FIELD OF INVENTION:
The present innovation relates to device which reduces pressure and flow-rate in a fluid flow pipeline of any geometrical shape and size/cross-sectional area. There are situations where pressure is high which lead to high flow-rate in normal circumstances, but requirements are of pre-decided low flow-rate.
BACKGROUND:
It has been observed that in many situations the volumetric flow-rate is unmanageably and unwarrantedly high due to high pressure at the outlets resulting in loss of energy and mass. In case of high pressure, the desired flow-rate is never achieved at the outlets and at many times, it has been observed that there is non-uniform distribution of volume flow within the same network or point. For example, in case of high rise buildings, it is noticed that one outlet at a particular floor gets more water than the other outlet at a different floor or same floor taps draw different flow-rates due to high pressure heads.
PRIOR ART:
Exhaustive literature search was carried out world over to search devices/valves which can provide a constant flow-rate at high pressure in pipeline. For such situations, the invented device reduces the high pressure as well as gives low constant flow-rate. There is no such device/valve available in the world which will simultaneously reduce pressure and flow-rate. There are however some highly complex and expensive valves which are unable to reduce pressure but can control the flow-rate. Such valves are designed for industrial applications and arc very expensive and have complex configurations. These valves do net do exactly same function, but can be considered closer to the present invented device. Such valves have been described below. Some complex functioning geometry and expensive flow control devices are available in USA/Europe as given below. The invented pressure and flow control device is all to
gather different in terms of geometry and flow characteristics. In the known arts, the other pressure reducing and flow controlling valves are:
1) Pressure Reducing Valves ( PRVs ): These devices are installed at the up stream of the pressure sensitive equipments. These valves reduce water pressure to the desired level at flow as well as no-flow (drop tight) conditions. A common mistake is to confuse pressure reduction with flow-rate control. It is true that if pressure in a system is reduced, the maximum flow-rate from any given outlet will be reduced, although the reduction in volume may not be visible or even noticeable. Therefore, flow rate could only be controlled by using a flow-controlling device, and it can not be controlled by PRVs
2) Flow Control Valves: Flow control devices are the devices which control the flow rates in the system. These flow-rate control devices are:
a) Tapered-tvpe Flow-rate Control Valve: Tapered-type flow control valve for household service connections is available in Chennai, India. This is in use in certain parts of India. Many times, there is illegal drawl of water from the distribution system by way of using small electrical driven motors in consumer connections. To check this menace, a" mini flow control valve in the form of tapered ball drive system fixture fitted with a float ball has been developed and successfully used. This controls and maintains service connection flow, even with supply hours ranging barely between 1-2 hours a day. It allows only designated flow 5 Ipm (at very low pressures 0.1 kgf/cm ) or 10 Ipm or 15 Ipm or 20 Ipm or upto 25 Ipm (at very high pressures > 0.6 kgf/cm ) in the house service line beyond it's location irrespective of the incoming higher quantity of flow in the line.
This valve has been designed on the basis of float principle, to control the maximum drawl from the main line by consumer and it is to be installed between ferrule and water meter. The valve may be installed below or above the ground level. The valve carries a stainless-steel ball of designed weight. The ball moves up and down in accordance to the available pressure at the upstream of valve, when pressure is low « 0.1 kgf/cm (1 m water column), the ball moves little bit. And for higher pressures upto « 0.6 kgf/cm (6 m water column), the ball rises to higher appropriate level and allows
increased flow-rate in the range of 5 Ipm to 20 Ipm. When the pressure exceeds 6 m water column, the condition becomes comparable with a situation of using electric suction motor, the designed flow takes place through notch space only, as the ball rises to the maximum level and allows flow rate upto 25 Ipm. The tapered-type flow-control valve for house hold service connections is unsuitable and can not be used for controlling the flow rate in tall buildings as pressures are in much higher range and beyond its operational range.
