Nutrient film device and nutrient film technique hydroponic system
A nutrient film technique hydroponic system includes a growing tower, a nutrient film generator, and a nutrient reservoir configured to hold a supply of nutrient liquid. The nutrient film generator converts a flow of nutrient liquid from the reservoir into a nutrient film flowing along an inner surface of the growing tower. Methods for cultivating plants in a hydroponic system are provided.
1 . A nutrient film technique hydroponic system for cultivating plants comprising:
a growing tower having a cylindrical sidewall at least partially defining a hollow interior, an inlet into the hollow interior at an upper end of the growing tower, and a plurality of planting ports in the cylindrical sidewall, wherein the plurality of planting ports are below the inlet and open to the hollow interior;
a tower axis extending axially through the hollow interior;
a pump configured to supply nutrient liquid to the inlet of the growing tower; and
a nutrient film generator at the upper end of the growing tower configured to convert a flow of nutrient liquid into a nutrient film flowing axially and radially, relative to the tower axis, along an inner surface of the cylindrical sidewall of the growing tower, the nutrient film generator comprising:
a nutrient liquid inlet through which nutrient liquid is introduced to the nutrient film generator in a substantially axial direction along the tower axis, wherein the tower axis passes through the nutrient liquid inlet; and
a swirler aligned with the tower axis and comprising a plurality of circumferentially spaced static vanes, the swirler configured to induce a swirl on the nutrient liquid passing through the swirler to turn a flow direction of the nutrient liquid from being substantially axial along the tower axis to including a tangential component that directs the nutrient liquid both circumferentially and radially with respect to the tower axis.
2 . The nutrient film technique hydroponic system of claim 1 , comprising a reservoir configured to hold a supply of nutrient liquid, wherein the reservoir is fluidly coupled to the nutrient film generator by a flow path including the pump.
3 . The nutrient film technique hydroponic system of claim 2 , wherein the growing tower comprises an outlet from the hollow interior at a lower end of the growing tower, wherein the outlet drains into the reservoir, wherein the pump is a recirculation pump mounted within the reservoir to recirculate nutrient liquid from the outlet back to the inlet of the growing tower.
4 . The nutrient film technique hydroponic system of claim 3 , wherein the flow path includes a conduit having an inlet end fluidly coupled to an outlet of the pump and an outlet end in fluidic communication with the inlet of the growing tower via the nutrient film generator, wherein the conduit comprises at least one conduit section extending generally parallel to the tower axis.
5 . The nutrient film technique hydroponic system of claim 3 , comprising an aerator fluidly upstream of the swirler, wherein the aerator is configured to inject air into the flow of nutrient liquid before the flow of nutrient liquid reaches the swirler.
6 . The nutrient film technique hydroponic system of claim 2 , wherein the reservoir comprises an open-topped container and a lid for the open-topped container, wherein the lid comprises a tower base engaging with a bottom end of the growing tower and configured to support the growing tower in a generally vertical orientation.
7 . The nutrient film technique hydroponic system of claim 1 , wherein:
the plurality of planting ports are spaced about a circumference of the cylindrical sidewall and include at least a first planting port on a first side of the cylindrical sidewall, a second planting port on a diametrically-opposed second side of the cylindrical sidewall, and a third planting port vertically spaced above the first and the second planting ports.
8 . The nutrient film technique hydroponic system of claim 1 , comprising at least one grow pot, the at least one grow pot removably mounted in one of the plurality of planting ports, the at least one grow pot capable of receiving plant grow media.
9 . The nutrient film technique hydroponic system of claim 1 , comprising:
a user interface interconnecting a power source and the pump, the user interface configured to regulate an operation of the pump; and
a duty cycle timer interposed between the power source and the pump, wherein the duty cycle timer controls a duty cycle of the pump and thereby controls the flow of nutrient liquid to the growing tower;
wherein the duty cycle has a pump-off time and a pump-on time, and the user interface comprises an input control that varies at least one of the pump-off time and the pump-on time.
10 . The nutrient film technique hydroponic system of claim 1 , wherein:
the nutrient film generator comprises a casing having the nutrient liquid inlet, and the swirler is at the nutrient liquid inlet; and
the casing comprises a substantially horizontal upper wall curving to meet a substantially vertical sidewall to transition the flow direction of the nutrient liquid from including the tangential component to a helical swirling flow stream that flows along the inner surface of the cylindrical sidewall of the growing tower.
