The efficiency of the convection dryer can be found by using the following formula

Efficiency= Radiant energy absorbed / Available radiant energy

where,

Available radiant energy= Amount of radiant energy falling on the surface of a particular region on earth

Radiant energy absorbed= radiant energy absorbed by the black surface of convection dryer.

To calculate the efficiency it was important to collect sufficient and accurate data of the following,

  1. The temperature at the inlet of the air heater,
  2. The temperature at the outlet of the air heater,
  3. the air velocity at the inlet of the air heater,
  4. The air velocity at the outlet of the air heater.

Collection of data:

The temperature and air velocity at the inlet and outlet of the air heater was measured using a windmill anemometer.

Inlet and Outlet air temperature readings using Anemometer

Using the above data the efficiency of the dryer was calculated and was found to be 5 %.