What is Ventilation Negative Pressure and What is Positive Pressure Ventilation? What is Negative Pr

The prerequisite for negative pressure ventilation is in a relatively sealed space. Negative pressure fan on one side of the wall.

Forcibly pumping out the indoor air will form an instantaneous relative vacuum (negative pressure), and the water curtain installed on the other wall has many small holes, and the outdoor air is at atmospheric pressure.

Don't underestimate the atmospheric pressure, in fact, the pressure is very high, and we don't feel it because we are used to this pressure). As a result, the air is constantly circulating with the outside. If installed properly, all the air in the room will participate in this large circulation.

Therefore, for rooms with dirt, smoke, dust, and odors, this ventilation mode is the most thorough. Considering the input cost, some customers will only choose a negative pressure fan instead of installing a cooling curtain. At this time, the air opposite the fan enters through the doors and windows, and there is no cooling treatment.

Indoor air flow will also have a better cooling effect.

Negative pressure fan.

The fan (usually the negative pressure fan) installed on one wall of the space draws out the indoor air, resulting in the indoor air pressure instantaneously less than the atmospheric pressure or less than the normal pressure, at this time, the other side of the space (often the opposite side of the negative pressure fan installed) has an air inlet, and the outside air automatically enters the space under the atmospheric pressure. As a result, a directed, stable airflow zone is formed in space. This type of ventilation is often referred to as negative pressure ventilation.

It is characterized by a directional, stable airflow that is connected to the outside world rather than an internal circulation in space. It is usually achieved by using a negative pressure fan instead of a traditional axial fan, etc. If there is a cooling water curtain installed on the opposite side of the negative pressure fan, then the outside air will exchange heat with the water and the temperature will drop when passing through the wet water curtain at this time, and the cooling effect on the space will be very significant.

Fan pad ventilation case.

What is Positive Pressure Ventilation? What is Negative Pressure Ventilation?

Hello Kuchang, dear! It's a pleasure to serve you. Positive pressure ventilation refers to the ventilation method in which fresh air outside the house is forcibly sent into the house through the fan, so that the air pressure in the house increases, and the dirty air in the house is naturally discharged through the tuyere or air duct.

Negative pressure ventilation refers to the air in the house sliding out through the fan grip, causing the air pressure in the house to be less than that outside the house, and the air outside the house flows into the house through the air inlet or air intake pipe.

Fresh air system, as a new type of ventilation and purification equipment, is gradually integrated into the public family. Recently, some customers have asked which type of household fresh air system is suitable, negative pressure filter ventilation or positive pressure filter ventilation, which is better?

Negative pressure fresh air system refers to the uninterrupted and continuous discharge of indoor dirty air to the outside by the ultra-quiet fan, so that the indoor air forms a negative pressure. Also known as one-way flow fresh air system, it is forced exhaust and natural air supply. Its working principle is that the fresh fan will exhaust the indoor polluted air, and the outdoor fresh air will enter the room from the door, window and other places to achieve the effect of ventilation.

At this point, the indoor air is under negative pressure.

The positive pressure fresh air system is also a two-way flow fresh air system, which is forced air supply and forced exhaust. Its working principle, through the micro-positive pressure operation, can effectively clean the outdoor fresh air and send it to the room after filtration, and discharge the indoor polluted air. So that the dirty air can not enter the room, only after purification and filtration, the air can only enter the room through the air duct, so that the room is always full of fresh air.

The intelligent exhaust of the negative pressure fresh air system can not purify the outdoor air, and cannot meet our desire to replenish fresh air indoors, especially for the current environment with serious air pollution, especially during the haze period, it is really not applicable. The positive pressure fresh air system can filter and purify the outdoor air, meet our demand for high-quality air, and replace the indoor dirty air more thoroughly. Moreover, on the basis of the positive pressure fresh air system, the Mia fresh air system is also equipped with a full heat exchanger, which not only realizes the replacement of indoor and outdoor air, but also ensures that the indoor temperature and humidity are suitable, reduces the consumption of indoor air conditioning and heating energy, and truly achieves comfort and health while saving energy and environmental protection.

Positive pressure ventilation and negative pressure ventilation, I think this must still be positive pressure, and the ventilation will be better, because the efficiency of air circulation will be faster, so the ventilation effect will be faster.

Which effect is better with positive pressure ventilation with small pass? The main thing is that you choose the equipment to see which equipment you are configuring in the selection.

The negative pressure is based on the operating data of the main ventilators. The static pressure and negative pressure of the fan are equal in size, and the fan is a machine that relies on the input mechanical energy to increase the gas pressure and send the gas in a row, and it is a driven fluid machine. The exhaust pressure is lower than that of Pa.

Modern ventilators are widely used for ventilation, dust removal and cooling in factories, mines, tunnels, cooling towers, vehicles, ships and buildings, ventilation and induced air in boilers and industrial furnaces, cooling and ventilation in air conditioning equipment and household appliances, drying and selection of grain, inflation and propulsion of wind tunnel air sources and hovercraft, etc.

Ventilators are widely used for ventilation, dust removal and cooling in factories, mines, tunnels, cooling towers, vehicles, ships and buildings; ventilation and induced air for boilers and industrial furnaces; cooling and ventilation in air-conditioning equipment and household appliances; drying and selection of grains; Wind tunnel wind source and hovercraft inflation and propulsion, etc. The following are the product parameters of a low-noise post ventilator.

The negative pressure is based on the operating data of the main ventilators.

