pumps

2017 ALEXANDRIA UNIVERSITY, FACULTY OF ENGINEERING, Mechanical Engineering Department, Hydraulic Machines and Fluid Mechanics Branch. [THE PUMPS,THE HEART OF THE CIRCUIT] In this report we are going to introduce a description about some different types of pumps, the principle of working and the main components. In addition that a unique pump will be presented and discussed briefly. Dr. Sadek Z. Kassab NAME SEAT NO ‫احمد السيد محمد حبشى‬ ‫احمد بخيت محمد بخيت‬ ‫احمد جمال على حمودة‬ ‫احمد حافظ محمد حافظ‬ ‫محمد احمد جابر عبدالحميد‬ 10 31 31 18 266 1 Table of Contents i. Introduction ............................................................................. 5 ii. Centrifugal Pumps ................................................................. 7 2-1 How do CENTRIFUGAL PUMPS work? .................................. 8 2-2 How many Types are there? ................................................ 9 2-3 How they are made and what are the main components? 12 iii. Piston Pumps ....................................................................... 14 3-1 Introduction....................................................................... 14 3-2 How do PISTON PUMPS work? .......................................... 16 3-3 How many Types are there? .............................................. 17 3-4 How they are made and what are the main components? 21 3-5 Advantages and Disadvantages of Reciprocating Pumps ... 22 iv. Diaphragm Pump ................................................................. 23 4-1 How do DIPHRAGM PUMPS work? .................................... 24 4-2 How many Types are there? .............................................. 25 4-3 How they are made and what are the main components? 27 4-4 What THEY'RE great for? ................................................... 28 v. Gear pumps ......................................................................... 29 5-1 How do GEAR PUMPS work? ............................................. 29 5-2 How many Types are there? .............................................. 30 5-3 How they are made and what are the main components? 31 5-4 Gear pump basic calculations ............................................ 32 2 5-5 Sample of gear pump selection from bucher hydraulics catalogue ................................................................................. 32 5-6 What THEY'RE great for? ................................................... 34 vi. Vane pumps......................................................................... 35 6-1 How do VANE PUMPS work? ............................................. 35 6-2 How they are made and what are the main components? 36 6-3 What THEY'RE great for? ................................................... 37 vii. Lobe Pumps ......................................................................... 38 7-1 How do LOBE PUMPS work? .............................................. 39 7-2 How many Types are there? .............................................. 40 7-3 How they are made and what are the main components? 40 7-4 What they’ e g eat Fo ? .................................................... 41 viii. THE LUB DUB PUMP ......................................................... 42 8-1 Introduction....................................................................... 42 8-2 The heart of the circuit ...................................................... 44 8-3 The prime mover ............................................................... 47 8-4 The valves .......................................................................... 49 8-5 The piping system (not rigid system) ................................. 51 8-6 The reservoir ..................................................................... 53 8-7 The actuators ..................................................................... 53 8-8 Other hydraulic components ............................................. 53 8-9 Simple Hydro-mechanical model of the human circulatory system ..................................................................................... 55 ix. TABLE OF FIGURES ............................................................... 56 3 x. References and External links ................................................ 58 4 i. Introduction The pump is one of the main components of any hydraulic circuit, Pump is a machine or mechanic equipment which is required to lift liquid from low level to high level or to increase liquid pressure to do a specified purpose and also as a debit booster in a piping network system, pump converts mechanical energy of motor into fluid flow energy. Energy which is received by fluid will be used to lift pressure and to bridge over resistances which are exists in the line that passed. Pump can be classified into two categories, 1. Positive displacement pumps (PDP) 2. Dynamic pumps Fig (1-1) 5 In PDP, energy is periodically added by application of force to one or more movable boundaries of any desired number of enclosed, fluid-containing