What is the Shower Curtain effect?

This happens when you turn on the water supply. The shower curtain can drift toward you while you are standing there.

It's a trivial fact that the shower curtain effect is also known as Bernoulli's principle. Swiss mathematician Daniel Bernoulli stated in Hydrodynamica (1738) that pressure decreases when there is more airflow. The shower's spray increases the airflow, decreasing pressure in the showering zone and causing the curtain to blow in.

What causes the Shower Curtain Effect?

Three possible explanations exist for the shower curtain effect. All three are based on differences in air pressure between the showering area and the non-showering one.

Air density variation

Warm water from your showerhead generates warm, humid air. This warm air rises up to the top of your shower and pours onto the curtain rod. This decreases the air pressure in the lower portion of the showering zone. The outside air, which is at a higher level of pressure, pushes the curtain toward the lower-pressure region. This effect is most effective when the water is warm. However, it can also occur with colder water.

Bernoulli's Principle

Showerhead sprays push air onto the curtain's inside, causing a decrease in pressure due to increasing velocity. This increases air velocity and decreases curtain pressure. The curtain will move inward when there is a pressure difference between the outside and the inside.

Bernoulli's Principle is a simple explanation for why aircraft lifts also play a significant role. Its wings are curved, so air flows faster up the sides, which reduces air pressure. The air also flows slower beneath, which increases air pressure.

Horizontal vortex

Shower spray forms a horizontal vortex. A mass of fluid revolves around the center axis, and this is called a horizontal vortex. A vortex is a type of tornado. The vortex's center is located in a low-pressure region. This helps explain why people and objects can become trapped inside a tornado.

In the shower, you will notice that the vortex created from the spraying of water is running perpendicularly to the curtain. The shower curtain is drawn in by the vortex's eye at low pressure.

Ways You Can Overcome the Shower Curtain Effect

Don't shower

• A relaxing bath can be used to calm down and clean up. No shower = no shower curtain effect.

Switch to heavier curtains

• Sometimes, the suction pressure of a shower vortex is too weak to lift heavier curtains. It is possible to leave a slight gap at one end rather than closing the curtain entirely.

Use suction cups and magnets to create a curtain

• Some shower curtains feature suction cups at their bottom, which you can push onto the sides and corners of the shower. There are also magnets on the bottom of some curtains, though these do not work with acrylic or fiberglass tubs.

Replace the showerhead

• Make sure your showerhead doesn't atomize too much water. A showerhead that sprays less water can reduce the airspeed inside the shower.

Install a new shower door

• If you find the shower curtain effect annoying, install a glass-framed shower door. Make a wet bathroom with no curtains or doors.

Install a low curtain pole

• A telescopic shower curtain rod can be used to block the lower portion of the curtain, which will prevent it from suckling in.

Use a string with a weight

• Attach a length of string to the weight and tie it around the curtain rod. The weight should be placed low against the curtains and not higher than the rims of the tub or shower pan.