Flow Calculations

Question 1

What is the mass continuity equation in terms of windward and leeward side?

Answer 1

M’w=M’l=M’

Question 2

What is the general process of the calculations?

Answer 2

1. Calculate pressure value and area value for openings on both windward and leeward sides using given equations.

2 .Use mass flow rate equations to get mass flow rate for each side in terms of deltaP.

3. Use mass continuity equation to equate mass flow rates and eliminate unknown term in deltaP. Obtain value for mass flow rate.
4. Use m’ value to get pressures at specified points.
5. May be asked for air exchange rate or cooling power.—Need to remember equations

Question 3

Air exchange rate equation?

Answer 3

V’ = M’/density

V’= Volume exchange rate

ACR= V’ x 3600/V

= air exchange rate per hour

Question 4

Cooling power equation?

Answer 4

Q’= m’Cp(deltaT)