volumes, resulting in direct increase in pressure up to the value required to moves the fluid through vales or ports into the discharge line. PDP is used mainly in hydraulic circuits where high pressure is required. PDP divided into two: 1) Reciprocating pump (piston, plunger and diaphragm) 2) Rotary pump (gear, lobe, vane and screw) Dynamic pump is consist of one or more impeller which is completed by blades, which is installed on moving shafts and receive energy from pump motor and it is covered by a casing. Energize fluid enters impeller axially, and then fluid leaves impeller with relative high speed and collected in volute or diffuser, after fluid collected in volute or diffuser, the conversion of velocity head to pressure head occur, which is followed by velocity decreasing. After this conversion process has done and then fluid out of pump through discharge valve. Dynamic pump can be divided into some types: 1) Centrifugal pump (axial, mixed and radial) 2) Special effect pump (jet and air lift pump) 6 ii. Centrifugal Pumps Centrifugal (dynamic) pumps are the most common dynamic pump used in industry. Centrifugal pump consists of two main parts:  A rotating part that includes a shaft and impeller.  A stationary part made up of a casing, stuffing box and bearings.  It is commonly driven by an electric motor.  Dynamic pumps are best suited to high flows at low pressures or heads. Now we are going to discuss the CENTRIFUGAL PUMPS and our objectives will be trying to answer the following:1) How do they work? 2) How many types are there? 3) How they are made and what are the main components? Fig (2-1) 7 Fig (2-2) 2-1 How do CENTRIFUGAL PUMPS work? 1) As the pump shaft rotates liquid is drawn into the opening in the center of the impeller (referred to as the suction eye). As shown in Fig (2-3) and Fig(2-4) 2) This is caused by the force created by the weight of the fluid itself (suction head) or by the pressure differential caused by a partial vacuum created by the movement of the impeller (suction lift). 3) Once the liquid is in the impeller it has to follow the path described by the blades and is flung outwards with centrifugal force, thus gaining velocity. Impellors turn at 1725 or 3600 rpm. 4) It then enters the collector (volute or diffuser) a casing that surrounds the impeller and slows the liquid to a usable velocity. 5) The kinetic energy or velocity energy is converted to pressure. Fig (2-3) Fig (2-4) 8 2-2 How many Types are there?  There are many factors that can affect the type of the dynamic pump. But the most common factor is the style of the impeller. “As shown in the fig 5 “ Dynamic Pump Impeller styles Fig (2-5) 9 a. Radial Flow: The radial flow impeller discharges the fluid radially at 90° to the shaft axis.  Usage: Major pressure need to be overcome. (Differential head, pressure drops, high specific weight or high viscosity) b. Axial Flow: The axial flow impeller discharges fluid along the shaft axis. For this reason an axial flow pump is by definition not "centrifugal" in its pumping action.  Usage: Free run out and no significant pressure losses.(decanting a huge amount of liquid) c. Mixed Flow: The mixed flow impeller discharges fluid in a conical direction using a combined radial and axial pumping action Fig(2-6) 10 Table 1 comparison between radial flow impeller and axial flow impeller Radial-flow impeller = L Axial-flow impeller= R Usage: Major pressure need to be overcome. (differential head, pressure drops, high specific weight or high viscosity) Usage: Free run out and no significant pressure losses.(decanting a huge amount of liquid) High delivery head High delivery rate          heavy liquids (density > 1,0 kg/dm3) viscous liquids long discharge pipework differential head to overcome pressure drops due to valves, fittings, flow meter filling small canisters low power consumption at a small flow rate (0 to 55 l/min) small decrease of the flow rate at increasing operating pressure insensitive to changes in operating conditions 11          light liquids (density < 1,0 kg/dm3) thin-bodied liquids short discharge pipework low differential head to overcome low pressure drops emptying big containers, pumping high flow rates low power consumption at a larger flow rate (55 o 200 l/min) noticeable decrease of the flow rate at increasing operating pressure sensitive to changes in operating conditions 2-3 How they are made and what are the main components? Fig (2-7) 1. Impeller: Main rotating part that provides centrifugal acceleration to the fluid  Number of impellers = number of pump stages  Impeller classification: direction of flow, suction type and shape/mechanical o st u tio Fig (2-8) Fig (2-8) 12 2. Shaft: Transfers torque from motor to impeller during pump start up and operation 3. Casings: - Fig (2-9)  Functions • E lose i pelle as p essu e essel • Support and bearing for shaft and impeller Volute case Impellers inside casings Balances hydraulic pressure on pump shaft Circular casing