INTRODUCTION :

The polycarbonate dome dries the layer faster rate than the metal dome. This data collection is important because from this data we know the drying percent of the each layer for further modification in the dome dryer.

Objective:

  1. To calculate drying percentages and the efficiency of dryer.
  2. To modified efficiency by better air ventilation.

DATE : 21/02/2022

Leftover water and drying percent was extracted with the help of weighing machine by taking a sample of sawdust and water.

Surface area of polycarbonate dome dryer= ᴫr²

Here, diameter = 118cm, radius = 59cm

= 3.14 * 59 * 59

= 10930.64 cm²

= 1.09 m²

Now , calculate the surface area of each layer.

1) Surface area of first layer = 3.14 * (25.75)²

= 0.2 m²

2) Surface area of second layer = 3.14 * (39.25)²

=0.48 m²

3) Surface area of third layer = 3.14 * (47.75)²

=0.71 m²

4) Surface area of fourth layer = 3.14 * (52.25) ²

=0.85 m²

COMPONENTS :

  1. Sawdust
  2. water
  3. Weighing balance
  4. Beaker
  5. Trays
  6. Mould

PROCEDURE :

  1. The mixture of 100 gm sawdust and 100 gm water was firstly measured with the help weighing machine, then weighed all the empty trays.
  2. The mixture is neatly placed in a moulding frame and this moulding frames are taken in tray. Then the frame was gently removed and samples get square shaped.
  3. Then the weight of tray with sample was measured with the help of weighing machine.
  4. After weight of tray is measured it was placed in polycarbonate dome dryer for 6 hours.
  5. After 6 hours again measured the weight of tray and calculate the leftover water and drying percent of the samples.

DATE : 25/02/2022

Samples of sawdust and water were placed in the polycarbonate dome dryer from 11 am to 5 pm. This reading were taken every two hours and average drying percent of each layer was calculated from it.

Fig .Drying the sawdust with different direction

Outcome: But while taking this reading, the shadow was coming on south west side tray for a while, so the reading will be done one more time by changing the position of polycarbonate dome dryer.

DATE : 04/03/2022

After changing the position of polycarbonate dome dryer, I did the same procedure. after taking readings we get average drying percent drying of each layer.

RESULT :

From this data we observed that,

Average drying percentage of first layer is 56.33

Average drying percentage of second layer is 47.58

Average drying percentage of third layer is 42.75.

CONCLUSION :

  1. From this data we understand that south direction has higher drying percent.
  2. The drying percentage of third layer is lower than that of the first and second layer.
  3. We can add ventilation fan to keep the drying percentage in all layers the same.
  4. The base of dome dryer is made of wooden material and if you use aluminium material instead, the heat absorption will be higher.
  5. The substance in the all the trays in the first layer will be shifted to the trays in the last layer and viceversa so that the drying percentage in all the trays will remain the same.

DATE : 9/3/2022

Introduction : In polycarbonate dome dryer I placed trays in only first and second layers for measure the drying percentage. This time trays were placed on all sides of the dryer.

Procedure :

  1. In the first layer, mix 250 gm sawdust and 250 gm water and mix in one tray.
  2. And for the second layer, a mixture of 400 gm of sawdust and 400 gm of water was prepared.
  3. They filled the mixture to the thickness of the tray and then took the weight of the tray.
  4. Then all the trays were placed in the dome dryer for 4 hours for drying.
  5. After 6 hours, the tray was weighed again and calculated drying percentage.

Conclusion :

  1. After 4 hours the average drying percentage is 33 % of the first layer and 23 % of the second layer.
  2. There is a difference of 10 % between the average drying percentage of the first layer and the second layer.

DATE : 12/03/2022

At last time the sawdust fell for the third layer, so the same readings were taken again. But in the third layer 500 gm of sawdust and 500 gm of water were kept so that the thickness of tray would be completely filled.

Fig.Taking reading on polycarbonate dome dryer

OUTCOME:

  1. In south east direction drying percentage is higher than other directions.
  2. There is a difference of 30% between the average drying percentage of first layer at third layer after 6 hours.
  3. There is a difference of 31% between the average drying percentage of first layer at third layer after 4 hours.
  4. There is a difference of 26% between the average drying percentage of first layer at third layer after 2 hours.
  5. Total leftover water is 3913gm from 6900gm water i.e 56.71 % .

