MOBILE FLUID EXPULSION DEVICE

Abstract

An apparatus and method are provided for expelling a fluid, including vapor and liquid sprays. A spray is expelled at high velocities from a heated chamber via an exit valve. The chamber includes a flow member or structure that directs and controls the flow of the fluid from an inlet orifice to an outlet orifice along a non-linear path. This prevents the liquid from moving in a wave motion within the chamber if the apparatus is moved.

Claims

1. Apparatus for expelling a fluid comprising; a reservoir for storing the fluid; a chamber; an inlet orifice to the chamber; an inlet valve; an outlet orifice from the chamber; an outlet valve; at least one heater to heat the fluid within the chamber, such that a temperature and a pressure of the fluid are raised when the inlet valve and outlet valve are closed, causing at least a portion of the fluid within the chamber to change state; a flow member to direct and control a flow of fluid from the inlet orifice to the outlet orifice along a non-linear path; and whereby in use, fluid is expelled from the outlet orifice of the chamber by a vapor explosion process.

2. The apparatus according to claim 1, where the inlet valve and the outlet valve each comprise a valve actuator and a valve seat.

3. The apparatus according to claim 1, where the at least one heater is arranged to raise the temperature of the fluid to a value equal to or greater than a saturation temperature of the fluid at ambient pressure.

4. The apparatus according to claim 1, wherein the at least one heater comprises a heating element arranged in or near the chamber to heat the fluid in the chamber.

5. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid along the non-linear path from the inlet orifice to the outlet orifice causes a minimum of 90° of change to a direction in which the fluid was travelling.

6. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid along the non-linear path from the inlet orifice to the outlet orifice causes a minimum of 270° of change to a direction in which the fluid was travelling.

7. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid along the non-linear path from the inlet orifice to the outlet orifice comprises at least one non-linear channel.

8. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path comprises a plurality of non-linear channels.

9. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path comprises at least one channel having a series of bends which cause the fluid to change direction several times.

10. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path comprises at least one baffle arranged to cause the fluid to change direction.

11. The apparatus according to claim 1, where the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path (13) comprises a series of baffles arranged to cause the fluid to change direction several times.

12. The apparatus according to claim 1, where the flow member that direct and controls the flow of fluid from the inlet orifice to the outlet orifice comprises at least one helical or spiral channel.

13. The apparatus according to claim 1, where the at least one heater is external to the chamber.

14. The apparatus according to claim 1, where the at least one heater is internal to the chamber, and the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path is positioned proximal to the at least heater.

15. The apparatus according to claim 1, where the at least one heater is internal to the chamber, and the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path is external to the at least one heater.

16. The apparatus according to claim 1, where the at least one heater is internal to the chamber and the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path is positioned within the at least one heater, where the flow of fluid is in fluid isolation from the at least one heater.

17. The apparatus according claim 1, where the at least one heater is arranged such that the at least one heater is also the flow member that directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path.

18. A method for expulsion of a fluid from a chamber, comprising: supplying fluid from a reservoir to the chamber via an inlet orifice by opening an inlet valve to the chamber; directing the fluid inside the chamber to flow via a non-linear path to an outlet orifice via an outlet valve; whilst the fluid is inside the chamber and the inlet and outlet valves are closed, heating the fluid to a temperature which is equal to or greater than a saturation point of the fluid at atmospheric pressure, such that at least a portion of the fluid changes state; and opening the outlet valve such that fluid is expelled from the outlet orifice by a vapor explosion process.

19. The method as claimed in claim 18, where the inlet valve and outlet valve each comprise a valve actuator and a valve seat.

20. The method as claimed in claim 18, where the fluid is heated by a at least one heater arranged in or near the chamber.

21. The method as claimed in claim 18, where a flow member directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path and causes a minimum of 90° of change to the direction in which the fluid was travelling.

22. The method as claimed in claim 18, where a flow member directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path and causes a minimum of 270° of change to the direction in which the fluid was travelling.