11 . The nutrient film technique hydroponic system of claim 10 , wherein the casing comprises:
a first diameter at the nutrient liquid inlet, the first diameter taken along a plane perpendicular to the tower axis and passing through the nutrient liquid inlet; and
a second diameter at the substantially vertical sidewall, the second diameter taken along a plane perpendicular to the tower axis and passing through the substantially vertical sidewall;
wherein the second diameter is greater than the first diameter.
12 . The nutrient film technique hydroponic system of claim 11 , wherein the growing tower has a third diameter at the cylindrical sidewall taken along a plane perpendicular to the tower axis and passing through the cylindrical sidewall, where the third diameter is greater than the first diameter.
13 . The nutrient film technique hydroponic system of claim 1 , comprising an aerator fluidly upstream of the swirler, wherein the aerator is configured to inject air into the flow of nutrient liquid before the flow of nutrient liquid reaches the swirler, wherein the aerator is a venturi driven aspiration aerator that is in series with and directly upstream of the swirler.
14 . The nutrient film technique hydroponic system of claim 1 , comprising a plurality of other growing towers, wherein the pump supplies nutrient liquid to each of the plurality of other growing towers.
15 . A method for cultivating plants in a hydroponic system, the method comprising:
providing a growing tower having a cylindrical sidewall at least partially defining a hollow interior, a tower axis extending axially through the hollow interior, an inlet into the hollow interior at an upper end of the growing tower, an outlet from the hollow interior at a lower end of the growing tower, and a plurality of planting ports in the cylindrical sidewall, wherein the plurality of planting ports are below the inlet and open to the hollow interior;
supplying nutrient liquid from a reservoir to the inlet of the growing tower;
generating a nutrient film within the growing tower by accelerating the nutrient liquid tangentially and inducing the nutrient liquid to flow axially and radially, relative to the tower axis, along an inner surface of the cylindrical sidewall as a nutrient film; and
collecting runoff nutrient liquid that exits from the outlet of the growing tower within the reservoir.
16 . The method of claim 15 , wherein:
supplying nutrient liquid from a reservoir comprises pumping nutrient liquid from the reservoir to a swirler at the inlet of the growing tower, the swirler comprising a plurality of vanes; and
generating the nutrient film comprises accelerating the nutrient liquid tangentially with the swirler.
17 . The method of claim 16 , comprising injecting air into the nutrient liquid with an aerator before the nutrient liquid reaches the swirler.
18 . A nutrient film technique hydroponic system for cultivating plants comprising:
a growing tower having a tower sidewall at least partially defining a hollow interior, an inlet into the hollow interior at an upper end of the growing tower, and a plurality of planting ports in the tower sidewall, wherein the plurality of planting ports are below the inlet and open to the hollow interior;
a tower axis extending axially through the hollow interior;
a pump configured to supply nutrient liquid to the inlet of the growing tower; and
a nutrient film generator at the upper end of the growing tower that converts a flow of nutrient liquid into a nutrient film flowing along an inner surface of the tower sidewall of the growing tower, the nutrient film generator comprising:
a casing having a nutrient liquid inlet, an upper wall extending radially from the nutrient liquid inlet, and a casing sidewall extending downwardly from the upper wall, wherein the tower axis passes through the nutrient liquid inlet; and
a swirler configured to induce a swirl on the nutrient liquid passing through the swirler to turn a flow direction of the nutrient liquid from being substantially axial along the tower axis to including a tangential component;
wherein the casing has a concave inner surface where the upper wall meets the casing sidewall to transition the flow direction of the nutrient liquid from including the tangential component to a helical swirling flow stream that flows along the inner surface of the tower sidewall.
19 . The nutrient film technique hydroponic system of claim 18 , wherein the casing comprises:
a first diameter at the nutrient liquid inlet, the first diameter taken along a plane perpendicular to the tower axis and passing through the nutrient liquid inlet;
a second diameter at the casing sidewall, the second diameter taken along a plane perpendicular to the tower axis and passing through the casing sidewall, wherein the second diameter is greater than the first diameter; and
a third diameter at the tower sidewall taken along a plane perpendicular to the tower axis and passing through the tower sidewall, wherein the third diameter is greater than the first diameter.