radiator thermal valve in cars

It sounds like you want to steal someone's design for a valve.

If I were you I'd work on both my English and my ethics.

As someone who has spent many hours designing "things", I'm offended by your request.

Do your own design work!

of course not i just just don't know what to do or where to start,as you see its hard for a student to do such a work without any consultation,so don't be so hard on me

We don't do homework here, either.

Ask your instructor how to proceed. Once you have arrived at a design, post it here and there will be plenty of help.

I'll give you this piece of advice. First, determine what you want the device to do.

Good advice there. When you have the purpose well-enough defined, the rest will be easy.

i appreciat your advice, i think am confused some how,and don't know what to do, it's just i need some advices not to steal any one's work

http://auto.howstuffworks.com/cooling-system8.htm

http://www.familycar.com/Classroom/CoolingSystem.htm

"The heart of a thermostat is a sealed copper cup that contains wax and a metal pellet. As the thermostat heats up, the hot wax expands, pushing a piston against spring pressure to open the valve and allow coolant to circulate."

google 'principles of resource optimization'

As stated earlier, we do not do homework. This is not to be cruel, but part of the learning process is to do the work yourself.

Here though is a standard rule of thumb for what I call real world engineering.

1. Identify what the whole system is supposed to do, and what your part is supposed to do.
2. Identify what forces, or substances need to be controlled by your part in the system to achieve your goal.
3. Simulate your control to verify limits of control by either of these methods
1. Hand calculations
2. Computer simulations
4. Confirm suitability of your design from calculations or return to step 2.
5. Fabricate
6. Assemble test rig to verify fabricated part's functionality and test part's performance.
7. If part does not perform as anticipated,
1. Look for fabrication errors. If found correct and retest. Step 6
2. Review part's design, Step 2
8. Assemble test rig to verify system performance with part installed.
9. Install part in system.
10. Test system performance, if not acceptable return to step 2
11. Done

This may seem tedious, and once you've been down parts of this path more than once, you maybe tempted to bypass, but those are the times I've been burned.