Question 1 The formula for flow is Q = Velocity X cross sectional area

a) What are the units and dimensions of flow?

b) The Reynolds number is formula which determines the turbulence of flow. What are is the formula? Prove in detail that this is a dimensionless formula by substitution of the units into the formula.

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]