Date : 15/03/2022

Introduction:

Efficiency is an important to measure of polycarbonate dome dryer performance. Efficiency is doing right things, while effectiveness is doing the right things. So I calculated the efficiency of dryer. This gives an idea of what percentage of water can evaporate in the substance and what percentage of water is left.

Objectives :

  1. To calculate the efficiency of polycarbonate dome dryer.

Calculation:

We calculate the efficiency of the polycarbonate dome dryer

We know, that total water used in this samples was 6900gm while leftover water is 3913 gm.

Output:

Evaporated water= 6900-3913 = 2987gm

We know, 1gm requires 2230 J energy

Output= 2987*2230 = 6661010 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6661010 / 20282400

= 32.8 %

Result :

Efficiency of polycarbonate dome dryer is 32.8%.

DATE : 17/03/2022

Introduction :

Metal dome dryer has holes for ventilation, so the efficiency of the metal dome dryer was calculated to compare the efficiency of both the metal dome dryer and the polycarbonate dome dryer.

Objectives :

To calculate efficiency of metal dome dryer.

Procedure:

All the trays were filled with a mixture of sawdust and water so that they would fill the trays completely. Each layer had six trays. Different proportions were decided for each layer as follows:

  1. For first layer – 250gm sawdust and 250gm water
  2. For second layer – 400gm sawdust and 400gm water
  3. For third layer – 500gm sawdust and 500gm water

First weighed the empty tray then filled the mixture in it and then weighed it once. This was done every two hours then leftover water was measured. Calculated the drying percentage of each layer.

Fig. Taking reading on metal dome dryer

Calculation:

We calculate the efficiency of the metal dome dryer

We know, that total water used in this samples was 6900gm while leftover water is 3927 gm.

Output: l

Evaporated water= 6900-3927 = 2973gm

We know, 1gm requires 2230 J energy

Output= 2973*2230 = 6629790 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6629790 / 20282400

= 32 %

Outcomes :

  1. South west has the highest drying percentage of metal dome dryer.
  2. Efficiency of metal dome dryer is 32 %.
  3. The metal dome dryer has holes for ventilation, the efficiency of the metal dome dryer is around the polycarbonate dome dryer.
  4. After discussion with Dr. Dixit, it was decided that holes should be drilled on all sides of the dryer to increase the efficiency of the polycarbonate dome dryer.

DATE : 28/03/2022

Discussion:

After discussing with Amey Sir and Dr.Dixit it was understood that there should be as much air flow as there is substance in the dryer. And we decided drilling the holes 1 or 2 cm above the tray level.

DATE : 31/03/2022

Firstly measured its diameter to drill holes 2 cm above the tray level and calculated the area of the each layer.

Fig.Drilling the holes of polycarbonate dome

Calculations :

We know the diameter of each layer,

Formula :

1) Perimeter = πd =3.14*95 = 298 cm

2) Perimeter = πd = 3.14*106 =333 cm

3) Perimeter = πd = 3.14*116 = 364 cm

Now,

calculate the area of each layer.

1) Area of 1st layer = πr² = 3.14*(47.5)² = 7088 cm²

2) Area of 2 ñd layer = πr² = 3.14*(53)² = 8824 cm²

3) Area of 3rd layer = πr² = 3.14*(58)² = 10568 cm²

It was decided to make 5 holes in the first layer, 6 holes in the second layer and 7 holes in the third layer, thus 5 mm holes were drilled in each layer. Firstly draw a complete circle above 2 cm the tray level. Then divide the perimeter by holes and calculate the distance between the two holes. Distance between the two holes of first layer is 59cm, 55cm between the holes of second layer and 52 cm between the holes of third layer. Thus holes were drilled in each layer from this data

DATE : 5/4/2022

Introduction :

This time I took same trail as the first one, only this time I had drilled holes in the dryer and another trail was taken. The efficiency of the dome dryer was calculated from the readings taken.

Objective :

To increase the efficiency of polycarbonate dome dryer.

Fig.Compressed the sawdust with help of small tray

Calculation :

We know total water used 1500 gm in first layer, 2400 gm in second layer and 3000 gm in third layer. Out of this only 4000 gm of water remained and 2900 gm of water evaporated.

