applications of computational fluid dynamics in hydraulics

7/29/2019 Applications of Computational Fluid Dynamics in Hydraulics

1/26

APPLICATIONS OF COMPUTATIONAL

FLUID DYNAMICS IN HYDRAULICS

ADITYA KARAN

ABHIJEET SAVANT

TEJAS SHINDE

NINAD PRABHUNE

Guided By :

Prof. G.A. Hinge


2/26

COMPUTATIONAL FLUID DYANAMICS

Computational fluid dynamics/CFD, is a branch of fluid

mechanics that uses numerical methods and algorithms to

solve and analyze problems that involve fluid flows.

Complicated geometry.

Equations in fluids can be complex.

Thus use of computers as a computational tool.

Gambit is used to create the geometries and the

computational grid for the problem. Fluent ,a finite volume solver, is used to solve the discrete

RANS equations.


3/26

Applications of CFD

Used in solving different hydraulic problems .

Used in aerodynamic study .

Used in sports. Used in designing air conditioning systems .


4/26

METHODOLOGY FOR SOLVING A PROBLEM

IN CFD

DEFINE GEOMETRY.

MESHING.

SET BOUNDARY CONDITIONS. SET INITIAL CONDITIONS.

SIMULATION.

POST PROCESSOR.


5/26

In an incompressible fluid the conservation of mass implies

that an equal volume must flow through each location.

HYDRAULICS BASICS


6/26

Work done to move fluid from area1 to area 2


7/26

The mass in each section is given by-

So the net work to raise the fluid from area 1 to

area 2 is

Change in the kinetic energy of the fluid is equal to the work done onthe fluid- conservation of energy

BERNOULLIS THEOREM


8/26

CALIBRATION OF VENTURIMETER


9/26

ABOUT VENTURI METER

The Venturi meter was invented by the Italian GiovanniVenturi in 1797.

To measure the volumetric flow rate of fluids.

GEOMETRY-Venturi meter there is first a convergingsection.

Then there is a short section at the reduced diameter,known as the throat of the meter.

Then there is a diverging section in which the crosssectional area for flow is gradually increased to theoriginal diameter.


10/26

Venturi meter details(FM Lab)

Inlet Diameter= 2.5cm

Throat diameter= 1.6cm

Inlet diameter= outlet diameter Length of inlet pipe=50cm

Length of convergent section=3.5cm

Length of divergent section=6.5cm


11/26

Formulae For Calculating Discharge

C = a1a2(2g) / (a1-a2)

a1 = Area at inlet pipe.

a2 = Area at throat section. C= Coefficient of venturi meter.

Qth= CH

Qth = Theoretical Discharge. H= Difference in venturi head.


12/26

Qact= C.CdH

Qact=Cd Qth

Cd= Coefficient of discharge.

C= 9.75 10-4

* Cd is introduced in the equation because to

take loss of energy into account.


13/26

Comparison between lab and fluent resultsH Lab (cm) H Fluent (cm) Cdlab CdFluent

30 29.1 0.93 0.923

22.1 20.90 0.92 0.9243

9.6 13.63 0.93 0.9250

5.0 5.8 0.92 0.9420

4.0 3.59 0.89 0.8980

1.80 1.96 0.90 0.8790

H = Difference in Venturi Head Cd= Coefficient of discharge of venturimeter


14/26

Geometry and Meshing

Figure showing grid and geometry of venturi meter

Meshing size- 0.01cm resolution


15/26

Different Cases

Case1- discharge=0.412lps (contours of velocity and pressure)


16/26

Case 2- discharge= 0.33lps


17/26

Case 3- discharge= 0.219lps


18/26

Case 4- discharge=0.166lps


19/26

Case 5- discharge=0.12lps


20/26

APPLICATION OF VENTURIMETER

It is used to calculate the velocity and flow

rate of fluids in running through a pipeline.

Used in-

Plumbing- in waste water treatment plant.

Chemical industries- crude oil pipelines.

Carburetors- to control the inflow of air. Medical fields- to measure the flow of blood.


21/26

Inference till date

The Avg. Cd found to be was 0.923 but the

theoretical value of the Cd is usually taken as

0.98.

So, we need to optimise the design of the

venturi meter.


22/26

Objectives

Learning CFD (completed)

Simulation of Venturi meter. ( completed)

Calibration of venturi meter (completed ) Optimisation of venturi meter. (Still working)


23/26

Future Plans

To calibrate different types of flow meters in

CFD .

To simulate and analyse different problems in

hydraulics in CFD .

To explore the innovative world of

computational fluid dynamics in CIVIL

ENGINEERING


24/26

Problems Suffered

Due to absence of actual hardware

requirements the project suffered a set back.


25/26

REFERENCES

"ANSYS FLUENT Flow Modeling Software." Welcome to ANSYS, Inc. -Corporate Homepage. Web. 4 Sept. 2009..

"A Brief History of Computational Fluid Dynamics (CFD) from Fluent." CFDFlow Modeling Software & Solutions from Fluent. Web. 18 Oct. 2009..

"Reynolds Number." Engineering ToolBox. Web. 9 Nov. 2009..

"Reynolds Number." NASA - Title...Web. 03 Dec. 2009.. 26

Computational Fluid Dyanmics By Anderson.


26/26

applications of computational fluid dynamics in hydraulics

Documents