Combustion

Question 1

Partial pressures

Answer 1

P₁/ P Total = n₁/ n Total = V₁ / nₜ

Question 2

AFR

Answer 2

= m air / m fuel

Question 3

Equivalence ratio

Answer 3

= actual AFR / stoichiometric AFR

Question 4

Dewpoint temperature

Answer 4

T dp is T sat @ PV

Question 5

Steady reference state

Answer 5

ΔE sys = ΔE state + ΔE chemical

Question 6

Finding higher heating value for water (liquid from vapour)

Answer 6

HHV = LHV + (N * h fg) H₂O

Question 7

Lamda sensor

Answer 7

Measures oxygen difference between atmosphere and exhaust -> voltage

Question 8

4 ways of measuring AFR in lab

Answer 8

Air vs fuel mass flow rate
Lamda sensor
Horiba calculation
Back calculation from exhaust

Question 9

Flame temperature

Answer 9

Q - W = Σnp (hf° + h - h°) - Σnr (hf° + h - h°)

Question 10

For aA + bB → cC + dD

write Kp using pressures

Answer 10

Kp = PC ^c * PD ^d / PA ^a * PB ^b

Question 11

For aA + bB → cC + dD

write Kp using moles

Answer 11

Kp = ( NC ^c * ND ^d / NA ^a * NB ^b )(P/ NT)^Δv

Δv = c + d - a -b

Question 12

Pollutants from rich combustion

Answer 12

CO CH C

Question 13

NOx production

Answer 13

Very high temperatures - stoichiometric (slight lean)