I suggest you to define your theme as clearly as possible. It is said that the right formulated aim is about fifty one percent of success.
It would be great and very helpful to have and study a full PhD-paper written earlier by a pupil of your advisor. There is no something bad in it. Thereby you can understand the volume of work you have to do in order to gain a PhD-degree.
From Wikipedia I have read about multiphase flow. Do you able to choose concrete material to research independently or is it up to your advisor? What is about conditions of the flow? Where your materials will flow, so to say? You have to decide it clearly.
What is the scientific problem your research advisor works on at the moment? Is it possible for you to intersect your research with his one?

My doctorate research was about the influence of silicon on plant growth and protection against fungi.
Before I started the work I had made a research proposal.
The first paragraph of it contained a problem statement. In my case: nowadays in order to gain rich crop a lot of chemicals need to be used. This fact is very harmful not only for the humanity but also for the nature. Because of this more natural-friendly fertilizers need to be developed. (The real statement was more complicated but sense was in it).
Then it included the title (the theme) of the research, and tasks (aims) that should be done during the research. For example: to define the influence of various natural silicon compounds on plant growth and development; to pin down the reactions of silicon uptake from the soil and to describe it closely.
A practical application of my research was described below. It is important because the results I had taken are useful for agriculture. Without practical application all research is only waste of money, time etc. (in my opinion).
Another important part of the proposal is to put forward a hypothesis you will defend. In my case: silicon in active form taken by plant is able to protect plant cells from pathogen fungi and increases plant growth.
My entire research proposal was written in three pages.
Please say me about the methods of your research. Are they needed special equipment? Or are you able to do it with help of math only? In any cases I suggest you to use standard methodology that is commonly used in your branch of science. It also depends on the laboratory facilities your adviser has. To choose appropriate methods of research read the special books. (You need to go to the library). Remember that you first aim is to gain an appropriate research data because it gives proofs for your theory.
It you have another questions please ask me.

In order to find your specific theme of investigation try to examine actual research papers in computational fluid dynamic. Doing it you, most probably, will be able to determine an interesting problem to analyze. In other words attempt to study what had been done in your area before and what authors suggest to do further. Ask yourself about what questions in fluid dynamic are not studied yet.

Do you have a research plan that is approved by your scientific advisor?
In my opinion the success in doctorate investigation means data gathering according to the program of research. Do you have it?

Hello!
I took PhD in chemistry in Germany and I feel that my scientific adviser was a very good guy in all respects. Because of this fact I think that there are next criteria of a good adviser:
1. Scientific advisor should be very proficient in the area that he administrates;
2. He should to control every step of research work of his pupil. If the pupil is in difficulty a good research advisor immediately comes to the aid of.
3.Since a research advisor prepares new scientists he must be easy to get in touch with and be able to find common language with his pupils.
First stage of any scientific work is the making statement of the theme and aims of research, selection of appropriate research conditions and techniques. This all should be approved and endorsed by your adviser. It is inadmissible and very risky to do research without the plan that was agreed by the advisor. In order to successfully defend your thesis your research work has to meet certain requirements.
3. During the research work an advisor must control the data that his pupil obtains. He has to be sure that the data are adequate and fully corresponded to the research plan.
I would like to state a couple of questions to you:
Do you have a research plan coordinated with your scientific advisor?
Does your advisor concern about your achievements and difficulties?

Hello!
Please, tell us a bit about your research. What is the theme?

My suggestions are:
First: to determine which branch of science you are interested in;
Second: to find an appropriate scientific adviser (professor);
Third: to think about funding for your research project and also living costs.

Hello!
I am Alexey, 31, a college teacher. I took a PhD degree on chemistry and molecular biology in Germany. Since 2012 I have been carrying on courses in chemistry for senior high school children in Russia. The main aim of the courses is a preparation to the Unified state exam. The lessons are arranged both in person and distantly so the school children who are from remote (rural) areas are able to take the part. During the classes we spend most of the time on solving practical problems (investigate various reactions, calculate reactants and final products, chemical kinetics and others). The classes have tangible effect on the school results of the children who are involved in ones.
Now I plan to arrange such courses for foreign school children. At first the amount of participants would not be more than ten. My primary aim here is taking a practice experience and to understand differences between Russian and foreign study programs.
I would like to take answers on the following questions:
1. Is there a demand in such lessons outside Russia?
2. What is your personal attitude to the distant education?
3. How can I find participants?
Thank you in advance!