Week 3 - External flow simulation over an Ahmed body.

Aim --> Surface preparation and Boundary Flagging (PFI) Port Fuel Injection System A common type of fuel injection system these days is the Multipoint Fuel Injection System that offers a separate injector nozzle for every cylinder. With port fuel injection, fuel is sprayed into the intake manifold, where…

Aim --> Literature review - RANS derivation and analysis Objective --> To study the Reynolds decomposition on Navier-Stokes Equations and derive the Reynolds-Averaged Navier-Stokes Equation (RANS).  To Understand the term Reynolds stress tensor that appears as a result of Averaging. Compare turbulent viscosity…

Aim --> Shock tube simulation project Theory  The shock tube is an instrument used to replicate and direct blast waves at a sensor or a model in order to simulate actual explosions and their effects, usually on a smaller scale. Shock tubes (and related impulse facilities such as shock tunnels,…

Aim --> Conjugate Heat Transfer Simulation. Conjugate Heat Transfer [CHT] --> The term CHT (Conjugate heat transfer) is a method used to describe processes involving multiple modes of heat transfer [Conduction, Convection, Radiation etc.] between Solids and Fluids due to thermal interaction. This model describes…

Aim --> Prandtl Meyer Shock problem. Introduction The shock wave is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a medium but is characterized by an abrupt, nearly discontinuous,…

Aim --> Transient simulation of flow over a throttle body with Converge CFD. Objectives --> Post-process the results and show pressure and velocity contours. Show the mesh. Show the plots for pressure, velocity, mass flow rate and total cell count. Create animations for throttle movement. Geometry --> Case…

Aim --> Steady-state simulation of flow over a throttle body. Introduction To regulate the power output from an engine there has to be some restriction of how much fuel-air mixture reaches the cylinders. One way to do this is to use some kind of valve that restricts the air, fuel is then regulated to get the correct…

Aim --> Flow over a backwards-facing step Introduction -->  The backwards-facing step is a simple geometry used for visualization of recirculation flow, flow separation and validation of turbulence models. These models are widely used in wing aerodynamics, condensors and vehicles etc. The geometry is shown below.…

Aim -->  Channel flow simulation using CONVERGE CFD. Introduction  Channel flow is an internal flow in which the confining walls change the hydrodynamic structure of the flow from an arbitrary state at the channel inlet to a certain state at the outlet. The simplest illustration of internal flow is a…

Aim --> Sensitivity Analysis of Methane Combustion reactions in GRI 3.0 Mechanism. objective --> Write a code that takes all the reactions from the GRI mechanism and calculates the 10 most sensitive reactions. The sensitivity parameter should be with respect to the Temperature (It should find the sensitivity…

Aim --> Autoignition using Cantera Autoignition is the lowest temperature at which the combustion takes place. It is the time at which the temperature of the mixture is 400 K above the initial temperature of the reactant mixture. The time duration before that is the ignition delay period. Ignition delay is a function…

Multivariate Newton Rhapson Solver Newton Raphson Method is an iterative technique for solving a set of various nonlinear equations with an equal number of unknowns. There are two methods of solutions for the load flow using the Newton Raphson Method. The first method uses rectangular coordinates for the variables while…

When does an ODE become unstable? Stability is a condition in which a slight disturbance in a system does not produce disrupting effect on that system. In terms of the solution of a differential equation, a function f(x) is said to be stable if any other solution of the equation starts out sufficiently close…

Aim --> We need to find the net reaction rate for all four reactions using reactant and product matrices. Then find the production of each species using matrix notation w.r.t net reaction rate. It is compulsory to use the equation editor to type your answers for report submission. Reaction Mechanism Following is the…

Aim --> Combustion Efficiency Calculation after Preheating. --> A furnace is used to burn Methane and Air Mixture. A recuperator is connected to this furnace to recover some energy.  What is the effect of preheating on the adiabatic flame temperature? Change pre-heating from 298 to 600K Explain your results…

Questions 1. Use the "moles" method/function of the A object and explain how it was calculated. You need to use this after line number 9. 2. Use the method mole_fraction_dict() of the A object and explain the result that you get. Here is how you need to use it. print(A.mass_fraction_dict()) 3. What is happening in…

