Hydraulic design of sewers and storm water drains lecture 8. The manner in which fluid flows through the pump is determined by the design of the pump casing and the impeller. In many fluid power applications, energy losses due to flow in valves and fittings exceed those due to flow in pipes. Tosolveaproblemusingdimensionalanalysis,writedownallrelevantvariables1,theircorresponding.
Excel spreadsheet formulas can be conveniently used to make calculation for differential pressure flow meters, like an orifice flow meter, a venturi meter, or a flow nozzle meter. Writing the darcyweisbach dw equation for flow through these pipes, we find. We remark that this is one of the main features of the current lectures that is not present in usual treatments. Flow through pipes study notes for civil engineering.
The venturimeter is used to measure the rate of flow of a fluid flowing through the pipes. I want to calculate the back pressure of psv or bdv. It is evident that the quantity of water will equal a column whose. Flow between parallel plates, flow through long tubes, flow through inclined tubes.
There are many types of losses of head for flowing liquids such as friction, inlet and outlet losses. The more circuitous is the path, the greater are the losses. Reynolds number, darcyweisbach equation, use of moody reynolds number, darcyweisbach equation, use of moody diagram, minor lossessudden expansion, sudden contraction and losses in pipe fittings. From reynolds experiments on pipe flows of various diameters, it was observed that there is a critical reynolds number below this value, pipe flow is laminar. The derivation of the hagenpoiseuille equation for laminar flow in straight, circular pipes is based on the following two assumptions. A pipe fitting is used in plumbing system to join multiple pipes of same size or different sizes, to regulate the flow or to measure the flow. Part 1 basic principles of fluid mechanics and physical. Figure 5 shows the schematic layout of the pipe network to be used in the present study. In laying the pipes through the distribution area, the following configuration can be distinguished.
The islamic university of gaza environmental engineering department networks design and pumping stations. In a radial flow pump, the liquid enters at the center of the impeller and is directed out. Initially when the piston moves down, air is sucked in through the inlet valve. Learn for free, pay a small fee for exam and get a certificate. Flow between parallel plates, flow through long pipes, flow through inclined pipes. To find the coefficient of discharge for venturi meter.
Pressure drop in tail pipe posted in relief devices forum. Venturimeter principle, construction and working with. Viscosity the viscosity of a fluid is a measure of its resistance to a tangential force. However, field inspections of completed projects and the literature. Fundamentals of fluid mechanicsfluid mechanics chapter 8. The tech taylor valve operates on a simple principle where a rubber coated ball is allowed to move freely within the valve body. Browse the application gallery and download tutorial models with instructions and view example apps. These deaign notes primarily coyer simple gravity flow water systems. Nptel iit kharagpur web courses inserted through the cleanout pipe and moved forward and backward to remove such obstacle.
Valves can be categorized into the following types, based on their operating mechanism. This is often the only feasible alternative for many rural areas at the present time and in many countries a major portion of the funds available for water systems are allocated to gravity flow systems. Find materials for this course in the pages linked along the left. This pressure wave of high intensity is having the effect of hammering action on the walls of the pipe. To find the coefficient of discharge for orifice meter. In fluid mechanics, reynolds number re is used to categorize the pipe flow regimes as shown above. However, for accurate analyses when density variations are to.
Types of pipe fittings in plumbing system for different. In fact i want to calculate the pressure drop of natural gas through tail pipe by means of hydraulic calculation. Design flow design flow is the maximum flow that can pass through a specified structure safely. Ball valve, for onoff control without pressure drop. A pipe transmits water from a tank a to point c that is lower than water level in the tank by 4 m. Fluid statics, kinematics of fluid, conservation equations and analysis of finite control volume, equations of motion and mechanical energy, principles of physical similarity and dimensional analysis, flow of ideal fluids viscous. The three types of flow through a centrifugal pump are radial flow, axial flow, and mixed flow. Laws of fluid friction darcys equation, minor losses, pipes in series and pipes in parallel. Absolute roughness is important when calculating 4. Generally, a design frequency is selected to match the facilitys cost, amount of traffic. Once this is fixed the design flow magnitude can be determined. Traffic stream characteristics dealing with traffic, therefore, involves an element of variability. Fluid dynamics mechanical engineering mit opencourseware.
The ball is forced over to one side to block the standby inlet by the fluid motion entering through the. Indication of laminar or turbulent flow the term fl tflowrate shldbhould be e reprepldbr ldlaced by reynolds number,where v is the average velocity in the pipe, and l is the characteristic dimension of a flow. Turbulent flow past the seat and plug, when the valve is open, results in a relatively high pressure drop, limited flow capacity, and low recovery. Lets understand how it does this measurement step by step.