We know, 1gm requires 2230 J energy

Output= 2900*2230 = 6467000 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939=20282400 J

Efficiency = output / input

= 6467000 / 20282400

= 31.88 %

Outcome :

When I calculated the efficiency, it was completely the opposite, the efficiency was decreasing by one percent instead of increasing.

DATE : 12/04/2022

Objectives : I took the same reading again to find out if this reading is correct. For that, I did the same process and took reading.

We calculate the efficiency of the polycarbonate dome dryer

We know, that total water used in this samples was 6900gm while leftover water is 4224 gm.

Output:

Evaporated water= 6900-4224 = 2676gm

We know, 1gm requires 2230 J energy

Output= 2676*2230 = 5967480 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6967480 / 20282400

= 29.42 %

Conclusion :

This is a calculation correct. Efficiency decreases in both readings. This shows that if the holes are drilled, the efficiency is further reduced.

DATE : 14/04/2022

I calculated how much water evaporated from each layer of both the polycarbonate dome dryer with holes and the polycarbonate dome dryer without holes.

Table. Amount of water evaporate in gm

DATE : 15/04/2022

We decided to take the same readings three more times to find out why the dome had less efficiency after the holes were drilled.

We know, leftover water is 4127 gm.

Output:

Evaporated water= 6900-4127 = 2773gm

We know, 1gm requires 2230 J energy

Output= 2773*2230 = 6183790 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6183790 / 20282400

= 30.48 %

Outcome :

It was noticed that if the holes were closed and readings were taken, the efficiency was increase.

DATE : 19/04/2022

Introduction :

The data collection reading of the polycarbonate dome dryer is repeated twice as it will determine whether the efficiency really decreases when the holes are drilled. Decided to read four times like this by closing the holes twice and keeping the holes open twice. The holes closed and took readings.

Fig.Put the tray in the dryer to dry for 6 hours

We calculate the efficiency of the polycarbonate dome dryer

We know, that total water used in this samples was 6900gm while leftover water is 4219 gm.

Output:

Evaporated water= 6900 – 4219 = 2581 gm

We know, 1gm requires 2230 J energy

Output= 2581*2230 = 5755630 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6967480 / 20282400

= 28.37 %

DATE : 22/04/2022

Close the holes and repeat the same readings.

Fig. Taking reading with closes holes of polycarbonate dome dryer

From this we calculate the efficiency of polycarbonate dome dryer.

We calculate the efficiency of the polycarbonate dome dryer

We know, that total water used in this samples was 6900gm while leftover water is 4207 gm.

Output:

Evaporated water= 6900-4207 = 2693gm

We know, 1gm requires 2230 J energy

Output= 2693*2230 = 6005390 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6005390 / 20282400

= 29.60 %

DATE : 26/04/2022

Leave the holes open and repeat the same reading.

Fig.Taking reading with open holes of polycarbonate dome dryer

We know, leftover water is 4154 gm.

Output:

Evaporated water= 6900-4154 = 2746gm

We know, 1gm requires 2230 J energy

Output= 2746*2230 = 6123580 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6123580 / 20282400

= 30.19 %

DATE: 28/04/20222

Leave the holes open and repeat the same reading.

Fig. Drying the sawdust with open holes of dryer

We know, leftover water is 3596 gm.

Output:

Evaporated water= 6900-3596 = 3304gm

We know, 1gm requires 2230 J energy

Output= 3304*2230 = 7367920 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 7367920 / 20282400

= 36.32 %

DATE: 03/05/2022

Today, two out of five diagonally opposite holes in the top layer of polycarbonate dome dryer were closed with cellotape and readings were taken. I did same process today as I did last time.

We know, leftover water is 4203 gm.

Output:

Evaporated water= 6900-4203 = 2697gm

We know, 1gm requires 2230 J energy

Output= 2697*2230 = 6014310 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939 =20282400 J

Efficiency = output / input

= 6014310 / 20282400

= 29.85 %

Result:

  1. The drying percentages of dryer was 43.28%.
  2. Efficiency of polycarbonate dome dryer was 32.84%.
  3. After drilling the holes that is improve the air ventilation efficiency was increased by 3-4 % and it was 36.32%.