23. The method as claimed in claim 18, where the fluid is directed from the inlet orifice to the outlet orifice via at least one non-linear channel.

24. The method as claimed in claim 18, where the fluid is directed from the inlet orifice to the outlet orifice via a plurality of non-linear channels.

25. The method as claimed in claim 18, where the fluid is directed from the inlet orifice to the outlet orifice via at least one channel having a series of bends which cause the fluid to change direction several times.

26. The method as claimed in claim 18, where the fluid is directed from the inlet orifice to the outlet orifice via at least one helical or spiral channel.

27. The method according to claim 18, where a flow member directs and controls the flow of fluid from the inlet orifice to the outlet orifice along the non-linear path and comprises at least one baffle arranged to cause the fluid to change direction.

28. The method as claimed in claim 18, where the fluid may be directed from the inlet orifice to the outlet orifice via a plurality of non-linear channels which are positioned proximal to a heating element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The disclosure will now be described by way of example, with reference to the accompanying drawings:

[0059] FIG. 1 is a cross-sectional view of an example of a fluid expulsion device according to the present disclosure.

[0060] FIG. 2 is a cross-sectional view of another example of a fluid expulsion device according to the present disclosure.

[0061] FIG. 3 is a cross-sectional view of another example of a fluid expulsion device according to the present disclosure.

[0062] A cross-sectional view of an example of a fluid expulsion device is provided in FIG. 1. The fluid flows in the direction of the arrow, towards the chamber 1 via inlet orifice 2, when the inlet valve 3 is opened by the inlet valve actuator 4.

[0063] A cross-sectional view of an example of a fluid expulsion device is provided in FIG. 2. The fluid flows in the direction of the arrow, towards the chamber 1 via inlet orifice 2, when the inlet valve 3 is opened by the inlet valve actuator 4.

[0064] A cross-sectional view of an example of a fluid expulsion device is provided in FIG. 3. The fluid flows in the direction of the arrow, towards the chamber 1, via inlet orifice 2, when the inlet valve is open.

DETAILED DESCRIPTION

[0065] An embodiment of a fluid expulsion device according to this disclosure is illustrated in FIG. 1. A fluid is supplied from a reservoir (not illustrated) into a chamber 1 via an inlet orifice 2. The fluid which is supplied through the inlet is preferably a liquid. The liquid or foam could also include suspended entrained particulate solids. The liquid could be a solution comprising a solvent and a solute. Preferably, the fluid is pumped from the reservoir to the chamber 1.

[0066] The inlet orifice 2 and inlet valve 3 are arranged to allow a portion of fluid into the chamber 1 via an associated inlet pipe, tube, or channel from the reservoir. The fluid passes through the inlet orifice 2 when the inlet valve 3 is in the open position. The inlet valve 3 of FIG. 1 comprises a valve actuator 4 and a valve seat 5. The valve actuator 4 may be connected to a controller (not illustrated). In the embodiment illustrated in FIG. 1, the inlet actuator 4 is spaced from the inlet orifice 2 due to the use of a pintle or rod 6 connecting the valve actuator 4 to the valve seat 5. The inlet valve 3 is opened to allow fluid to enter the chamber 1 until the chamber 1 contains a predetermined quantity of fluid. When the predetermined quantity of fluid has entered the chamber, the inlet valve 3 is closed by the inlet valve actuator 4.

[0067] A separate outlet orifice 7 is provided at another location in the chamber 1. The outlet orifice 7 is opened or closed using outlet valve 8. Opening the valve 8 allows fluid to be ejected from the chamber 1, whilst closing the valve 8 allows fluid to be sealed in the chamber 1. The outlet valve 8 comprises an outlet valve actuator 9 and a valve seat 10. In the embodiment illustrated in FIG. 1, the outlet valve actuator 9 is spaced from the outlet orifice 7 due to the use of a pintle 11 which connects the outlet valve actuator 9 to the valve seat 10.