Other demerits of this valve are: (i) The device has been developed for a specific purpose and is unsuitable to control the flow rate in tall buildings, because the static pressure is always more than the 6 m water column (except for top two storeys). This means that the valve shall always provide the flow fate > 20 Ipm, which is much above the normal flow rate requirements, (ii) More over, the valve carries a floating stainless steel ball, which will rotate inside the valve-casing due to high turbulence flow pattern and will cause damage to itself and its surroundings as well as the inner surface of the valve. This process will make the cavity and the ball ellipsoidal shape and eventually, the distorted ball and its unmatched cavity will change its flow rates from the designed ones. Thus, the tapered type flow control valve is unsuitable for controlling the flow rates in situations of varied pressures. On the other hand, the new invented device can be used to control the flow-rate under wide pressure ranges and as well as to limit the maximum drawl from the water main to household connection, b) Other Flow Rate Control Devices in use in USA/Europe: Various types of flow control valves in use in USA/Europe are: Solenoid Valves, Mini-Flo Automatic Flow Rate Controller, Kates F.C.Valve, Salvair Direct Acting Ratio Blend Controller, Flo-Miser Flow Rate Controller, I/Q Valve, PVC Automatic Flow Rate controller, D Q Valve, etc. Some of these valves are described below:
i) Solenoid Valves: Solenoid valves are used when fluid flow (air/liquid) is to be controlled automatically. It is generally used for air flow control. These are increasingly used in the most varied types of plants and equipments. These valves are control devices which, when electrically energized or de-energized, will either shut-off or allow air to flow. Valve actuator functions as an electromagnet. When energized, a
magnetic field builds up which pulls a plunger or pivoted armature against the action of a spring. When de-energized, the plunger or pivoted armature is returned to its original position by the spring force. This valve will start or stop the flow, and no other control.
ii) "Kates" Flow Control Valve (KFC Valve): The KFC valve has been applied successfully in industry to a wide variety of liquid and gas applications. Working of this KFC Valve: Flow rate through an orifice is proportional to the size of the restriction and the differential pressure across it. By combining an adjustable orifice with an internal regulating valve, the Kates controller will maintain a constant pressure drop across the metering orifice. Pressure equation: P/ = P2 + Spring Force. For example: if supply pressure {Pi) increases, the resulting momentary pressure imbalance immediately will move the impeller downward. This action restricts the valve ports thus increasing orifice backpressure (P2), restoring differential pressure and the flow rate to the original settings. The unit will respond equally as well to an upset in outlet pressure (P3).
iii) Flo-Miser Flow Rate Controller: The Flo-Miser is an economical, lighter duty version (SS body with Teflon body seals) of standard flow rate controllers. It offers much of the same flow characteristics as of high performance Kates Flow-Rate Controllers at a substantially lower cost. The Flo-Miser combines a characteristic needle valve with an internal differential pressure regulating valve. By controlling the pressure drop across the adjustable orifice, flow rate will always remain constant. Since the control portion is immersed in the fluid and its controlling response time to pressure variations is immediate and hunting and oscillation is eliminated. (Mfd. by the W A Kates Co., and A Taube Co., 1363-T Anderson, Clawson, MI, USA). These devices have following drawbacks: The devices are very costly. The devices are very complex in its inside construction. Not easy to repair. Most importantly it requires 10-75 micro-meter filter to be installed at the up-stream of the device. It may be noted that the water in India does not meet out this requirement. The outlet pressure varies with the upstream pressure because it maintains a constant pressure drop across the metering orifice. The above mentioned, spring controlled flow-controlling devices are in used in USA/ Europe and
are not suitable for underdeveloped or developing countries like India, etc. It is because the water supplied for drinking purposes in these countries contains large amount of dissolved impurities. This water while passing through the filter (10-75 microns), shall choke the filter quite frequently. Also, with passage of time, the dissolved impurities present in the water, under no-flow conditions shall get deposited on the spring. This will affect the stiffness of the spring and resistance to flow in the region. This will affect the working of the device. On the other hand, the invented device does not require any filter (10 - 75 micrometer) or shut-off valve prior to the device. Also, the invented device does not require any spring.
