1. Ali Ahmadi
Personal Information:
Date of Birth: May 25th
, 1987
Marital Status: married
Tel: +989376418248, +981736222378
Email: ali_ahmadi@alum.sharif.edu , darya.ghoroob@gmail.com
Education:
A) 2014:
Ph.D. Candidate in Marine Engineering, Sharif University of Technology (SUT),
Tehran, Iran.
Thesis: not defined
Supervisor: Prof. Madjid Abbaspour Tehranifard
Co-Supervisor: Dr. Mohammadreza Tabeshpour
B) 2010-2012:
M.Sc. in Marine Engineering, Sharif University of Technology (SUT), Tehran, Iran.
Thesis: Numerical Modeling of Regular Wave and Conventional Tension Leg Platform
Interaction using Boundary Element Method and Modified Euler Method
Supervisor: Prof. Madjid Abbaspour Tehranifard
GPA: 16.63
C) 2006- 2010:
B.Sc. in Ship Building Engineering, Malek-e-Ashtar University of technology
(MUT), ShahinShahr, Isfahan, Iran.
Thesis: Design of Offshore Wind Turbine Support Structure Appropriated for Persian
Gulf using DNV standard
GPA: 15.39
Honors:
1st
rank in Iran PhD entrance exam in Marine Engineering group in 2014.
Top MSc thesis in 2012 selected by Iranian Association of Naval Architecture
and Marine Engineering, praised in 14th
marine industries conference.
9th
rank in Iran MSc entrance exam in Marine Engineering group in 2010.
2. Research Experiences (except thesis and work experience):
Hydrostatic and Hydrodynamic Design of a cargo ship by Maxsurf
Propeller design for an AUV
Design a conventional TLP by MOSES
Developing a computer code to calculate added mass, damping and wave force on
two dimensional mono-hull and catamaran section using BEM in MATLAB
Developing a computer code to calculate wave force on array of bridge piles for
several different section geometries using BEM in MATLAB
Developing a computer code to calculate Morison wave force and moment on
bridge pile in desired section in MATLAB
Developing a computer code to evaluate hydrostatic situation and hydrodynamic
forces on SPM buoy from sea and connected tanker and design the mooring chains
in MATLAB
Evaluating the hydrodynamic loads and design of mooring lines and anchors for a
barge moored in lake by moses.
Editing the book “wave theory” written by dr.mohammad saeed seif, prof. at
school of mechanical engineering of Sharif University of technology.
Developing a computer code to extract characteristics of 3-component mooring
line considering elasticity in MATLAB
…
Current Research:
Experimental investigation of hydrodynamics of Amirkabir (GVA-4000M)
semisubmersible platform in simulated caspian sea environment.
Hydrodynamic and mooring lines analysis of Amirkabir platform by MOSES.
Experimental investigation of dynamic behavior of caissons of Persian gulf bridge
in simulated Persian gulf environment.
Presentations:
Sea-star TLP Tendon Stiffness Coefficients Matrix in Failure Conditions, spring
2013, 5th
Offshore Industries Conference.
Calculation of addedmass and damping for a two dimensional catamaran section
using boundary element method, winter 2012, 14th
Marine Industries Conference.
Conventional TLP modeling and analysis by MOSES, winter 2011, Sharif
University of Technology (SUT)
3. Experimental Investigation Of The Responses Of Semi-Submersible Platform
Subjected To Regular Waves, autumn 2014, 11th
International Conference on
Coasts, Ports & Marine Structures (ICOPMAS2014), Tehran
Work Experience:
Engineering member of marine engineering laboratory, school of mechanical
engineering, sharif university of technology. (October 2012 – now)
Published Book:
Mohammad saeed seif, Mohammad ali dastan, Ali Ahmadi, Mohammad mahdy
abaiee. “introduction of design and analysis of offshore structures”, Sharif
university of technology press, 2014.
Published papers:
J.Rashidi, A.Ahmadi, Experimental Investigation Of The Responses Of Semi-
Submersible Platform Subjected To Regular Waves, 11th International Conference
on Coasts, Ports and Marine Structures (ICOPMAS 2014), Tehran, Iran, 19-21
Nov. 2014.
M.M. Abaiee, A. Ahmadi, M.S. Seif, M.J Ketabdari, Discussion on an innovative
scenario for Transportation and Lowering Operation of 18000 tones Caissons of
Persian Gulf Bridge, 11th International Conference on Coasts, Ports and Marine
Structures (ICOPMAS 2014), Tehran, Iran, 19-21 Nov. 2014.
M.J. Ketabdari, M.M. Abaiee, A. Ahmadi, 3D Numerical Modeling of Wave
Forces on Tandem Fixed Cylinders Using BEM, Journal of Marine Science and
Application, Vol.12, Issue 3, pp 279-285, September 2013.
A.Ahmadi, M.J.Ketabdari, M.M.Abaiee, Calculation of added mass of surge,
heave and roll motions for sea star and conventional TLP using boundary element
method, 15th
Marine Industries Conference(MIC 2013), kish island, 29-31 October
2013.