However, the ventilation resistance can be reflected by the negative pressure of the mine, and the relationship between the two is as follows:

The greater the ventilation resistance of the mine, the greater the negative pressure of the mine, and the greater the negative pressure of the mine, which proves that the air volume of the mine is large.

Static pressure: refers to the difference between the absolute static pressure of a measurement point in the shaft and the atmospheric pressure of the elevation outside the shaft. The relative static pressure at any point on either side of the mine is negative, so the extractable fan is often called negative pressure ventilation.

A good indoor ventilation environment is conducive to our health, reducing indoor odor, removing indoor decoration pollution, reducing the breeding of germs in the air, etc., in short, indoor ventilation has many benefits, indoor ventilation is eliminated, this is what it means. However, some environments have limited natural ventilation, which requires us to transform the passive ventilation environment, no matter what kind of auxiliary materials are used, which are nothing more than positive pressure air supply or negative pressure air supply. So how should we choose?

First of all, understand the principle of the two air supply methods, use the fan equipment to send the outdoor air indoors, the indoor air pressure will increase slightly, because of the pressure difference between the indoor and the outside, the air will overflow through the gaps in the doors and windows to achieve air circulation, which is called micro positive pressure air supply. On the contrary, the indoor air is pumped out by mechanical equipment and sent to the outdoors, so that the indoor pressure will be less than the outdoor pressure, and the air will flow into the room through the gaps in the indoor doors and windows to achieve air circulation, which is called negative pressure air supply.

In the usual environment, the place with good enclosure, or the place where the air supply is far away, in order to have a better ventilation effect, most of the general choice is micro positive pressure air supply, so that the air circulation will be better, so the current commercial ventilation system, household fresh air system, whether it is one-way flow or two-way flow, generally choose micro positive pressure air supply system.

So what kind of place is the use of micro negative pressure air supply? Generally, in the air with peculiar smell, in a semi-open environment, a slight negative pressure air supply method is generally used, such as the kitchen, bathroom, factory workshop and so on in our family. If these places choose to use positive pressure air supply, the smell of oil smoke or bathroom odor is everywhere in the home place, which will aggravate the air pollution of the entire home environment; If the factory building chooses positive pressure air supply, it will lead to colder winters and hotter summers, which will directly affect the operation of workers and equipment.

All in all, negative pressure air supply can be used in any environment to achieve passive ventilation, but the ventilation effect is good or bad, so in ventilation construction, especially in the home environment, micro positive pressure air supply is the preferred air supply scheme.

Positive pressure is along the ventilation, and negative pressure is against the ventilation. It doesn't matter, you can choose directly to the owner's preference. Positive pressure is just more power-saving.

In fact, to put it bluntly, it is the role of positive pressure air supply and negative pressure air extraction, which is also to better form the equipment of circulating air, which can make the wind circulate better and protect people from escape in the event of a fire.

The negative pressure is based on the operating data of the main ventilators. However, the ventilation resistance can be reflected by the negative pressure of the mine, and the relationship between the two respecters is as follows: the greater the ventilation resistance of the mine, the greater the negative pressure of the mine, and the greater the negative pressure of the mine, which proves that the air volume of the mine is large.

Static pressure: refers to the difference between the absolute static pressure of a measurement point in the shaft and the atmospheric pressure at the elevation outside the shaft. The relative static pressure of any point on either side of the mine is negative, so the hidden field extraction fan is often called negative pressure ventilation.

Positive pressure ventilation and negative pressure ventilation are two different ways of air flow, which are mainly used to control indoor air quality and environmental conditions. They differ in the direction of the air flow and how it is transmitted:

1.Positive pressure ventilation: Positive pressure ventilation is to provide air pressure higher than the outdoor air pressure indoors, so that the indoor air flows to the outside of the car, so as to discharge indoor pollutants and moisture.

Positive pressure ventilation usually provides air through a fan or air conditioning system to maintain positive pressure in the room. This ventilation method is suitable for preventing external contaminants from entering internal spaces, such as hospital operating rooms, clean rooms, etc.

2.Negative pressure ventilation: Negative pressure ventilation is to maintain the air pressure lower than the outdoor air pressure indoors, so that the outdoor air enters the room, and the harmful substances in the room are discharged.

Negative pressure ventilation expels indoor air through the exhaust system or exhaust duct, thus forming a negative pressure environment. This type of ventilation is suitable for preventing the spread of harmful substances to other areas, such as isolation rooms, laboratories, etc.

In summary, positive pressure ventilation expels indoor air by providing airflow to the outside; Negative pressure ventilation expels indoor air by bringing in airflow from the outside. Choosing which ventilation to use requires evaluation and decision based on the specific site needs and environmental conditions. <>

Ventilation principle: the negative pressure fan discharges air to the outside to reduce the indoor air pressure, and the indoor air becomes thinner, forming a negative pressure area, and the air flows into the room due to the compensation of the air pressure difference.

In the practical application of industrial plants, the negative pressure fan is installed on one side of the plant, the air inlet is on the other side of the plant, and the air is convection from the air inlet to the negative pressure fan.

In this process, the doors and windows near the negative pressure fan are kept closed, and the forced air is compensated for by the doors and windows on the side of the air inlet into the workshop. The air flows into the workshop in an orderly manner from the air intake, flows through the workshop, and is discharged from the workshop by the negative pressure fan.

The ventilation is thorough and efficient, and the ventilation rate can be as high as 99%. Through specific engineering design, according to the need to design the ventilation speed and wind speed, any high heat, harmful gases, dust and smoke can be quickly discharged from the workshop, and any poor ventilation problems can be completely solved at one time. Ventilation can be achieved within seconds of turning on the fan.