How do orchard fans work?

Orchard fans have become the central element in most frost protection strategies. If you have a cordless fan, place it next to your weakest plants and leave it running on the lowest setting possible. The constant flow of air it provides will blow away any lingering water that could lead to ice. This article will help you learn more about the working principles of orchard fans.

The Content list:

1/ the orchard fans for forest protection

2/ how do orchard fans work

the orchard fans for forest protection

Frost fans have become the central element in most frost protection strategies. They use the warmer air in the inversion layer to protect a crop from frost damage. Orchard fans get air from the inversion layer down into and mix with the freezing air at ground level. They have gained popularity lately because they can be used at any time and are energy efficient. Frost fans, on average, cover 10 to 13 acres per fan.

Frost fans are turned on before a frost occurs, usually 0.5 to 1.5°C above freezing. There is documented proof that turning on frost fans early and shutting them down late, results in considerably better crop protection performance. Substantial crop salvage has been achieved with a “slow-freeze-slow-thaw” even under severe frost conditions.

In severe conditions, the use of orchard heaters in conjunction with frost fans strengthens the useable inversion layer which the frost fan then mixes and distributes over the crop, thereby providing better protection.

The initial expense of protecting a large area with frost fans can be significant, but the cost of capital, maintenance, and operation is comparatively lower than other types of frost protection systems.

How do orchard fans work?

In the lower atmosphere, temperature generally decreases with height; But under the condition of early spring pollen, the ground because of radiation cooling and cooling, the closer from the ground, the faster the air cooling, and the upper air is affected by the ground the weak, slow cooling, temperature increases with the rise of the height of the trend, this phenomenon is called "inversion phenomenon" under the condition of the germination of fruit trees fight cold ability is reduced, the buds in 0°C or so will be affected by mild cold injury, 39°C -29°C when severe cold injury ". Orchard fan uses the presence of an inversion layer to artificially alter weather conditions for frost protection. Its working principle is as follows: the orchard fan system is used to physically disturb the air in the near-ground area. On the one hand, warm air above the orchard can be transported to the fruit tree canopy, and the cool and warm air can be fully mixed to raise the temperature of the fruit tree canopy and avoid falling below 0°C.On the other hand, the orchard near the ground air after the disturbance, the formation of micro-airflow, blowing water vapor, can reduce the formation of dew, so as to prevent frost; Even if frost is formed, it will also slow down the rate of frost, and reduce the secondary frost damage of buds and leaves.

Orchard fan mainly uses the "temperature inversion phenomenon" to raise the orchard temperature. The power source of the orchard fan is agricultural electricity or diesel engine. The gearbox and transmission shaft drive the blades to rotate to generate wind energy.

(1) orchard fan can raise the air temperature on the ground and prevent the tree body temperature from falling below 0°C.

(2) orchard fan can stir up the near-ground air of the orchard to form a local airflow, which can disperse water vapor and air and reduce dew formation, thus preventing frost formation.

(3) even if the formation of frost, can also slow down the rate of frost, so as to reduce the secondary freezing damage of fruit buds.

(4) achieve environmental protection, efficient mechanization, automation of large areas of frost prevention.