Vanes surrounds impeller Used for multi-stage pumps 13 Fig (2-9) iii. Piston Pumps 3-1 Introduction The positive displacement principle applies whether the pump is a          rotary lobe pump progressing cavity pump "Fig (3-1)" rotary gear pump piston pump diaphragm pump screw pump gear pump vane pump regenerative (peripheral) pump "Fig(3-2)"  peristaltic "Fig(3-3)" Fig (3-1) A Positive Displacement Pump, unlike a Centrifugal or Rotodynamic Pump, will produce the same flow at a given speed (RPM) no matter the discharge pressure. The Positive Displacement Pumps is a "constant flow machine" 14 Fig (3-2) Fig (3-3) 15 3-2 How do PISTON PUMPS work? A piston pump is the type of reciprocating pump that moves & pressurizes fluid by using one or more reciprocating pistons ; it is driven by an electric motor through a crankshaft & connecting rod Piston pumps can handle the following ranges:  Flow rates between 5 and 700 gpm  Total head (pressure) between 50 and 5000 psi  Horsepower between 1 and 500 hp How do they work?  A Piston Pump is very similar in construction to a Reciprocating Internal Combustion Engine. Like most positive displacement pumps, they operate by using the force of the pumping mechanism to expand & contract an interval movable volume of liquid. Piston pump can have more than one piston & set of check valves. A duplex pump has 2 pistons & 2 sets of check valves, A triplex has 3 and so on.  The basic pumping action is obtained by reciprocation of a piston in a cylinder. The cylinder has two valves. And they allow for inwards and outwards movement of the liquid respectively. These valves are situated in inlet and outlet manifold respectively. The piston is connected to a crankshaft through a connecting rod. Fig (3-4) 16 3-3 How many Types are there? Swash plate The rotating group consists of : Pressure plate, Piston Barrel, Pistons, Piston Shoes, Swash plate and Drive Shaft. "Fig (3-5)" The pistons travel inside the barrel bores sucking and pumping oil while the rotating group rotates. The Control, also called compensator is generally an external element attached to the case. There are many variations of a compensator, some of them very complex, but we can say that in general it controls the maximum pressure, the flow that the pump delivers and in other cases the maximum torque and even power. "Fig (3-6) & Fig (3-7)"   Fig (3-6) Fig (3-5) 17 Fig (3-7) Bent Axis Pump  In this pump, the pistons are at an angle to the drive shaft and Thrust Plate.  The piston block shaft is connected to the drive shaft by a universal joint.  The drive shaft, thrust plate, piston block shaft, and piston block all revolve.  The connecting rods are attached to the thrust plate and revolve with it, unlike the swash plate pump where the piston rods slide past a stationary swash plate.  As the pump revolves, half the pistons suck in fluid as they pass over the intake port. The other pistons discharge their fluid through the outlet port. 18 Fig (3-8) Wobble Plate Piston Pump  This pump has pistons in a stationary block, and a rotating wobble plate.  There might be 4, 5, or more pistons (usually an odd number are used)  Each piston has a valve within it and another valve behind it.  The pistons are pushed against the wobble plate with large springs.  This type of pump can develop incredible pressure -- 10,000 PSI or more.  It is commonly used for low-volume applications. Handoperated wobble pumps were used as emergency fuel pumps on some early aircraft. Fig (3-9) 19 Radial Piston Pump  Radial Piston Pumps can produce a very smooth flow under extreme pressure.  Flow rate changes when the shaft holding the rotating pistons is moved W.R.T the casing  An odd number of pistons is always used to smooth the hydraulic balance  These pumps revolve at speeds up to about 1200 RPM Fig (3-10) 20 3-4 How they are made and what are the main components?  Crank: Crank is a circular disk attached to the motor and used to transfer the rotation motion of the motor to the piston.  Connecting rod: Connecting rod is the long solid rod. It provides connection between crank and the piston. It also converts the rotation motion of crank into the linear motion of the piston.  Piston: Piston is the solid cylinder like part of the pump which moves linearly in the hollow cylinder of the pump. It motion is main reason behind suction and deliverance of the liquid.  Cylinder: It is a hollow cylinder in which piston moves. Suction and deliverance take place within it. Suction and delivery pipe and valves are attached to its one end piston come and go back from other end.  Suction pipe: Pipe which take liquid from the source and provide it to the cylinder of the pump is called suction pump.  Suction valve: It is one way valve place between suction pipe and cylinder of the pump. It is open when suction takes place and close when delivery of the water is taking.  Delivery pipe: Pipe which take water from the cylinder of the pump and provide it to the tank is called delivery pipe.  