Measuring and storing liquid flow

Hi folks,

I need to measure the flow of a liquid (with water like properties) in a relatively small tube (4-5 mm diameter). I need to store the measurements plus time stamp to be transfected wirelessly to a computer every once in a while. I would appreciate if anybody give me an idea what Arduino parts I need to use (sensor to measure the liquid flow, IC, memory unit and wireless module). I have no idea about electronics, but very eager to learn.

Cheers

recently there was a similar request but for oil, might be instructive - http://arduino.cc/forum/index.php/topic,91290.0.html -

My water injection system uses a small turbine to measure water speed in a hose roughly that size. Perhaps you could use something similar? I haven't investigated how it works, but I guess it's got a sensor detecting the vanes moving past.

What sort of accuracy and resolution do you need for the flow measurements?

How many measurements do you need to be able to buffer, and how long do you need to buffer them for?

How accurately do you need to timestamp them?

How long is the whole system expected to keep running continuously?

Thanks for your reply PeterH

In terms of volume accuracy, I do not need to go beyond milliliters. Device should be able to log at least 100 measurements per day and keep information information for about a month. Water does not flow continuously. It happens at different times and for short time spans from 3 to 10 seconds.

I am planing to modify an existing device which has a 4mms hose, therefore I prefer a measuring method that doesn't require an in-hose part.

Cheers