Thermodynamic concept, speed of a sound wave, mach number, mach cone and mach angle, flow with friction through pipes, adiabatic and isothermal flow, jet propulsion flow through variable area, flow through nozzle, back pressure variation. The roughness of a pipe is normally specified in either mm or inches and common values range from 0. Laws of fluid friction darcys equation, minor losses pipes in series pipes in parallel total energy line and hydraulic gradient line. Start the pump and wait until water flows through all the sections of the piping network and attains. In determining this design flow the possibility of occurrence has be fixed. Optimization of the manufacturing process dfa is a tool used to select the most cost effective material and process to be used in the production in the early stages of product. The following sections in this article present three excel templates for such calculations.
Viscous flow shear stress, pressure gradient relationship laminar flow between parallel plates laminar flow through circular tubes hagen poiseulles hydraulic and energy gradient flow through pipes darcy weisbachs equation pipe roughness friction factor moodys diagram major and minor losses. E mechanical engineering, second year 3rd semester ce6451 fluid mechanics and machinery previous year question papers for the regulation 20. Laminar flow in a circular pipe from this equation, it is clear that the velocity distribution forms a paraboloid of revolution with u max at r 0. The major loss is that due to frictional resistance of the. Hydraulic design of sewers and storm water drains contd. The velocity of flow through sewers can be determined using mannings formula as below. Since duldr nptel provides elearning through online web and video courses various streams. Ce6451 fluid mechanics and machinery previous year question papers february 23, 2018 may 27, 2019 syed afrith b.
We know back pressure can be calculated by means of hydraulic calculation, flarenet or hysys simulator. For mass transfer from the inner wall of a tube to a moving fluid. The islamic university of gaza environmental engineering. Describing a fluid flow quantitatively makes it necessary to assume that flow variables. The nature of path through the valves and fittings determines the amount of energy losses. Fluid mechanics study notes handwritten engineering study. Flow through pipes 71 friction losses of head in pipes 72 secondary losses of head in pipes 73 flow through pipe systems 71 friction losses of head in pipes. Incompressible viscous flow7 lecture hours d alemberts paradox, viscous stressstrain rate relationship, flow of viscous fluid through circular pipes velocity profiles frictional loss in pipe flowcalculation of minor and major energy losses in pipes. Potential flow boundary layer du dy y u 0 viscous sublayer. Nptel mechanical mechatronics and manufacturing automation. During the compression process, the air moves out of the exhaust valve into the.
Modified hazenwilliams equation is also used in practice. Here we have considered two cross section, first at the inlet and the second one is at the throat. Again, the lateral pipes may contain series of nozzles through which the water comes out as fountain and. In these flows, molecules collide with each other as well. For a flow through a 5 cm diameter pipe, at what velocity will this critical reynolds number appear at 20c. The difference in the pressure heads of these two sections is used to calculate the rate of flow. Flow field may be examined by dividing to two zones. Mass, bernoulli, and energy equations this chapter deals with three equations commonly used in fluid mechanics. Use excel formulas for orifice, venturi meter and ideal. Figure 5 shows the schematic layout of the pipe network to. Reviewed by qiyue lu, research scientist, university of illinois at urbanachampaign on 62619.
Unit 4 flow through nozzles velocity and heat drop, mass discharge through a nozzle, critical pressure ratio and its significance, effect of friction, nozzle efficiency, supersaturated flow, design pressure ratio. Venturi meter and orifice meter are the commonly used flow meters for measuring massvolumetric flow rate or velocity of the flowing fluid. This book is supposed to talk about the fundamentals or introduction level of compressible flow, but the authors. Orifice and venturi meter calculations with excel spreadsheet formulas. Numerical modeling of the transition between free surface. When a liquid is flowing through a long pipe fitted with a vale at the end of the pipe and the valve is closed suddenly a pressure wave of high intensity is produced behind the valve. Different types of pipe fittings in plumbing system various types of pipe fittings are available in plumbing systems for different purposes and functions. Absolute roughness is a measure of the surface roughness of a material which a fluid may flow over. For view pdf file here disabling the download manager or you may also be. A flow of water through channels and pipes of defined characteristics will behave in an entirely predictable fashion, in accord with the laws of hydraulics and fluid flow. The globe and seat construction gives the valve good flow regulation characteristics. When two or more pipes with different diameters are connected together head to tail in series or connected to two common nodes in parallel a.
The flow through a weir, q, is described by the weir equation. The areas of the pipes can be computed as d24, from which. Ce6451 fluid mechanics and machinery previous year. The mass equa tion is an expression of the conservation of mass principle. Numerical modeling of the transition between free surface and pressurized flow in storm sewers jose g. When water flows through a pipe of uniform cross section, the quantity of water passing any point in a given interval of time depends upon the velocity with which the water flows and the area of cross section of the pipe.
Fluid mechanics pdf notes fm pdf notes smartzworld. Mechanical engineering introduction to fluid mechanics. Dfm is the method of design for ease of manufacturing of the collection of parts that will form the product after assembly. Nptel provides elearning through online web and video courses various streams. The lateral pipe may be perforated at the top and side through which the water comes out in the form of spray and spread over the crop in a particular area.
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