Govt. Exams
The dynamic viscosity of water at 20°C is approximately 1.002 × 10⁻³ N·s/m² or 0.001 N·s/m², which is used in Reynolds number calculations.
Bernoulli's equation is valid for inviscid (frictionless), incompressible, steady flow along a streamline. It represents energy conservation in such flows.
Pressure coefficient Cₚ = (P - P∞)/(0.5ρV∞²) is a dimensionless quantity used in aerodynamics and fluid mechanics.
The continuity equation for incompressible flow is based on mass conservation: ρA₁V₁ = ρA₂V₂, which simplifies to A₁V₁ = A₂V₂ when density is constant.
Streamlines represent the paths followed by individual fluid particles in steady flow. They cannot intersect, and velocity is always tangential to streamlines.
Kinematic viscosity is the ratio of dynamic viscosity to density. Its SI unit is m²/s or Stoke (1 Stoke = 10⁻⁴ m²/s).
Second Law states that entropy of an isolated system increases for spontaneous (irreversible) processes and remains constant only for reversible processes
From First Law: ΔU = Q - W = 50 - 30 = 20 kJ (taking work done by system as positive)
Using ideal gas law PV = nRT: T₂/T₁ = (P₂V₂)/(P₁V₁) = (2P₁ × 2V₁)/(P₁V₁) = 4
An adiabatic process has no heat transfer (Q = 0) between the system and surroundings