Delivery valve: It is one away vale and placed at the point of attachment of delivery pipe with cylinder. It is open when delivery of water is taking place and closed when suction of water in taking place.  Strainer: It is a filter like parts provided at the end of suction pipe. Its main function is to stop is solid particles from entering into the pipe.  Air vessel: Installed at the suction and delivery pipe and its main function is to give a steady flow by reducing the frictional head. 21 3-5 Advantages and Disadvantages of Reciprocating Pumps Advantages of reciprocating pump      High efficiency No priming needed Can deliver water at high pressure Can work in wide pressure range Continuous rate of discharge Disadvantages of reciprocating pump      More parts mean high initial cost High maintenance cost No uniform torque Low discharging capacity Pulsating flow Fig (3-11) 22 iv. Diaphragm Pump Fig (4-1) Diaphragm Pumps have a diaphragm as the reciprocating part. The reciprocation of this diaphragm produces the pumping action of the diaphragm pump. The diaphragm can be actuated by liquid or air. Accordingly pumps are called as hydraulically operated or air operated diaphragm pumps. Next, as followed in the previous types the working principle, the main types, the main components and where we could find this type of pumps? Will be presented. 23 4-1 How do DIPHRAGM PUMPS work? By the action of the actuators the diaphragm bulges in and out of the liquid chamber. When the diaphragm bulges out of the liquid chamber the volume of the chamber increases and pressure inside the chamber decreases, this opens the inlet valve and liquid is taken inside the chamber. When the diaphragm bulges in the chamber the volume of the chamber decreases and the pressure increases which opens the outlet valve and the liquid is pumped out of the chamber. The diaphragm does not have any frictional motion with the chamber, thus, there is no need of any seal or liner. Fig (4-2) Fig (4-3) 24 4-2 How many Types are there? 1. Hydraulically Operated Diaphragm Pump The diaphragm is reciprocated by the action of hydraulic fluid and the fluid itself is pumped by a reciprocating piston. Thus, one piston pump is making the other diaphragm pump work. The diaphragm has driving hydraulic fluid one side and the liquid to be pumped on the other side. The piston pumps the driving fluid which moves the diaphragm and in turn pumps the liquid on the other side. This arrangement avoids any contact between the pumping element and the liquid pumped. This avoids leakage and makes the pump suitable for handling expensive, explosive or toxic liquids. Fig (4-4) 25 2. Air Operated Diaphragm Pumps The Air Operated Diaphragm Pumps have two chambers, each divided into two parts by flexible diaphragms. The liquid side of both the chambers has inlet and outlet non return type valves. The centers of the two diaphragms are interconnected with a rigid rod. There is a supply of pressurized air which is controlled by a valve system. At one time it allows air to enter one of the air chamber and exhaust from the other chamber. Fig (4-5) 26 4-3 How they are made and what are the main components? Fig (4-6) 27 4-4 What THEY'RE great for? These pumps are an excellent choice for applications found in a variety of industries, such as food, chemical, and general industry. Their unique design allows them to transfer highly abrasive or viscous products, semi-solid, and shear sensitive materials. They're best known for ease of maintenance and replacement, self-priming ability, seal-less design, and their ability to "run dry" without causing damage to the pump. What else makes the AODD pump so versatile? They're manufactured in a variety of pump materials, including cast iron, stainless steel, special alloys, and various diaphragm and valve elastomers making them ideal for just about any market. Best application for this pump     Chemical or hazardous liquid transfer. Abrasive or viscous product transfer. Portable spill clean-up applications. Explosion-proof environments if properly grounded. Disadvantages AODD pumps do generate a pulsating flow that could cause "water hammer" if proper pulsation dampening devices aren't used. Water hammer is a pressure surge, or wave, created when a fluid in motion is forced to stop or suddenly change direction causing significant damage to the pump and/or process piping. . 