Master of crystallography and crystallization october 2012sevilla beatrice. Mod01 lec11 axial flow machine and draft tube duration. A draft tube is essentially used in a reaction turbine to. To take out petrol from tank of bike we use a rubber pipe. Types of cooling towers natural draft and mechanical draft. The draft tube is provided in the central section of the reactor. One end of pipe is dip inside the tank and petrol is sucked from other open end. Types, purpose, function, merits february 2, 2019 february 2, 2019 admin 0 comments. The introduction of the fluid airliquid causes upward motion and results in circulatory flow in the entire reactor. Boiler types and classifications wiki odesie by tech transfer. Draft tube is a diverging tube fitted at the exit of runner of turbine and used to utilize the kinetic energy available with water at the exit of runner.
Different types of draft tubes incorporated in reaction turbines the draft tube is an integral part of a reaction turbine. Jones the key factors in the design of any thermal separation process are the thermodynamics. Draft tube baffle dtb crystallizers, such as the one shown below, are used in applications in which excessive nucleation occurs. The outlet is a specially shaped draft tube that helps decelerate the water and recover kinetic energy. Nptel, an elearning initiative by the 7 indian institutes of technology and the indian institute of science with the support of the mhrd, govt. Metal forming processes indian institute of technology guwahati. Stresses beyond yield strength of the workpiece material is required. It can be used for the cultivation of microbial plant or animal cells. Understanding the different types of cooling towers. This article provides engineering information about the two main types of cooling towers.
The main function of the draft tube is to reduce the water velocity at the time of discharge. Hello fellow wikipedians, i have just modified one external link on draft tube. The efficiency of the draft tube can be said as it is the ratio of actual conversion of kinetic energy into the pressure energy in the draft tube to the kinetic energy available at the inlet to the draft tube. The 10minute guide to learning the basics of fired heaters. Draft tube gas technologies turbomachinery free 30. Air ows up the riser tube, forming bubbles, and exhaust gas is. Set the turbine above the tailrace without any appreciable drop in. The draft tube works by converting some of the kinetic energy at the exit of the turbine runner into the useful pressure energy. Crystallizers visual encyclopedia of chemical engineering. How to download all of the lectures in pdf for a course in. A draft tube is a kind of tube which connects or acts as an intermediately between the water turbine exit and tail race.
The other zone that receives no gas is the down comer. The upper steam capacity of fire tube boilers is about 20,000 ibmhr, and the peak pressure. You can find them according to your branch and subject in the below link national mission on education through ict this was initiated by iit madras. Apr 05, 2019 a draft tube is a kind of tube which connects or acts as an intermediately between the water turbine exit and tail race. Boilers are classified as highpressure or lowpressure and steam boiler or hot water boiler. Me 416516 cleaverbrooks horizontal, fourpass, forced draft fire tube boiler.
Using a draft tube also has the advantages of placing the turbine structure above the tail race so that any required inspections can be made more easily and reducing the amount of excavation required for construction. Actual conversion of kinetic energy into pressure energy kinetic energy available at. Draft tube is a diverging tube fitted at the exit of runner of turbine and used to utilize the kinetic. Hydraulics and hydraulic machinery notes pdf hhm pdf notes hhm notes pdf file to download are listed below please check it. Draft tube definition, working, application and types. Jan 23, 2018 mod01 lec11 axial flow machine and draft tube duration. Nptel provides elearning through online web and video courses various streams. The upper steam capacity of fire tube boilers is about 20,000 ibmhr, and the peak pressure obtainable is limited by their large shells to about 300 psi. The water exits the cooling tower and is sent back to the exchangers or to other units for further cooling. To better help you understand the differences between the different types of cooling towers available today, weve compiled this quick guide.
Hydraulics and hydraulic machinery notes pdf hhm notes pdf. In the airlift bioreactors, the medium of the vessel is divided into two interconnected zones by means of a baffle or draft tube. The turbine does not need to be at the lowest point of water flow as long as the draft tube remains full of water. Actual conversion of kinetic energy into pressure energy kinetic energy available at the inlet of the draft tube. You will find all pdf s and also as mp3 file for all video lectures which are in nptel. The airliquid velocities will be low and hence the energy consumption is also low. The draft tube is a conduit which connects the runner exit to the tail race where the water is being finally discharged from the turbine. Fire tube boiler 1800 the fire tube boiler, the oldest design, is made so the products of combustion pass through tubes surrounded by water in a shell.
Cooling tower types cooling towers fall into two main categories. The other zone that receives no gas is called downcomer. The furnaceflame volume can either be inside or external to the shell that contains the water. Draft tube and cavitations, performance of turbines, similarity laws, centrifugal pump, minimum speed to start the pump, multistage pumps, jet and submersible pumps, positive displacement pumps, reciprocating pump, negative slip, flow separation conditions, air vessels, indicator diagram and its variation, savings in work done, rotary pumps. Draft tube is a divergent tube one end of which is connected to the outlet. The efficiency of the draft tube can be said as it is the ratio of actual conversion of kinetic energy into the pressure energy in the draft tube to the kinetic energy available at the inlet to the draft tube so this means. Master of crystallography and crystallization october 2012. Typical closed loop cooling tower system is shown in figure 7. Small, unwanted crystals, called fines, are removed from larger particles using gravitational settling and recycled through the crystallizer again, resulting in maximum crystal recovery and larger crystals.
Draft tube is a connecting pipe of constantly increasing area, from runner exit to tail race. On this page we discuss the introduction to cooling towers and the principle of operation. Sep 05, 20 for the love of physics walter lewin may 16, 2011 duration. The following data refers to an elbow type draft tube, the area of the circular inlet is 25 metres square, the area of the rectangle outlet is 116 metre square and the velocity of water at inlet to the draft tube is 10 metre per second. Lecture on francis turbine indian institute of technology.
The function of the draft tube in a reaction turbine is. A conical type draft tube attached to a francis turbine has an inlet diameter of 3 m and its area at outlet is 20 m. A higher turbine location, however, increases the suction that is imparted on the turbine blades by the draft tube. We look at how the size of the spray affects efficiency and note the two common forms of, natural draft cooling towers, which are the spray type and the surprisingly more. A hot water boiler, strictly speaking, is not a boiler. Hydraulics and hydraulic machinery notes pdf hhm notes pdf hydraulics and hydraulic machinery notes pdf hhm notes pdf. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple faq for additional information. As their name implies, natural draft cooling towers rely on natural convection to circulate air throughout the tower, which then cools the water. The dispersion flows up the riser zone while the down flow occurs in the down comer. The draft tube is an expanding tube which is used to discharge the water through the runner and next to the tailrace. Introduction to fluid machines lectures 49 to 53 3 4 54. Unesco eolss sample chapter chemical engineering and chemical process technology heat and mass transfer operations crystallization j. Only one of the two zones is sparged with air or other gas and this sparged zone is known as the riser. In one of the two zones referred to a riser, the airgas is pumped.
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