CFD Important Questions
Unit – 1
Q1) Mathematical behavior of PDE’s – (Eliptic,Parabolic and Hyperbolic)
Q2) Mass Conservation equation
Q3) Navier- Stokes Equation
Q4) Reynold’s Decomposition (2 marks)
Q4) Cascade Energy transfer in Turbulent flow (2 marks)
Unit -2
Q1)
Consider the problem of source free heat conduction in an insulated rod whose ends are maintained at
constant temperatures of 200oC and 500oC respectively. The one dimensional problem is governed by
.
Calculate steady state temperature distribution in the rod. Thermal conductivity k=1000 W/m.K, crosssectional area, A is 10X10-3 m2. Length of the rod is 4 m. Use Finite Difference Method.
Q2) Consider the problem of source free heat conduction in an insulated rod whose ends are maintained at
constant temperatures of 400oC and 800oC respectively. The one dimensional problem is governed by
.
Calculate steady state temperature distribution in the rod. Thermal conductivity k=1000 W/m.K, crosssectional area, A is 10X10-3 m2. Length of the rod is 5 m. Use Finite Volume Method.
Q3) Differentiate Explicit Scheme and Implicit Scheme ( 3 marks)
Unit -3
Q 1) A property Φ is transported by means of convection and diffusion through the one –dimensional
domain shown in fig. The governing equation is
The boundary conditions are Φo=1 at x=0 and ΦL=2 at x=L. Using 3 equally spaced cells and the
hybrid differencing scheme for convection and diffusion ,calculate the distribution of Φ as a function
of x for U= 3 m/s. Length, L = 3m , = 1.0 Kg/m3, = 0.1 kg/m.s
Q 2) A property Φ is transported by means of convection and diffusion through the one –dimensional
domain shown in fig. The governing equation is
The boundary conditions are Φo=1 at x=0 and ΦL=0 at x=L. Using 3 equally spaced cells and the upwind
differencing scheme for convection and diffusion ,calculate the distribution of Φ as a function of x for
U= 0.5 m/s. Length, L = 3m , = 1.0 Kg/m3,  = 0.1 kg/m.s
Q 3) A property Φ is transported by means of convection and diffusion through the one –dimensional domain
shown in fig. The governing equation is
The boundary conditions are Φo=1 at x=0 and ΦL=0 at x=L. Using 3 equally spaced cells and the
CENTRAL Difference scheme for convection and diffusion ,calculate the distribution of Φ as a function
of x for U= 0.5 m/s. Length, L = 3m , = 1.0 Kg/m3,  = 0.1 kg/m.s
Q4 ) Write QUICK Scheme Polynomial for Boundary nodes and Internal nodes
Q5) Peclet number (2 marks)
Q6) State the following properties i) conservativeness ii) Boundedness iii) Transportiveness
iv) Accuracy behaviours in central difference, in Upwind scheme in Hybrid scheme
Unit -4
Q1) With Flow chart Derive and explain the steps involved in the SIMPLE algorithm to solve the
incompressible Navier-Stokes equation in two – dimensions indexing using a finite volume grid.
Q2) With Flow chart Derive and explain the steps involved in the SIMPLER algorithm to solve the
incompressible Navier-Stokes equation in two – dimensions indexing using a finite volume grid.
Q3) With Flow chart Derive and explain the steps involved in the PISO algorithm to solve the
incompressible Navier-Stokes equation in two – dimensions indexing using a finite volume grid.
Q4) How SIMPLEC Algorithm differ from SIMPLE algorithm.
Q5) what is staggered grid and why separate grid is required for velocity field calculation( 2 marks)
Unit -5
Q1) Explain Mixing length model.
Q2) Write k-  Turbulence model equations and mention its terms.
Q3)
What is Adaptive mesh refinement (2 marks)
Q4) Turbulence model classification (2 marks)
Q5) Different elements generated Structured Grid
Q6) Different elements generated in unstructured grid