Wood Moisture vs. Temperature

9-4 Project 2March 3, 2008

Purpose:

To find out how the size and dryness of wood effects the efficiency of the process of fire.

Hypothesis:

Wood that is dried longer and split will burn hotter in a shorter period of time than wood that is less dry.

Materials

40 sheets of newspaper 10 fir junks, 4” diameter,

16” long, dried 1 year 4 - 2 Lt milk cartons (empty) 40 dried fir splits for kindling Axe Chainsaw Measuring tape Paper Screw driver 16 fir junks, 4” diameter, 20”

long, considered green

Thermal imagining camera 10 fir junks, 4” diameter, 16”

long, dried 3 years Outdoor wood matches Pencil Timer Wood horse Chopping block Chain lubricating oil Bucket Water Fuel – gas/oil

Method

1. Gather materials.

2. Prepare chainsaw by filling with the correct mixture of gasoline and oil, if required. Check the level of chain lubricating oil and fill up, if required.

3. Have an adult use a chain saw, to cut down a fir tree with a 4” diameter and trim off branches. Place log on wood horse. Use measuring tape to measure lengths of 20” and mark by scratching bark of tree with screwdriver. Cut log with chainsaw where indicated. Continue cutting the log until you have 16 pieces of wood. An additional fir tree may be required in order to get the required number of junks. Form a base for each fire by arranging 4 junks of wood lying next to each other, as close a possible. Allow 4’ between each fire. Tear open milk carton and spread flat on junks.

Method(continued)

4. Gather 10 fir junks with 4” diameter, which has been dried 1 year. Divide in two groups of 5 junks. Have an adult use an axe and split one group of junks into splits. Keep separate from other 5 junks.

5. Gather 10 fir junks with 4” diameter, which has been dried 3 years. Divide in two groups of 5 junks. Have an adult use an axe and split one group of junks into splits. Keep separate from other 5 junks.

6. You should have 4 groups:1. Split 1 year old wood2. Solid 1 year old wood in junks3. Split 3 years old wood4. Solid 3 years old wood in junks

Method(continued)

7. Divide your newspaper into 4 groups having 10 sheet in each group. Crumple each sheet of newspaper and place on log base

8. Take your 10 pieces of kindling and lay on top of crumpled paper in a criss-cross pattern.

9. Use a match to light various pieces of paper allow this fire to burn until it reaches at least 720°f. Use thermal imaging camera to measure the temperature. Lay the wood on top of fire and start timer. Allow to burn for 20 minutes. Use thermal imaging camera to measure temperature. Record information on chart.

10. Repeat steps 8 and 9 for the next 3 fires.

11. Analyze findings.

Variables

Manipulated: Age and diameter of wood used.

Responding: The temperature of the fire after burning for 20 minutes.

Controlled:1. The amount of paper.

2. The amount of splits for kindling.

3. The amount of wood.

4. The time that the fire was allowed to burn.

Results

1 yr dried solid

3 yr dried solid

1 yr dried split

3 yr dried split

Fire temperature after burning for 20 minutes

496°f 938°f 598°f 942°f

Results (Continued)

The 3 year old dried wood that was split burned hotter than the wood that was 1 year old and split.

The 3 year old dried wood that was a solid junk burned hotter than 1 year old dried wood that was a solid junk.

There isn’t a significant different between wood that was split compared to wood that was left in a solid junk.

Results(comparing temperature in Fahrenheit)

0

100

200

300

400

500

600

700

800

900

1000

Solid Junk Split Junk

1 year dried

3 years dried

Photos

Conclusion:

Wood that is dried longer burns hotter than wood that isn’t dried. Whether or not the wood was solid or split didn’t have a great effect on the difference in temperature. Therefore, this confirms that my hypothesis was so what correct.

Sources of Error:1. The location, in the fire, that was measured for temperature using the

thermal imaging camera.

2. Direction of wind and the strength of wind outdoors.

3. Placement of wood on the fire.

4. The size and number of splits that the 5 junks produced.

5. Whether or not the wood stacked on the fire had to be repositioned during the burning.

6. Wood for the 5 junks for each of the groups didn’t come from the same tree.

Ways to Improve

1. To have the wood from the same tree that was dried 1 year and 3 years.

2. To have a larger base to place the fire.

3. To measure the temperature that the fire burned at more time intervals.

4. To light the 4 fires at the same time.