pressure receiver and a full pressure receiver. The same instruments are used to measure statistical pressure in a steady air stream.
- The relative as well as the absolute humidity of the air, which contains from 10 to 90% of dust and gas particles, temperature and air velocity, dew point is measured with a combined device consisting of an anemometer and a thermohygrometer. Separate use of such devices is allowed.
- The difference and the presence of pressure drops are measured by a pressure gauge.
- Atmospheric pressure is determined using a metrological barometer.
- The temperature of the air flow is determined using a standard thermometer, and humidity using a psychrometer.
- The volumetric air flow rate is determined using a funnel and anemometer.
Test order
- At the initial stage, the heating, conditioning and ventilated equipment is checked for compliance with standards. Passports and certificates for all available devices are also checked.
- At the second stage, the number of measurements to be carried out is determined, the terms of reference are developed, the cost of the test work is determined, and then the cost estimate is made.
- Further, individual tests of ventilation systems are carried out, including documenting the temperature, humidity, pressure, and speed at which the flows move, as well as determining dynamic, statistical and total pressures.In addition, specialists check that the grilles and all valves in the ventilation system are installed correctly. In addition, calculations are carried out to determine at what rate combustion products are removed, etc.
During testing, the formation of explosive concentrations of gases is possible, therefore, checks must be carried out with special care and caution.
Tests should be completed with the execution of all necessary documents - acts, protocols, passports of the ventilation system and individual equipment.
