GATE 2025 FLUID MECHANICS 22

Consider the following statement:

1). Hardy cross method is an application of continuity of flow and continuity of potential to direct method of analysis.

2). Hardy cross relationship h_f = k. Qⁿ, where k depends on pipe length, diameter and roughness only.

3). Hardy cross method depends on the idea of head balance method with  around any loop in grid.

Which of these statements are correct?

The ratio of head loss through a pipe in which water is discharged from site at a uniform rate at regular intervals and the end is closed, to the head loss through a pipe carrying uniform discharge.

Ratio of boundary layer thickness to moment thickness for turbulent boundary layer following one seventh power law of velocity profile is

Hardy cross method is used to analyse pipe network in which ⇒ h_f = kQⁿ, where n = 1.8

The modification factor in discharge (ΔQ) will be

Water flow in a 2 cm diameter pipe. The kinematic viscosity()= 0.0098 stokes and  = 1000 kg/m³

Choose the correct option (more than one answer may be correct)

The flow of water (mass density – 1000 kg/m³) and kinematic viscosity = 10^–6 m² /sec, a compressible pipe with equivalent roughness Ks as 0.12 mm yields average shear stress at the pipe boundary = 600N/m². The value of K_s/δ’ (δ’ being the thickness of laminar sublayer) for this pipe is…