[0068] The chamber 1 further includes a flow member or structure 12 to direct and control the flow of fluid from the inlet orifice to the outlet orifice along a non-linear path 13. The flow member or structure 12 to direct and control the flow of fluid is a component arranged to redirect the flow of the fluid within the chamber 1, such that the fluid is forced to change direction several times when travelling between the inlet orifice 2 and the outlet orifice 7.

[0069] In FIG. 1, the flow member or structure 12 is an element having a helical shape which forces the fluid towards the outer periphery of the chamber 1. The fluid may travel inwards towards the center of the chamber 1 in the gaps between the helically shaped protrusions from the element; and may travel outwards towards the periphery of the chamber 1. This may create a flow path which oscillates in respect of the direction of travel. Alternatively, a series of baffles could be used in place of the helical element. The fluid is unable to travel in a linear fashion from the inlet orifice 2 to the outlet orifice 7 due to the obstruction at the inlet orifice 2 and outlet orifice 7 caused by the element. The flow member or structure 12 acts to increase the foam concentration in the vicinity of the outlet orifice 7, by preventing the break-up or destruction of foam by the liquid in the chamber.

[0070] The fluid is heated inside the chamber 1 using a heater, with the inlet 3 and outlet valves 8 being closed. The heater 13 can be located within the chamber or can be external to the chamber. In the embodiment demonstrated in FIG. 1, the heater 14 is an external heating jacket, but as explained above, alternative heaters can also be used.

[0071] Closing the inlet 3 and outlet 8 valves prevents the escape of fluid. Heating the fluid in the chamber causes an increase in the pressure within the chamber 1 and hence also a further temperature increase. The temperature can be monitored by one or more temperature sensors (not shown) which may be fitted inside the chamber 1 or near to the chamber 1, for example in the inlet stream, or on a wall of the chamber 1.

[0072] The pressure can be monitored by one or more pressure sensors (not shown), such as pressure transducers, which may be located in the chamber 1. The outlet valve 8 may be arranged to open after a specified amount of time. The outlet valve 8 can be controlled by a controller (not shown) such that the outlet valve 8 will not open when the pressure is below a specific predetermined pressure. Alternatively, the outlet valve 8 can be controlled such that the outlet valve 8 will not open when the temperature is below a specific predetermined temperature.

[0073] The sudden release of pressure when the fluid exits the outlet orifice 7 causes a vapor explosion due to the rapid expansion of liquid, foam and/or vapor. The outlet orifice 7 may be optionally connected to a nozzle (not shown) which can be used to alter the dispersion properties of the spray and to further decrease the droplet size of the liquid in the spray.

[0074] The device is able to produce vapor or mist in short sharp bursts; the volume of vapor released corresponds to the amount of fluid which is fed into the chamber 1. As fluid is expelled from the chamber 1, the pressure within the chamber 1 drops. The outlet valve 8 can be arranged to close when the pressure has dropped back to an ambient or second predetermined pressure, which may be referred to as the closure pressure. Alternatively, the outlet valve 8 can be arranged to close once the temperature has returned to a predetermined temperature. The outlet valve 8 may be arranged to close after a specific amount of time has passed.

[0075] A controller can be programmed such that it closes the outlet valve 8 when a predetermined closure pressure is reached and opens the inlet valve 3 again to introduce new fluid into the chamber 1. The system can cycle between introducing new fluid into the chamber 1 and expelling the fluid from the outlet orifice 7. The controller can be used in combination with the valve actuators 4,9 to control a rapid cycle of expelling the fluid and admitting new fluid into the chamber 1. Alternatively, the controller can be programmed to open the valves according to a timing sequence, where the valves 3,8 are opened and closed for a predetermined time, provided that a set (predetermined) pressure or temperature has been reached or exceeded. The valve timing can be offset, such that the inlet valve can be open for longer, followed by several rapid openings of the outlet valve. The timing sequence chosen for the valve will depend on the specific application for the device.

