similar to the throttle valve in most gasoline-powered cars. The butterfly vane rotates to vary the flow, turned by a small SG90 servo. A Wemos D1 Mini is used to run a pair of the valves ...

similar to the throttle valve in most gasoline-powered cars. The butterfly vane rotates to vary the flow, turned by a small SG90 servo. A Wemos D1 Mini is used to run a pair of the valves ...

Figure 1 shows how this can be done. A butterfly valve has a hollow stem conducting outside air into a number of small holes and dispersing the air into the water. This can only be done if the vapor ...