REYNOLD’S APPARATUS

The apparatus consists of a glass tube with one end having a bell mouth entrance; connected to a constant head water tank, at the other end a valve is provided to vary the flow rate. The tank is of sufficient capacity to store water. A capillary tube is introduced centrally in the bell mouth for feeding dye from a small container placed at the top of the tank, through polythene tubing. By varying the rate of flow, Reynold’s number is changed. This also changes the type of flow. Visual observation of dye (Thread) will indicate the type of flow, which can be confirmed from Reynold’s number computed.
Present set-up is a self-contained water re-circulating unit, provided with a sump tank and a centrifugal pump, etc. The flow control valve and by-pass valve are fitted in the water line. A flow rate of water is measured with the help of a measuring cylinder and stopwatch.