Dear Dr: I am working in rainfall simulation under lab conditions, using a device developed by Kamphorst, Chagas an Irurtia and Mon, you can read my publications in relation with this issue. Best Regards

Dear, it depends on many different things such as required time step, runoff rate, duration of experiment, need for sampling etc. Usually, the simplest way is the manual one which consists in collecting the runoff and weighing it. There are of course many other possibilities which are more automated but it would be better if you specify more details about your experiments.

Hi Mahboobeh Kiani Harchegani; 

http://www.indianjournals.com/ijor.aspx?target=ijor:ijsc&volume=38&issue=2&article=005

Dear Miss Kiani

As I know what you are doing, your devices and you experiments, the simplest way is manual measurement using a bucket for a given time at different time intervals during each experiment, and then weighing it or measuring its volume.

Dear Mahboobeh,

that depends on the flow to measure/monitor. Is it continuously and steady or do you have high and low flow rates?

You might combine a tipping bucket with a logged balance. The balance measures the filling status and the tipping bucket emties itself every now and then depending on the flow rate. The advantage compared to the bucket is, that you can study the filling/run-off dynamics in detail but you do not have to empty the bucket manually.

http://www.hydrol-earth-syst-sci.net/15/1379/2011/hess-15-1379-2011.html

wish you a productive time!

Thomas

http://www.hydrol-earth-syst-sci.net/15/1379/2011/hess-15-1379-2011.html

It depend on purpose of your experiment and the parameters you may need. A tipping bucket with a logged balance is a good choice if continuous runoff rate, rainfall - runoff - soil erosion dynamics are needed.  A bucket with a scale meter or automatic gauges will tell you the time step runoff rate or rainfall-runoff process. 

Dear Mahboobeh,

You can use a runoff gauge that records the height of runoff and allows you to determine the variation of runoff flow versus time. The later is needed for rainfall-runoff and erosion studies.

Good luck.

Lamia.

Usually, when we did the same thing we used self-recording tipping bucket made by ourselves. You can refer to the rain gauge. The event recorder we used is HOBO event recorder (Onset Computer Corporation, MA, USA). It is not expensive. Good luck!  Zhao