28 v. Gear pumps The external gear pump is a positive displacement (PD) type of pump generally used for the transfer and metering of liquids. The pump is so named because it has two gears that are side- by- side or external by each. 5-1 How do GEAR PUMPS work? Fig (5-1) The working principle of the external gear pump is illustrated in Fig (5-1). A drive gear (that is driven by a motor) rotates an idler gear in the opposite direction. When the gears rotate the liquid which is trapped in the gear teeth spaces between the housing bore and the outside of the gears is transferred from the inlet side to the outlet side. 29 5-2 How many Types are there? Gear pumps divided into  External gear pump  Internal gear pump Fig (5-2) Fig (5-3) 30 5-3 How they are made and what are the main components? The basic construction is      Idler gear Idler shaft Drive gear Drive shaft Housing All components all shown in Fig (5-1) Fig (5-4) 31 5-4 Gear pump basic calculations 1. Volumetric displacement vd, vd=0.25pi(do^2-di^2)L where: Do: outside diameter Di: inside diameter L: width of teeth 2. Theoretical flow rate Qt =vd*N Where N is the speed in rpm 3. Volumetric efficiency = Qa/Qt where Qa is the actual flow 5-5 Sample of gear pump selection from bucher hydraulics catalogue 32 Table (5-1) gear pump selection from bucher 33 5-6 What THEY'RE great for? Gear pump applications     Various fuel oils and lube oils Chemical additive and polymer metering Chemical mixing and blending (double pump) Industrial and mobile hydraulic applications (log splitters, lifts, etc.)  Acids and caustic (stainless steel or composite construction)  Low volume transfer or application Gear pump advantages  Cheap compared to other types  Simple design  Self-priming Gear pump disadvantages  Low volumetric efficiency due to wear  High maintenance cost.  Not used in high suction lifts 34 vi. Vane pumps Fig (6-1) 6-1 How do VANE PUMPS work?  A slotted rotor is eccentrically supported in a cycloidal cam.  The rotor is located close to the wall of the cam so a crescent-shaped cavity is formed.  The rotor is sealed into the cam by two side plates.  Vanes or blades fit within the slots of the impeller.  As the rotor rotates and fluid enters the pump, centrifugal force, hydraulic pressure, and/or pushrods push the vanes to the walls of the housing.  The tight seal among the vanes, rotor, cam, and side plate is the key to the good suction characteristics common to the vane pumping principle. 35  The housing and cam force fluid into the pumping chamber through holes in the cam.  Fluid enters the pockets created by the vanes, rotor, cam, and side plate.  As the rotor continues around, the vanes sweep the fluid to the opposite side of the crescent where it is squeezed through discharge holes of the cam as the vane approaches the point of the crescent (small red arrow on the side of the pump). Fluid then exits the discharge port. 6-2 How they are made and what are the main components? Fig (6-2) 36 6-3 What THEY'RE great for?          Aerosol and Propellants Aviation Service - Fuel Transfer, Deicing Auto Industry - Fuels, Lubes, Refrigeration Coolants Bulk Transfer of LPG and NH3 LPG Cylinder Filling Alcohols Refrigeration Solvents Aqueous solutions Advantages       Handles thin liquids at relatively higher pressures Compensates for wear through vane extensions Sometimes preferred for solvents, LPG Can run dry for short periods Can have one seal or stuffing box Develops good vacuum Disadvantages     Can have two stuffing boxes Complex housing and many parts Not suitable for high pressures Not suitable for high viscosity and abrasives 37 vii. Lobe Pumps Fig (7-1)  Rotary lobe pumps can be found in a wide variety of industries, from sanitary markets like food and beverage, to less than sanitary markets like wastewater treatment. Their popularity stems from a number of attractive properties like high efficiency, reliability, solids handling ability and sanitary qualities.  Rotary lobe pumps are similar to the external gear pump. They operate in the same fashion, except that the rotary lobe uses "lobes" instead of gears to move fluid through the pump. 38 7-1 How do LOBE PUMPS work? Fig (7-2) Unlike external gear pumps, the lobes do not make contact. Lobe contact is prevented by external timing gears located in the gearbox. Pump shaft support bearings are located in the gearbox, and since the bearings are out of the pumped liquid, pressure is limited by bearing location and shaft deflection.  As the lobes come out of mesh, they create expanding volume on the inlet side of the pump. Liquid flows into the cavity and is trapped by the lobes as they rotate.  Liquid travels around the interior of the casing in the pockets between the lobes and the casing -- it does not pass between the lobes.  Finally, the meshing of the lobes forces liquid through the outlet port under pressure. 