Survey of the state of art in the area of present invention "pressure and flow-rate reducing device for fluid flow system" reveals that this device controls both pressure drop and flow-rate, whereas other existing valves controls either pressure or flow-rate.
BRIEF DESCRIPTION OF DRAWINGS:
Figure 1. Diagram of the pressure and flow- rate reducing device for fluid flow system showing the arrangement of orifice plates in the flow passage of a Pipe-Figure 2. Diagrams of orifice plates showing axisymmetric and non-axisymmetric shapes.
DETAILED DESCRIPTION WITH DRAWINGS:
Figure 1 and Figure 2 show cross-sectional details of pressure and flow-rate reducing device for fluid flow system. The fluid flows through a device fitted with one or more of concentric (axisymmetric)/ eccentric (non-axisymmetric) off-set orifice plates A, B, C, etc. of preset space, aperture shapes and sizes. The cross-sectional shape of the pipe and orifice apertures could be circular, square, rectangular, triangular, pentagon, hexagon, octagon (any polygon), parabolic, elliptical, etc. The present invention utilises the flow properties of fluid jet issuing from controlled aperture - geometrically and/or otherwise. The flow behaviour of such flows for standard concentric/ eccentric orifice geometries, non-standard configurations, off-set geometries, etc. have been used in the design of the pressure and flow-rate reducing valve for fluid flow system.
There is production of large number of smaller eddies. The size of these vortices causing eddies decides the required energy consumption from the main flow. The invented pressure and flow-rate reducing device for fluid flow system has following merits as compared to other devices:
Its internal geometry and working principle is unique. It has very simple configuration, easy to construct/ install and is very economical. It has no spring operated mechanism, unlike other foreign made valves. It requires no additional space and accessories like filter (10 to 75 micron), by-pass and shut-off valves etc. This makes it more acceptable in developed/underdeveloped countries. It does not use electro magnetic operated system, and therefore no external supply of energy is required. There is no moving part. Therefore, wear and tear is minimal. It is easy to clean, repair and maintain Maintenance cost is almost negligible. It gives controlled flow rate at nearly atmospheric pressure conditions at exit, irrespective of appreciable variations in the upstream pressure.
INDUSTRIAL APPLICATIONS:
The device has great potential and tremendous scope for industrial application in manufacturing sector, service sector and in public utilities. The device is useful for an industry such as refinery, chemical industry, thermal & hydro-electric power house, automobile industry, etc. where high pressure fluid flows through small or large network of pipes/conduits. It is seen that in industry as above where there are large networks of pipe wherein fluid flows under high pressure, the volume/mass flow-rate does not remain constant which results in big losses to industry both technically and financially. This device eliminates pressure pulses while maintaining constant flow-rate.
It can also be used in controlling water flow in pipes in tall buildings, water distribution in pipes in hilly areas, water distribution to buildings/houses from municipal water supply lines, networks, public utilities such as railway stations, bus-stands, airports or at any place where high pressure water out-flows. It is suitable for all types of industrial fluids (liquids and gases) including water and air at normal as well as high pressure and temperature conditions where ever simultaneous control of
fluid pressure and flow-rate is required. Apart from above, the device is suitable to work as safety valve in high pressure boilers, pressure cookers, industrial operations, etc. The device is suitable to get controlled flow-rate from high pressure gas cylinders such as LPG, CNG, etc. Some more explanation of the industrial applications are as follows:
1) Water Management in tall buildings: Residential/Commercial: In tall buildings, though energy losses are fairly appreciable but are still insufficient to reduce high pressures and flow rates to desired magnitudes at various outlet taps. The problem becomes more damaging at lower-level floors. These observations have been compared with experimentally set normal flow rate of 6-20 litres/min (« lxlO-4 - 3.33xl0-4 m3/s). Tall buildings have flow-rate approximately 85 litres/min or even more. At such high flow rates, it is very difficult to draw the desired quantity of water from an outlet tap, because water splashes all over with high velocity, wasting almost 80% of water coming out from the tap. At present in India, there is no flow controlling device in use to manage the water in tall buildings. The pre-calibrated device having series combination of concentric/eccentric orifice plates of various arrangements of orifice bores can be used in developed or under-developed countries to manage the water flow rate in tall buildings, because it has a fixed arrangement of orifice plates which gives normal flow rate of 6-20 litres/min (« lxlO-4- 3.33xl0-4m3/s) at about atmospheric pressure at the outlet. This has no movable arrangement controlled by spring mechanism as present in the foreign made very expensive valves. 