Aim --> To calculate AFT (Adiabatic flame temperature) and its variation using python and Cantera. Objectives --> Adiabatic flame temperature variation with Equivalence ratio (In constant volume-chamber). Adiabatic flame temperature variation with Heat loss (In constant pressure chamber with heat loss). Adiabatic…

Aim --> Simulating Combustion of Natural Gas (CH4 methane-air) using Ansys fluent. Introduction  Combustion or burning is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually, atmospheric oxygen,…

Introduction A Gate valve ( mostly used for large diameters ) is a valve that opens by lifting a barrier (gate) out of the path of the fluid. Gate valves require very little space along the pipe axis and hardly restrict the flow of fluid when the gate is fully opened. Therefore a fully opened valve does…

Aim --> To perform analysis on cyclone separator and calculate the separation efficiency and pressure drop.   Introduction This project is about cyclone seperators. Cyclonic separation is a method of removing particulates from an air, gas or liquid stream, without the use of filters, through…

Aim --> To do CHT (conjugate heat transfer) analysis on a graphics card model. 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…

Aim--> Demonstration of Rayleigh-Taylor Instabilities Rayleigh-Taylor Instabilities Named after Lord Rayleigh and G.I. Taylor It is the instability of an interface between two fluids of different densities which occurs when the lighter fluid is pushing the heavier fluid. Examples are water suspended above the oil in…

Aim --> To Simulate a Conjugate Heat Transfer analysis (CHT Analysis) of the Exhaust Port used in IC Engine. Theory --> Conjugate Heat transfer --> It refers to a heat transfer process involving the interaction of conduction within a solid body and convection from the solid surface…

Aim --> To Analyse External flow simulation over an Ahmed body (basic car model) using Ansys Fluent. Our focus will be to talk about pressure distributions, velocity contours, wake region near the Ahmed body. We also need to use a specific near-wall treatment in the turbulence model and compute the aerodynamic drag/lift…

Aim:-- Simulate the flow over a cylinder and explain the phenomenon of Von-Karman vortex street. Von-Karman Vortex Street --> When a fluid (like air or water) flows externally over a structural body a wake region is formed behind the body. The wake region is the Viscous stress dominated region where the velocity…

Aim:-- To study the steady_state simulation of mixing of two air streams with different temperature and compare their mixing effectiveness. We check the mixing effectiveness for two different lengths(short and long pipe).   Mixing tees are very much used in the HVAC industries. As we can see the above model is…

wedge boundary condition vs symmetry boundary condition --> In this project we have to compare the simulation results obtained for wedge and symmetry boundary conditions, compare and analyse them.Wedge boundary conditions defines a axi-symmetric section of a cylinder and symmetry boundary condition defines a symmetric…

clear all close all clc % code for solving II order PDE (heat conduction) by using point itERATIVE % TECHNIQUE % BC's % top face = 600 K % bottom face = 900 K % left face = 400 K % right face = 800 k % Equation --> [d^2(T)/dx^2] + [d^2(T)/dy^2] = 0 2-D heat conduction % equation w = 1.2; % sucessive over-relaxation…

SIMULATION OF LAMINAR PIPE-FLOW IN OPENFOAM --> In this project we are going to analyse fluid flowing in the pipe and compare computational result (obtained in openFoam) with analytical hagen-poiseuille equation for laminar pipe flow. In the process we are going to capture the laminar Boundary layer development at the…

Block Mesh Challenge In this challange we run a case in openfoam for a step-velocity profile.For that we create a geometry by editing the blockMeshDict file which is a dictianory file. This file contains the information about the geometry, blocks which make up the geometry and the mesh that is generated on the 2D domain.…

clear all close all clc %inputs n=31; x=linspace(0,3,n); dx=x(2)-x(1); gama=1.4; nt=1000;% no. of time steps %calculation of initial profile rho= 1-0.3146*x; T=1-0.2314*x; v=(0.1 + 1.09*x).*T.^0.5; % local sonic velocity a1=(T).^0.5; %area a = 1 + 2.2*(x-1.5).^2; % mass flow rate m=(rho.*v).*a; m_ini=m; % times step %…