[0076] A further embodiment of the disclosure is illustrated in FIG. 2. This embodiment is similar to the embodiment illustrated in FIG. 1, except that the valves are not spaced from the inlet and outlet orifices. The numbering and description provided above for FIG. 1 applies to FIG. 2, with the only difference being that the outlet valve actuator 9 is located downstream from the chamber 1, and proximal to the outlet orifice 7.

[0077] In FIG. 3, an embodiment of the disclosure is illustrated, where the chamber 1 is exposed to movement along a single axis and a baffle 15 is used to induce a 180° change in the direction of flow of the fluid from a first side of the baffle 15a to the second side of the baffle 15b. If the chamber is cylindrical, the baffle may be concentric.

[0078] In the embodiment of FIG. 3, the inlet and outlet (2,7) orifices are offset. The fluid flows through the inlet valve 3 and into chamber 1. The inlet valve 3 comprises a valve actuator 4 and a valve seat 5. In the embodiment illustrated in FIG. 3, the inlet valve actuator 4 is spaced from the valve seat 5 by a pintle 6. Once inside the chamber 1, the fluid has to go through 180° of change in order to pass over baffle 15. Any foam which is formed on the second side of baffle 15b is protected from the movement of liquid on the first side of the baffle 15a, even if the chamber 1 is exposed to movement. This maximizes the probability that foam will be present at the outlet orifice 7. The fluid within the chamber 1 is pressurized and heated past the saturation temperature of the fluid at atmospheric or ambient pressure. The fluid is then rapidly expelled by a vapor explosion process through the outlet orifice 7 when the outlet valve 8 is opened. The outlet valve 8 comprises an outlet valve actuator 9 and an outlet valve seat 10.

Experimental Results

[0079] In this test, the influence of adding a spiral insert into the chamber was tested. The influence on the performance of the system across varying orientations was measured. In this experiment, the spiral insert directs and controls the flow of fluid along a non-linear path from the inlet orifice to the outlet orifice.

[0080] Running the system at a constant power setting (600 W) and flow rate (1 g/s), we ran the system whilst varying the orientation of the chamber (and outlet orifice) such that the angle of the spray was varied 30 degrees at a time. Water was used as the operating fluid in all the experiments. The same pressure (3.8 bar) and temperature (150° C.) of the chamber was used for all of the experiments. All conditions other than the insertion of the spiral, and the angle of the spray were kept constant.

[0081] Starting in a horizontal position the system was operated such that water was sprayed for 5 minutes from which an average droplet size was measured. The system was then rotated 30 degrees in a clockwise direction, such that the orientation of the chamber was changed, and the resulting spray direction was now pointing downwards. Again, the system was operated such that water was sprayed for 5 minutes from which an average droplet size was measured. The system was then rotated a further 30 degrees in a clockwise direction so that the spray direction was now pointing in a 60 degrees downward orientation. Water was sprayed for 5 minutes from the outlet orifice and an average droplet size was ascertained from the data collected. The same measurements were repeated at 30° intervals of rotation until the system was back in the original orientation.

[0082] The same set of measurements were taken for the system with and without the spiral insert in the chamber. The table below shows a comparison of the results obtained from each system. It also illustrates the difference in spraying quality which is obtained by using the inserted spiral when spraying across multiple orientations.

TABLE-US-00001 System Without System With Insert: Avg. Insert: Avg. Droplet Diameter Droplet Diameter Orientation (μm) (μm) Horizontal 23.4 23.8 30° Down 24.1 24.0 60° Down 178.0 24.0 90° Down 246.8 24.4 60° Down Upside-down 181.2 23.9 30° Down Upside-down 24.0 24.3 Horizontal Upside-down 23.7 23.9 30° Up Upside-down 23.6 23.6 60° Up Upside-down Spraying is irregular 23.9 90° Up Spraying practically stops 23.8 60° Up Spraying is irregular 23.7 30° Up 24.2 23.8

[0083] The results show a far more consistent spray performance from the system according to the present disclosure with the insert present in the chamber, when compared to the same system without an insert.

[0084] Although various embodiments have been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the true scope and content of this disclosure.