M. Abbaspour, M.S. Seif, A. Ahmadi, Calculation of addedmass and damping of
two dimensional section of catamaran by BEM and investigation of wave
resonance between catamaran pontoons, 14th
Marine Industries Conference(MIC
2012), Tehran, 26-27 December 2012. (in Persian, oral presentation)
A.Ahmadi, M.M. Abaiee, M. Abbaspour, Investigation of Different Green
Functions to Determine Effective Matrix in BEM Applied in Hydrodynamic
Problems, 5th
Offshore Industries Conference (OIC 2013),Tehran, Sharif
University of Technology, 21-22 May 2013.
4. M.M. Abaiee, M.J Ketabdari, Time History of couple Heave, Pitch and Roll
Motions of Sea-star TLP in Regular Waves, 5th Offshore Industries
Conference (OIC2013),Tehran, Sharif University of Technology, May 2013.
A.Ahmadi, M.S. Seif, Static Analysis of Mooring Lines of SPM Oil Terminals, 5th
Offshore Industries Conference (OIC 2013),Tehran, Sharif University of
Technology, 21-22 May 2013.
M.M. Abaiee, A. Ahmadi, M.J Ketabdari, Sea-star TLP Tendon Stiffness
Coefficients Matrix in Failure Conditions, 5th
Offshore Industries Conference
(OIC 2013),Tehran, Sharif University of Technology, 21-22 May 2013.
A.Ahmadi, M.M. Abaiee, M.J Ketabdari, Numerical estimation of Sea-Star and
Conventional TLP’s Added Mass Coefficient using BEM, 15th marine industrial
conference(MIC 2013), 29-31 Oct. 2013.
M.M. Abaiee, A. Ahmadi, Hydrodynamic analysis of Two-Phase flow of a
circulation water channel using CFX package, 15th marine industrial
conference(MIC 2013), 29-31 Oct. 2013.
Submitted Papers (Under Review):
M.M. Abaiee, A. Ahmadi, M.J Ketabdari, Analytical Discussion on Stochastic
Hydrodynamic Modeling of Support Structure of HAWAII WTG Offshore
Wind Turbine, International Journal of Ocean System Engineering (IJOSE-
Korea), Submitted in the end of April-2014, ACCEPTED in Sep. 2014
M.M. Abaiee, A. Ahmadi, M.J Ketabdari, H. Alemi Ardakani, Numerical and
Experimental Study on Dynamic Behavior of Sea-Star TLP against Regular
Water Waves, Journal of Applied Mechanics and Technical Physics, Submitted
in the middle of April-2014,
Computer Software Familiarities:
Moses (Marine equipment structural and hydrodynamic analysis)
Maxsurf (Ship design)
Solid work (Geometrical Design of mechanical members)
Matlab (Mathematics workshop)
About M.Sc. Thesis:
‘PARADISE’ is name of computer code developed in MATLAB during my M.Sc.
program as final thesis. This code is consists of seven modules have certain task to finally
extract time history of conventional tension leg platform subjected to regular swell wave.
First order diffraction theory is the fundamental theory of thesis that is a result of
5. assuming sea environment as inviscid incompressible fluid and neglecting the
perturbation terms in governing equation and nonlinear terms in boundary condition of
problem. To extract the time history of motions, the dynamic equation of motion must be
solved. To reach to this purpose, we need added mass, damping and stiffness coefficients
and wave excitation forces and moments on TLP. Major task of ‘PARADISE’ is
computing the radiation added mass and damping, and wave excitation loads. This task is
done using second identity of green and a numerical approach (Boundary Element
Method). All meshes generated by ‘PARADISE’ are quadratic constant elements.
Effective matrices are calculated using Gauss-Legendre method. RAOs of motions are
calculated considering linear component of stiffness coefficients. Axial linear elastic
deformation of tendons is the basic assumption to calculate the Coefficients of stiffness
matrix. Nonlinear terms are considered in stiffness coefficients because of motion of
TLP. It’s the reason of nonlinearity of equation of motion, enforce us to use numerical
method, modified Euler method, to solve this equation. Stiffness coefficients, position,
velocity and acceleration of motion of TLP and change in tendon length are parameters
calculated in each time step.
Seven modules of ‘PARADISE’ are as below:
1. PARADISE: Designing and meshing the hull
2. PARADISE_NODES: Computing node position of each element
3. PARADISE_NORMAL: Extraction of normal vectors of elements
4. PARADISE_AREA: Calculating areas of elements and displacement of platform
5. PARADISE_DIFFRACTION: Calculating effective matrices, addedmass,
damping and wave excitation forces and moments. This module is expanded in 3
versions, each one use specific green function. The green functions used in this
versions are:
Fundamental solution of Laplace equation
Image green function
Noblesse green function
6. PARADISE_RAO: Extracting frequency response amplitude operator of TLP
7. PARADISE_MEM: Extracting time history of response of TLP, coupled with
nonlinear stiffness matrix in normal and tendon intact failure conditions.
Modified Euler Method is used in this module to computing nonlinear dynamic
ordinary equation.
• Finally the PARADISE was validated by MOSES and WAMIT for an oscillating
vertical cylinder. Related document is:
6. WAMIT-MOSES Hydrodynamic Analysis Comparison Study, JRME, July 2000.
PARADISE shows more similar results for Added mass, Damping and Wave exciting
forces and moments in comparison with those softwares.