2) Dams and Reservoirs: To produce electricity, we rotate the turbine by releasing the stored water at the back of the dam. The potential energy mgh equal to the difference of the height of water level h at up-stream and down-stream of the dam, gets converted into the kinetic energy 0.5 wv2 when the released water hits the floor at the down stream of the dam. Due to very high energy 0.5 m v2 of water (flow-rate), high amount of turbulence get generated which in turn eroded the floor at the down stream and can endanger to the stability of the dam. To protect the floor from this erosion, we creates artificial roughness in the floor, also we provides sheet-piles to ensure the safety of the dam which may be there due to erosion of soil, beneath of floor. By installing this
device (in a large number, as per the discharge requirements) in parallel in the floor at the hitting point of released water, the kinetic energy attained by the water may be get
diffused by passing the water through this device, because the flow rate at the out let of the device get substantially reduced and looses its kinetic energy. The installation of device shall not only reduce the cost of construction of the floor (thickness and roughness) but also shall eliminate the requirement of the sheet pile, which in turn will enhance the life of dam.
3) Incineration plants: a) Supply of combustion air: It is a well known fact that for combustion we require oxygen which is made available at the place of combustion by supplying air through artificial means such as pump, etc.. Generally in a furnace of an incineration/thermal plant the combustion of the fossil fuel like coal or civic waste take place, at the excess air mode. This air may enter into the furnace from below or from over the hearth. This air creates turbulence with in the fuel due to that the combustion of the fuel takes place and also the un-burnt fuel particles (suspended particulate matter, SPM) enter into the flue gases (i.e. the less efficiency to a thermal unit). These SPM enhance the load over the pollution controlling devices. If we install this device (in a large number, as per the flow requirements) in parallel between the pump and the furnace, the kinetic energy introduced by the pump in the air may be get diffused by passing the air through this device, because the flow rate at the out let of the device get substantially reduced and looses its kinetic energy. The installation of device shall not only reduce the availability of SPM in the flue gas and hence load over the pollution controlling devices but shall ensure the slow/steady availability of oxygen during combustion process i.e. the complete combustion of the fuel i.e. the high/maximum efficiency to a thermal unit. The complete combustion of the fuel shall also reduce the pollution of out side air due to the presence of CO (carbon monoxide) etc. in the flue gas. b) Recovery of heat from flue gas: In a thermal plant, the flue gas colleted at the end of the furnace is passed through a boiler to recover the heat from the flue gases. This heat is used for producing the steam, which rotates the turbine and produce electricity. Because the diameter of the pipes carrying the flue gas is much lesser than the diameter of the furnace the flue gas moves at high speed. Further the
diameter of the boiler tubes is much lesser than the diameter of the pipes carrying the flue gas, the flue gas moves at a very high speed through the boiler tubes. To achieve the required recovery of heat from the flue gas we increase the length of these tubes, which increases the size of the boiler and hence cost. If we install this device (in a large number, as per the flow requirements) in parallel between the flue gas pipe and the boiler, the kinetic energy introduced in the flue gas pipe may be get diffused by passing the flue gas through this device, because the flow rate at the out let of the device get substantially reduced and looses its kinetic energy. This flue gas when enter to the boiler shall gain some speed but shall definitely be lesser than earlier speed and hence shall require the lesser length of the boiler tubes for the same amount of heat recovery i.e. the small size of boiler and saving of cost, c) Recovery of the suspended particulate matters from the flue gas: In a thermal