INTRODUCTION
• Low tunnels are temporary, low-profile structures (usually 2 to 4 feet tall) that cover single single crop rows or beds. The frame is simple – often metal rods, flexible PVC, or bamboo pushed directly into the soil. Tunnel film polyethylene (100-150 \mu). UV Stabilized: Prevents the plastic from shattering under sunlight. Infrared (IR) / Thermal: Traps long-wave heat radiation at night, keeping the interior significantly warmer. It Protects crops from adverse weather and Enables off- season cultivation.
OBJECTIVE
To create a controlled environment for plants by maintaining the temperature between 25- 27°C maintaining humidity above 60 to75% monitoring environmental conditions by manual data logging
METHODOLOGY
80% Shade-net is used for the outer covering: This is to restrict the amount of solar energy entering the polyhouse Cooling pads are used for temperature reduction and also for increasing humidity by evaporative cooling. exhaust fan is used to accelerate evaporative cooling Water circulation to keep pads wet
A digital humidity Temperature meter is used for temperature and humidity monitoring
understanding previous project by nachiket that how a polyhouse works
Project planning
Originally the was to build the project with dimensions of 6 ft length, 4 ft height and width of 3 ft
However, after consulting with Arun Dixit Sir, the tunnel dimensions were set to a height of 2.5 feet and a length of 6 feet, featuring a rectangular flat head; a flat head was chosen because a dome-shaped tunnel would have resulted in higher aerodynamic drag.
MATERIAL SELECTION
I have selected the pvc pipe material with elbow and T joint to construct the frame for tunnel, because of that frame will be lightweight and flexible compare to a metal frame
COOLING PAD INFORMATION
Area of the cooling pad will be decided by smaller rectangular in frame which will be opposite to fan section
Length of pad= 3 ft
width of pad =2.5 ft
Total area of pad required= 3×2.5 ft =7.5 square ft
COOLING FAN
Volume Calculation: l×b×h
6×3×2.5=45 cubic ft
Air Changes Per Hour (ACH): Greenhouses require 1 to 2 complete air changes per minute to control heat and humidity
Fan Sizing: volume ÷ minutes per exchange
For 1 air exchange per minute: 45 CFM (ideal for peak summer)
For 1 exchange every 2-3 minutes: 15 to 25 CFM
Temperature can goes very high here in pabal so I will use 50 CFM to 150 CFM fan for the tunnel
STARTED MATERIAL CUTTING FOR TUNNEL
Carefully assembled final frame for the project