39 7-2 How many Types are there? These types are: single, bi-wing, tri-lobe, and multi-lobe. Fig (7-3) 7-3 How they are made and what are the main components? Fig (7-4) 40 7-4 What they’re great For? Rotary lobe pumps are very popular in food applications because of their ability to carefully handle low shear fluids and solids, without damaging the product. Because the lobes do not touch, large particles are handled more easily than with other types of positive displacement pumps. It is also good for abrasive applications for the same reason. What they’re not great for Low viscosity fluids are difficult for rotary lobe pumps. Clearances are not tight enough to efficiently handle these types of fluids. Best applications for this pump: Soaps -Paints and dyes-Wide variety of food applications Polymers-Paper coatings-Rubber and adhesives. Adventages Pass medium solids No metal-to-metal contact Long term dry run (with lubrication to seals) Non-pulsating discharge Superior CIP/SIP capabilities Disadventages Requires timing gears Requires two seals Reduced lift with thin liquids Table (7-1) advantage and disadvantage of lobe pumps 41 viii. THE LUB DUB PUMP 8-1 Introduction It is not a strange or unbelievable thing that the most used pump ever is not a man-made pump and it is the absolute truth. Lub dub lub dub lub dub is the sound of that pump and from here the name is chosen we are going to talk about the human heart and the corresponding circulatory circuit. Fig (8-1) 42 The main components of the hydraulic circuit Any hydraulic circuit consists of main six components.       The pump (the heart of the circuit) The prime mover (the energy adding unit) The valves (the controllers) The piping system (the convey unit) The reservoir (the oil supply unit) The actuators (the muscles –energy dissipating -) Besides these components there are     The filters The drains The Sensors The accumulators Fig (8-2) 43 8-2 The heart of the circuit When observing a cross-section of the human heart, you will recognize four chambers- the right atrium, the right ventricle, the left atrium and the left ventricle- and four valves that make up the organ. The human heart is like a positive displacement pump and could be modulated as the diaphragm pump or the piston pump, the left and right atria work as our hydraulic pump, contracting simultaneously to pump blood into the right and left vesicles. The vesicles then also contract, pumping the blood back out of the heart. Our heart beats approximately between 70 to 90 times a minute. Fig (8-3) 44 In the fact it is not only one pump they are two pumps- the right ventricle and the left ventricle, each pump deliver a different head but in series configuration, one for pulmonary system and the other for the systemic circulatory system. Fig (8-4) The pumping chambers are collapsible and usually pumps about 70 ml /stroke. The right ventricle squeezes down and raises the pressure of the blood to about 25 mmHg, after passing through the lungs, the blood pressure is back down to about 5 mmHg (a reduction of 20 mmHg). It goes into the left ventricle a second squeeze causes the pressure to rise back up to about 120mmHg. Each millimeter of mercury = 0.133 kilopascals 45 Why two pumping unit? Fig (8-5) It’s a tually a g eat uestio , si e at first glance it seems like it would be more efficient to just allow the blood to go out to the body instead of taking a return trip to the heart. Let’s say that the right ventricle raised the pressure up to 140mmHg, then you may be able to have the blood pressure drop 20mmHg and still be at 120mmHg.  If exposed to those high pressures, fluid would get pushed right out of the capillaries and into the lungs (some capillaries would actually break)  At high pressures, blood would move past the lungs so quickly that O2 wouldn't have time to diffuse into the blood. That’s hy the hu a ody eeds t o pu ps, high p essu e to allow the blood to circulate around the body, and low pressure for optimal gas exchange in the lungs without broken capillaries! 46 8-3 The prime mover In conventional circuits the pumps should be powered by external mover called (prime mover) which could be electric motor, diesel engine, gas turbine or even steam turbine, I can't imagine a steam turbine inside my body. The heart does not have an external prime mover but it could be considered as a pump and its prime mover in one unit –a double function-. The heart receives its signal from brain as electric signal delivered to the sinoatrial node then to the trioventricular node which deliver it to the heart muscles. Fig (8-6) The heart wall is made up of three layers: the inner endocardium, middle myocardiumand outer epicardium. These are surrounded the pericardium. 47 The middle layer of the heart wall is the mover which contains the cardiac muscle. Another amazing fact that the left side of the heart is thicker and its muscles are stronger because it pumps blood at high pressure (120mmHg) nearly 5 times the right side (20 mmHg). Fig (8-7) 48 8-4 The valves Directional control valve There are four valves in certain locations of the heart –the aortic valve, the pulmonary valve, the mitral valve and the Tricuspid valve –. Valves make sure that the blood goes in one direction (Directional control valve). If the blood try's into the opposite the direction, the valves close, not allowing the blood to go in the opposite direction. Fig (8-8) We should notice that  The tricuspid valve and the mitral valve - on the suction lines of LP & HP pumps – are linked to the heart muscles to ensure complete enclosure during pumping action.  The suction valves are larger than the delivery valve (d suction > d delivery) reducing pressure drop at the suction to avoid cavitation. 