THERMODYNAMIC PROPERTIES OF WOOD

Question 1

• a branch of physics that studies how energy changes in a system

Answer 1

THERMODYNAMICS

Question 2

• heat is a form of energy that corresponds to mechanical work (that is, exerting a force on an object over a distance)

Answer 2

THERMODYNAMICS

Question 3

• deals with the transfer of energy from one place to another and from one form to another

Answer 3

THERMODYNAMICS

Question 4

• The key concept is that heat is a form of energy corresponding to a definite amount of mechanical work

Answer 4

THERMODYNAMICS

Question 5

• the branch of mechanics concerned with the motion of bodies under the action of forces

Answer 5

DYNAMICS

Question 6

Fire Tetrahedron: Fire can’t exist without the four elements:

Answer 6

1. heat
2. oxygen
3. chemical reaction
4. fuel

Question 7

3 WAYS BY WHICH HEAT CAN BE TRANSFERRED:

Answer 7

1. conduction
2. convection
3. radiation

Question 8

• heat transfer from molecules to molecules

Answer 8

CONDUCTION

Question 9

• heat transfer by the movement of heated particles as in air currents

Answer 9

Convection

Question 10

• energy in the form of heat or light rays is sent out from atoms and molecules as they undertake internal change

Answer 10

Radiation

Question 11

4 ESSENTIAL THERMAL PROPERTIES OF WOOD

Answer 11

1. Thermal Conductivity
2. Heat Capacity
3. Thermal Diffusivity
4. Coefficient of Thermal Expansion

Question 12

• usually represented by k

Answer 12

THERMAL CONDUCTIVITY

Question 13

• measure of the rate at which heat flows through a specified material

Answer 13

THERMAL CONDUCTIVITY

Question 14

• Expressed as the amount of heat that flows per unit time through a unit area subjected to unit temperature difference

Answer 14

THERMAL CONDUCTIVITY

Question 15

• Units used to measure the heat flow or heat transfer are watts per square meter kelvin or W/(m2/k), and sometimes in equivalent units of watts per square meter degree Celsius or W/(m2/°C).

Answer 15

THERMAL CONDUCTIVITY

Question 16

• amount of energy needed to raise the temperature of a specific material (in this case, a wood sample) by 1 degree Celsius (or Kelvin or Fahrenheit).

Answer 16

HEAT CAPACITY OF WOOD

Question 17

factors that affect heat capacity of wood are ________ and ___________ but are basically not affected by its density or species

Answer 17

temperature; moisture content

Question 18

• Measure of how fast a wood can absorb heat from its nearby environment

Answer 18

THERMAL DIFFUSIVITY OF WOOD

Question 19

• It is also defined as the ratio of thermal conductivity to the product of density and heat capacity

Answer 19

THERMAL DIFFUSIVITY OF WOOD

Question 20

• Measures the dimensional changes in wood as affected by changes in temperature.

Answer 20

COEFFICIENT OF THERMAL EXPANSION IN WOOD

Question 21

The oven dry thermal expansion coefficients of a sample wood are positive in _________ (radial, tangential and longitudinal)

Answer 21

all sections

Question 22

wood _______ or _____ on heating and _______ on cooling.

Answer 22

swells or expands; contracts

Question 23

wood has _____heat capacity than steel

Answer 23

high

Question 24

steel has _____ heat transfer than wood

Answer 24

faster

Question 25

wood has ____ thermal diffusivity

Answer 25

lower

Question 26

BTU means

Answer 26

British Thermal Unit

Question 27

• a three dimensional representation of requirements for fire to occur (fuel, heat and oxygen)

Answer 27

Fire Triangle

Question 28

• fuel to release vapor

Answer 28

heat

Question 29

• to sustain combustion

Answer 29

Oxygen

Question 30

• a subsequent exothermic chain reaction in the material

Answer 30

chemical reaction

Question 31

• combustible material

Answer 31

fuel