CONCLUSION:

I wanted to find out efficiency of dryer for uniformity of drying material. I have used sawdust as a medium and measured quantity of water is added to it. I have calculated efficiency of dryer in a drying tray located at south, south east, south west, north, north east and north west directions. I have also calculated drying efficiency on different levels of tray in a dryer. I have observed that efficiency will increase if ventilation is improved. Hence I have drilled holes at different levels. Without holes for ventilation efficiency was 32%. After making holes efficiency has increased to 36%. Therefore I have recommended Vigyan Ashram to make ventilation holes to polycarbonate dome dryer.

FABRICATION OF SOLAR FLAT DRYER

DATE: 05/05/2022

  • Cut flat bars for fabrication of solar flat dryer then welded the flat bar.
  • Drilled holes in the angle bar to create the frame.
Fig. Parts of frame
Fig. Assemble the frame
  • I fixed the nut and bolt to that frame and saw that there are no problems in it.
  • Then I painted the plywood of solar flat dryer by black color.
  • When the plywood dries, checked if its fits snuggly in the frame. Corner of the plywood was cut because the nut and bolt in the corner did not fit properly.
  • I stapled the base plywood of dryer with tarpaulin.
  • Then drilled the holes to fit the side of plywood as well as polycarbonate sheet and fixed it with a nut, bolt and washer.
  • Then holes were drilled to attach the lock to polycarbonate sheet.
  • After this the side and base of plywood were fixed in the frame and top was covered with polycarbonate sheet.
  • This is how the solar flat dryer was made.
Fig. Paint the plywood

DATE: 07/05/2022

OBJECTIVE:

Calculate drying percentage of solar flat dryer.

INTRODUCTION:

I took a trail in solar flat dryer. The sample was prepared by mixing 100 gm of sawdust and 100 gm of water and kept in the dryer for 6 hours. The weight of tray was taken after 6 hours

Fig. Dried sample in flat dryer

CALCULATION:

Drying percentage of solar flat dryer = Water evaporated/Total water*100

= 179/200*100

=89.5%.

Output:

Evaporated water= 179gm

We know, 1gm requires 2230 J energy

Output= 179*2230 = 399170 J

We know, solar irradiance for 6 hr = 939 J/s for 1m2

Input = 6*60*60*939*0.045 = 912708 J

Efficiency = output / input

= 399170 / 912708

= 43.73 %

DATE : 10/05/2022

I took enough sawdust to cover the entire area of solar flat dryer. Spread the mixed sawdust to dry in the solar flat dryer for 6 hours. After 6 hours the weight of that sawdust was 6560 gm of this 4860 gm was sawdust

Fig. Drying the sawdust in solar flat dryer

Total water remained = 6560- 4860 = 1700 gm

Out of 4860 gm only 1700 gm water remained.

Hence, Water evaporated = 4860-1700= 3160 gm

From this, % Water loss= 3160/4860*100 = 65 %.

Output:

Evaporated water= 3160gm

We know, 1gm requires 2230 J energy

Output= 3160*2230 = 7046800 J

total area of polycarbonate sheet = 1.56 m2

We know, solar irradiance for 6 hr =1.56* 939 = 1464.8 J/s

Input = 6*60*60*1464.8 = 31640544 J

Efficiency = output / input

= 7046800 / 31640544

= 22.27 %

OUTCOMES:

It had been cloudy climate since noon and the sawdust remained moist due to insufficient heat. This reduces the efficiency of the dryer.

FABRICATION OF METAL DOME DRYER

DATE : 11/05/2022

  • The inside of metal dome dyer is covered with a sheet of aluminum to close the gap between the two parts.
  • Then took the dimensions and cut the sheet.
  • After cutting the sheet, the sheet was neatly placed at a gap and the holes was drilled then fixed sheet by rivets.
  • We filled a gap in the top of the metal dome dryer with metal putty and m seal.
  • Then we polished the metal dome dryer is polished with polish paper.
  • The stand of metal dome dryer is polished with an angle grinder. After polishing, the stand was given a red oxide color.
Fig. Polish the stand of metal dome dryer
  • Painted the base plywood of metal dome dryer with black color.
  • Then painted the stand and cap of metal dome dryer.
Fig. Painted base and stand of metal dome dryer