49  The aortic valve and the pulmonary valve –on the delivery lines of LP & HP pumps – have three cusps and are free to move why? That is from the fact that the delivery valve of the positive displacement pump must be opened easily to avoid pressure accumulation and pump failure Flow control valves Another unexpected type of valves can be modeled in the system is the flow control valves Fig (8-9) The Capillary beds regulate the flow of blood through themselves. This allows the different organs to maintain continuous blood flow despite the change in the blood pressure. This is achieved by smooth muscle response in the capillary wall. When blood pressure in the arteries that feed the capillary network increases, the walls of the capillaries contracts to counteract high blood pressure and prevent increasing blood flow. In the lungs, a reversed mechanism is used to meet the needs of increased blood flow during exercises. 50 8-5 The piping system (not rigid system) The main piping is consists of the arteries, the veins and the capillaries. Being carry high pressure blood the arteries are thicker than the veins and have elastic layer that helps in pressure change and pumping action. Fig (8-10) Fig (8-11) 51 Pressure distribution in piping system Fig (8-12) Pressure distribution in the heart Fig (8-13) 52 8-6 The reservoir The blood is pumped in a continuous closed loop, so there is no significant origin could be considered as a reservoir. And that doesn't contract with the previous talk –the upper left and right chambers are instantaneous tanks for the pumps and the piping system is the blood vessel – 8-7 The actuators Despite the blood works as a hydraulic fluid for the positive displacement pump (the heart); its function is not to move an actuator (hydraulic motor or cylinder), it works as a convey fluid like one used in grains transport, it convey proteins and O2 to the entire human cells 8-8 Other hydraulic components There are other components are essential for the efficient work of the hydraulic circuits.  The filters, contaminated fluid is not desirable because it reduces the life of the pump and could block the piping and valves which need much more pumping power to avoid these losses. 53 1. The lungs are the main filter in the human body; it oxygenates the blood and removes CO2 through the alveoli. 2. The kidneys, all of the blood in your body passes through them several times a day. Blood comes into the kidney, waste gets removed, and salt, water, and minerals are adjusted, if needed. The filtered blood goes back into the body. Waste gets turned into urine.  The drains, to get rid of all the waste. The bladder is the drain for the urine. The Spleen and the liver are the red blood cells drains.  The make-up source, getting rid of some dead blood needs another fresh blood to take its place that is done by the red bone marrow. Till now we have discussed the lub dub pump and the circulatory system and its main components in the hydraulic circuit point of view. Fig (8-14) 54 8-9 Simple Hydro-mechanical model of the human circulatory system      Fig (8-15) CSV: average compliance of body system veins. CPV : average compliance of pulmonary veins; CSA :average compliance of body system arteries; CPA : average compliance of pulmonary arteries; RSYS: flow resistance through internal organs and body system capillaries;  RPUL: reduced flow resistance through pulmonary vessels The System consists of 2 piston pumps, 4 directional control valves, 2 flow control valves and 4 energy storage units due to piping elasticity. The harder question is determining how it began beating. 55 ix. TABLE OF FIGURES Fig (1-1) pumps classifications ....................................................... 5 Fig (2-1) centrigugal pump components ........................................ 7 Fig (2-2) installed centrifugal pump ............................................... 7 Fig (2-3) centrifugal pump flow direction ...................................... 8 Fig (2-4) centrifugal pump flow direction ...................................... 8 Fig (2-5) Dynamic Pump Impeller styles......................................... 9 Fig(2-6) pump curves ................................................................... 10 Fig (2-7) centrigugal pump main components ............................. 12 Fig (2-8) impeller types ................................................................ 12 Fig (2-9) cross section in centrifugal pump .................................. 13 Fig (3-1) progressing cavity pump ................................................ 14 Fig (3-2) ege e ati e pe iphe al pu p……………………………………15 Fig (3-3) peristaltic pump ............................................................. 15 Fig (3-4) piston pump strokes ...................................................... 16 Fig (3-5) swash plate .................................................................... 