Week 8: Literature review - RANS derivation and analysis

AIM Simulate the flow over a cylinder and explain the phenomenon of Karman vortex street   OBJECTIVES Simulate the flow with the steady and unsteady case and calculate the Strouhal Number for Re= 100.  Calculate the coefficient of drag and lift over a cylinder by setting the Reynolds number to 10,100,1000,10000…

AIM To conduct conjugate heat transfer simulation in converge   OBJECTIVES Grid dependence test Start with an initial base grid Run grid dependence test on 3 grids and show that the outlet temperature converges to a particular value Effect of supercycle stage interval Set supercyle stage interval to 0.01,0.02 and…

AIM To run simulations with omega and open-w pistons and characterize the emissions    THEORY Diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression;…

AIM PFI engine simulation using converge   Engine Geometric Parameters Bore =0.086 m Stroke = 0.09 m Connecting rod length = 0.18 m RPM = 3000 Run parameters Simulation mode: No Hydro Simulation time parameters Start time : -520 deg end time : 120 deg Boundary conditions Piston temperature - 450K Liner temperature…

AIM To simulate the flow over a throttle body in converge   OBJECTIVES Set up and run the transient state simulation for flow over throttle body. Post process the results and show pressure and velocity contours. Show the mesh (i.e surface with edges) Show the plots for pressure, velocity, mass flow rate and total…

AIM Surface preparation and Boundary Flagging (PFI)   OBJECTIVE Surface preparation and Boundary Flagging of PFI model Setup a no-hydro simulation   SURFACE PREPARATION Import the PFI engine geometry into converge After running a diagnosis, some errors were found in the geometry   Intersections This error…

AIM RANS derivation and analysis   OBJECTIVE Apply reynold's decomposition to the NS equations and come up with the expression for reynold's stress   THEORY Reynolds-averaged Navier–Stokes equations The Reynolds-averaged Navier–Stokes equations (RANS equations) are time-averaged equations of motion…

AIM To simulate shock tube using converge   OBJECTIVES Setup a transient shock tube simulation Plot the pressure and temperature history in the entire domain  Plot the cell count as a function of time    THEORY Shock tube The shock tube is an instrument used to replicate and direct blast waves at a…

AIM To simulate prandtl meyer shock using converge   OBJECTIVES To study the prandtl meyer shock wave Study the effect of SGS parameter on shock location   THEORY Shock wave In physics, a shock wave, or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium.…

AIM To simulate the flow over a throttle body in converge   OBJECTIVES Set up and run the steady state simulation for flow over throttle body. Post process the results and show pressure and velocity contours. Show the mesh (i.e surface with edges) Show the plots for pressure, velocity, mass flow rate and total cell…

AIM To simulate the flow over a backward facing step in converge   OBJECTIVES Setup the case in CONVERGE Run the case for three different base mesh sizes dx = dy = dz =2e-3m dx = dy = dz =1.5e-3m dx = dy = dz =1.0e-3m   THEORY Flow separation Whenever there is relative movement between a fluid and a solid surface,…

AIM To simulate the channel flow using Converge    OBJECTIVES 1. For this challenge, we will be setting up a channel flow tutorial. 2. Set up the case in CONVERGE 3. Make sure the inlet pressure and initial pressure are the same.  4. Once the base setup is ready, run the case for three different base mesh…

AIM To simulate the combustion of natural gas   OBJECTIVES Part I Perform a combustion simulation on the combustor model and plot the variation of the mass fraction of the different species’ in the simulation using line probes at different locations of the combustor. You need to plot for CO2, H2O, CH4, N2, O2,…

AIM To perform a parametric study on the gate valve   OBJECTIVES To perform a parametric study on the gate valve simulation by setting the opening from 10 % to 80% Obtain the mass flow rates at the outlet for each design point. Calculate the flow coefficient and flow factor for each opening and plot the graph.  …

AIM To perform analysis on cyclone separator and calculate the separation efficiency and pressure drop.    OBJECTIVES To write a few words about any four empirical models used to calculate the cyclone separator efficiency.  To perform an analysis on a given cyclone separator model by varying the particle…