plant, the flue gas colleted at the end of the boiler is passed through pollution controlling devices to recover the suspended particulate matters from the flue gas. Here to remove the SPM from the flue gas entering at a very high velocity into the pollution controlling device, either we suddenly enlarge the size (diameter) of pollution controlling device or put obstruction between the path of the flue gas like jute bags, water spray etc. so that the particles may get settled due to the force of gravity. Because the flue gas enters at a very high velocity, the size of the pollution controlling device remains large to achieve the required efficiency. If we install this device (in a large number, as per the flow requirements) in parallel between the flue gas pipe and the pollution controlling device, the kinetic energy introduced in the boiler tubes/flue gas pipe may be get diffused by passing the flue gas through this device, because the flow rate at the out let of the device get substantially reduced and looses its kinetic energy. This flue gas when enter to pollution controlling device shall further loses its energy due to sudden enlargement of size, the recovery of SPM will require lesser size of the pollution controlling device i.e. lesser cost and better efficiency of SPM removal. 4) Distillation unit: In a distillation unit, the raw material is heated upto a desired temperature to recover the required product. For example in a petroleum refinery the crude petroleum is heated upto the desired temperature to recover kerosene
oil/diesel/petrol etc.. Due to heating of crude petroleum the vaporization of the crude takes place, which in turn is passed through a condensation unit to recover the fuel in liquid form. The condensation units are generally large in size. If we install this device (in a large number, as per the flow requirements) in parallel between the flue gas pipe and the condensation unit, the kinetic energy introduced in the flue gas pipe may be get diffused by passing the flue gas through this device, because the flow rate at the out let of the device get substantially reduced and looses its kinetic energy. This flue gas when enter to the condensation unit shall further looses its energy due to sudden enlargement of size, the recovery of fuel will require lesser size of the condensation unit i.e. lesser cost and better efficiency of fuel recovery.

WE CLAIM:
(1) The pressure and flow-rate reducing and controlling device for fluid flow system comprises single or plurality of concentric/eccentric orifice plates fitted or arranged in series inside the socket of the device and spacing of orifice plates and wire mesh is adjustable to suit pressure drop and flow-rate in any geometrical cross-section of pipe. Wherein, spacing in said consecutive plates lies in the range 0.8D to 3D, orifice aperture lies in the range 0.125D to 0.5D, and eccentricity of the orifice ranges from zero to maximum attainable value, where D is diameter of pipe.
(2) At the position of its installation in a fluid flow pipe, it creates required pressure drop and also controls simultaneously the flow-rate to required designed values.
(3) The orifice plates can be made from any material like glass, brass, stainless steel, acrylic sheet, viton, platinum silicon, EDPM, Buna-N, Teflon, Fluoro-polymer, etc. The material used should be non-corrosive, non-elastic, non-reactive with the flowing fluid.
(4) It is suitable for all types of fluids (liquids and gases) including water and air at normal as well as high pressure and temperature conditions.
(5) This device can be used where-ever simultaneous control of fluid pressure and flow-rate is required.
(6) This device is suitable in controlling water flow in pipes in tall buildings, water
distribution in pipes in hilly areas, water distribution to buildings/houses from
municipal water supply lines, networks, public utilities such as railway stations,
bus-stands, airports or at any place where high pressure water out-flows. This
device provides equal flow-rates at different elevations when pressures are
normally different from each other. This device also works in individual or
group housing for equal distribution of flow rate at various points within the
dwelling.
This device works equally well in any direction of fluid flow in vertical, horizontal, inclined and zigzag/curvilinear pipes or conduits.
(7) This device is suitable to get controlled flow-rate from high pressure gas cylinders such as LPG, CNG, etc.
(8) This device is suitable to work as safety valve in high pressure boilers, pressure cookers, industrial operations, etc.
(9) The device shall be useful in industrial applications such as refinery, chemical industry, thermal & hydro-electric power house, automobile industry, etc. where high pressure fluid flows through pipes/conduits in small or large network.