17 Fig (3-6) compenator ................................................................... 17 Fig (3-7) compensated vs not cmpensated pump ........................ 18 Fig (3-8) bent axis pump .............................................................. 19 Fig (3-9) Wobble Plate Piston Pump ............................................ 19 Fig (3-10) Radial Piston Pump ...................................................... 20 Fig (3-11) performance curve ...................................................... 22 Fig (4-1) Diaphragm Pump ........................................................... 23 Fig (4-2) Diaphragm Pump suction .............................................. 24 Fig (4-3) Diaphragm Pump delivery ............................................. 24 Fig (4-4) Hydraulically Operated Diaphragm Pump ..................... 25 56 Fig (4-5) Air Operated Diaphragm Pumps .................................... 26 Fig (4-6) main Components of Diaphragm Pump ......................... 27 Fig (5-1) gear pump ..................................................................... 29 Fig (5-2) external gear pump ....................................................... 30 Fig (5-3) internal gear pump ........................................................ 30 Fig (5-4) main Components of gear Pump ................................... 31 Fig (6-1) Vane pump .................................................................... 35 Fig (6-2) main Components of vane Pump................................... 36 Fig (7-1) Lobe Pump ..................................................................... 38 Fig (7-2) Lobe Pumps operation................................................... 39 Fig (7-3) types lobe pump ............................................................ 40 Fig (7-4) main Components of lobe Pump ................................... 40 Fig (8-1) heart muscles contract and relax................................... 42 Fig (8-2) The main components of the hydraulic circuit .............. 43 Fig (8-3) heart components ......................................................... 44 Fig (8-4) heart as a double pump ................................................. 45 Fig (8-5) one pump vs two pumps ............................................... 46 Fig (8-6) heart control unit .......................................................... 47 Fig (8-7) heart muscles and layers ............................................... 48 Fig (8-8) heart valves ................................................................... 49 Fig (8-9) capillaries as flow control valves ................................... 50 Fig (8-10) piping system in human body ...................................... 51 Fig (8-11) veins vs arteries ........................................................... 51 Fig (8-12) Pressure distribution in piping system ......................... 52 Fig (8-13) Pressure distribution in the heart ................................ 52 Fig (8-14) circulatory system........................................................ 54 Fig (8-15) Simple Hydro-mechanical model of the human circulatory system ........................................................... 55 57 x. References and External links [1] Mathematical Modeling of the Hydro-Mechanical Fluid Flow System on the Basis of the Human Circulatory Syste, Wiktor Parandyk, Donat Lewandowski, Jan Awrejcewicz. [2] Human circulatory system in terms of a closed loop hydraulic structure, Wiktor Parandyk, Donat Lewandowski, Jan Awrejcewicz. [3] Engineering Modeling of Human Cardiovascular System, Hassanain Ali Lafta Mossa. [4] Fluid mechanics and hydraulic machines-by R K BANSAL . [5] Engineering_Design_Guideline__Pump_Rev3.pdf [6] Lobanoff, V.S. and Ross, R.R., 2013. Centrifugal pumps: design and application. Elsevier. [7] Bloch, H.P. and Budris, A.R., 2004. Pump user's handbook: life extension. The Fairmont Press, Inc... [8] Sahdev, M., 2005. Centrifugal Pumps: Basic concepts of operation, ai te a e a d trou leshooti g, Part I. Режим доступу–http://www. cheresources. Com. [9] Streeter, Victor L., Fluid Mechanics, 5th Edition, McGraw-Hill, New York, ISBN 07-062191-9. [10] Esposito, Anthony, Fluid Power with Applications, Prentice-Hall, Inc., New Jersey, ISBN0-13-322701-4. [11] Positive Displacement Pumps (Part One) Reciprocating Pumps [12] Engineering gear pumps basics .pdf [13] Bucher hydraulic gear pumps manual 58 [14] Slideshare.net [15] Hidraulicapractica.com [16] Wikipedia.net [17] www.khanacademy.org/science/health-and-medicine/circulatorysystem/circulatory-system-introduction [18] http://www.engineeringtoolbox.com/pumps-t_34.html pumps. [19] https://www.michael-smith engineers.co.uk/mse/uploads/resources/useful-info/PumpingPrinciples/Vane-Pump-Principles.pdf [20] http://www.pumpschool.com/principles/external.asp [21] https://www.youtube.com/watch?time_continue=61&v=8Nh0CUzMhI [22] https://www.youtube.com/watch?v=wJmYEh7jBqI [23] https://www.youtube.com/watch?v=tGXu27UTIY4 [24] https://www.youtube.com/watch?v=xRkhItewctw 59