AIM To conduct a CHT analysis on a graphics card   OBJECTIVES Run the simulation by varying the velocity from 1m/sec to 5m/sec for at least 3 velocities and discuss the results. Find out the maximum temperature and heat transfer coefficient attained by the processor. Prove that the simulation has achieved convergence…

AIM  To perform CHT Analysis on Exhaust port   OBJECTIVES Give a brief description of why and where a CHT analysis is used. Maintain the y+ value according to the turbulence model and justify the results.  Calculate the wall/surface heat transfer coefficient on the internal solid surface & show the velocity…

AIM To conduct the Rayleigh Taylor Instability CFD simulation   OBJECTIVES What are some practical CFD models that have been based on the mathematical analysis of Rayleigh Taylor waves? In your own words, explain how these mathematical models have been adapted for CFD calculations. Perform the Rayleigh Taylor instability…

AIM External flow simulation over an Ahmed body   OBJECTIVE To generate velocity and pressure contours.  The drag coefficient plot for a refined case. ( For velocity of 25m/sec, the drag coefficient should be around 0.33). The vector plot clearly showing the wake region.  Perform the grid independency…

AIM Setup steady state fluent simulations in Ansys to compare the mixing effectiveness for short and long pipes.   OBJECTIVES Set up steady-state simulations to compare the mixing effectiveness when hot inlet temperature is 360C & the Cold inlet is at 190C Compare K epsilon and K omega SST model and based on the…

AIM In this challenge you will simulate the same problem as in week 11 but by applying Symmetry Boundary Condition. You will do the simulation for the below mentioned angles using both symmetry and wedge boundary conditions and validate them with HP equations like you did in week 11 challenge.   Angles to test: 10,25,45(degrees)…

AIM Simulate an axi-symmetric flow by applying the wedge boundary condition. The flow is laminar and flows through a constant cross-section pipe at an inlet Reynold's number of 2100. You can do a transient or steady state simulation and you will validate your results with the Hagen- Poiseuille's equations for the fully…

AIM In this challenge, you are going to simulate an incompressible-laminar-viscous flow through the backward facing step geometry. You should perform a transient simulation. The solver can be chosen based on the described physics of the flow. You need to explain the entire simulation procedure (how you set up the case).…

AIM What is Finite Volume Method(FVM), write down the major differences between FDM & FVM. Also, describe the need for interpolation schemes and flux limiters in FVM.    Finite Volume Method The Finite Volume Method (FVM) is a discretization method for the approximation of a single or a system of partial…

AIM In this challenge you are going to simulate the isentropic flow through a quasi 1D subsonic-supersonic nozzle. You will derive both the conservation and non-conservation forms of the governing equations and sovle them using the MacCormack's technique. You need to determine the steady-state temperature distribution…

AIM 1. Steady state analysis & Transient State Analysis Solve the 2D heat conduction equation by using the point iterative techniques. The Boundary conditions for the problem are as follows; Top Boundary = 600 K Bottom Boundary = 900 K Left Boundary = 400 K Right Boundary = 800 K You will implement the following methods…

AIM Derive the following 4th order approximations of the second-order derivative.  1. Central difference 2. Skewed right-sided difference 3. Skewed left-sided difference After deriving these schemes, prove that your skewed schemes are fourth-order accurate i.e the thumb rule   Once you have done this, write a…

AIM Write a function that extracts the 14 co-efficients and calculates the enthalpy, entropy and specific heats for all the species in the data file Calculate the molecular weight of each species and display it in the command window Plot the Cp, Enthalpy and Entropy for the local temperature range (low temperature…

AIM To write a code in MATLAB to optimise the stalagmite function and find the global maxima of the function To understand the concept of genetic algorithm   THEORY Genetic Algorithm (GA) is a search-based optimization technique based on the principles of Genetics and Natural Selection. This algorithm…

AIM Write a program in Matlab\Octave that will simulate the pendulum motion THEORY In Engineering, ODE is used to describe the transient behavior of a system. A simple example is a pendulum The way the pendulum moves depends on the Newtons second law. When this law is written down, we get a second order Ordinary Differential…