Greenhouse fan system and pad
The greenhouse fan and pad system are part of the Evaporative Cooling System. Its function is that by suctioning the exhaust fans, water particles enter the air from the cellulose pads installed on the other side of the greenhouse, and these particles absorb the ambient heat to evaporate, thus cooling the air movement path.
The main advantage of the pad and fan system compared to the fogger and the fan is that in the fogger, water with low EC and TDS must be used, but in the pad, about 2 to 3% of the water consumed during the operation of the pad, quality water can be obtained.
This greenhouse cooling system consists of air discharge fans, cellulose pads, storage tanks and water circulations, pumps, water transfer pipes and filters, Water drainage and return equipment and top and bottom frames of cellulose pads (galvanized or aluminum).
The structure and formulation of the pads make it impossible to make it in many countries, despite its many advantages. Today, due to the special production technology of this product, only a limited number of companies are engaged in production of this.
Therefore, selecting and using cellulose pads requires sufficient knowledge and experience. The use of cellulose pads that are only similar in appearance to the original samples not only deprives the greenhouse owner of its benefits, but also imposes a high cost on the employer.
Also, the variety of ventilation fans and their capacities have caused the design of fan and pad system to play a role in temperature control as well as cost management.
Design and calculation of greenhouse fan and pad system in Mazrae Bekr Company
In designing the greenhouse fan and pad system, first of all, it must be ensured that this system is efficient according to the humidity and temperature of the area. Because this system has the lowest efficiency in high humidity conditions and is the most effective cooling method in hot and dry areas. Of course, in the northern regions of Iran, in spring and autumn, the humidity is less than the maximum annual level.
Some of the parameters that are considered in the calculation of the amount of exhaust air, as well as the number of fans, pads, etc., by the designers of the Mazrae Bekr company, are:
1– Light intensity 2- Required pad thickness 3- Height above sea level 4- Calculation of inflow and pressure of incoming water and how to distribute water 5- Calculation of water tanks 6- Difference between beginning and end temperature 7- How to install and place the fan in the greenhouse 8 – Hard distance (pad) from the fan
Of course, designing a principled and practical system of fans and pads at a reasonable price does not end here. Adjusting and reducing the intensity of sunlight by the canopy, in addition to creating suitable growth conditions for the plant, will cause maximum efficiency of the cooling system and prevent the temperature from rising in the distance between the pad and the fan.
In greenhouses where the fan and pad distance are between 30 and 60 meters, it is more efficient. Other lengths may both increase the cost and make it impossible for the system to run properly, in which case the fan-fogger system is a better option.
Another point that should be noted in the pad and fan system is that in greenhouses such as cucumber and tomato greenhouses where the planting rows form a wall, the pad and fan should be installed at the beginning and end of the planting rows, otherwise the planting rows will block the air movement and otherwise the calculations will change.
Also, in two adjacent greenhouses, the greenhouse pad should not be placed in front of the other greenhouse fan. Otherwise, the two greenhouses should be 15 meters apart. In case the fans of two adjacent greenhouses are facing each other, the fans should be installed relative to each other.
Order the complete fan and pad system design: 09158080600
Purchase of fan and pad system equipment: refer to the online store of the greenhouse of Mazrae Bekr Company.