A boiler system is an integral component of a thermal power plant and control of water level in the drum of boiler system is a critical operational. The drum water level is the main index in the running for circulating fluidized bed (CFB) boiler, it indirectly reflects the balance relation between boiler load and water supply. If the water level is too low then it will result in boiler drum explosion.However, If the water level is too high, it will affect the separator of steam water and cause damage to the turbine. Therefore, drum water level is too high or too low, which will all result in the serious consequences, and we must take a strict control.
A 3 element proportional integral derivative(PID) control is a popular conventional approach. This scheme works satisfactorily in the absence of any process disturbance. when there are significant process disturbances, the 3-element PID control scheme does not perform well because of lack of knowledge of proper controller gains to cope with such disturbances. Inevitably over time and use, PID controllers get detuned. This project presents a model free approach ,that the performance of existing PID control scheme is observed and collected data is used to gain knowledge about the process. based on this process knowledge, an intelligent control technique, fuzzy logic control(FLC) is developed. This project shows that FLC gives better performance in rejecting process disturbance when compared to 3 element PID control scheme.
Keywords: Boiler drum , level control, PID Controller, Fuzzy logic, Better performance
EXISTING METHOD
In existing scenario to measure the boiler drum level more than two level transmitters are used and the changeover or selection of transmitters to be done by manual by the operator present. On failure of a transmitter which is already being selected may generate alarm and force the level control loop into manual mode. On alert operator should study the condition and to take immediate step to maintain the boiler drum level which many times not possible to maintain the during the transfer period and carrying boiler trip on drum level very low or very high protection.In the existing system PI controller is used to control the drum level in the boiler. The controller requires proper tuning. It is possible only to tune the controller which is suitable for the normal variations in the system. If any major disturbance occurs the controller may not act faster to recover the normal status.
...ed the water begins to boil and steam is produced. When the steam is produced is moved up towards the reactor opening, as it moves up the steam passes through turbines that spin creating energy. The turbines begin to move which is what produces the energy. During this process a lot of steam is produced which is why so much power is created.
With knowledge of a pool boiling curve, it is possible to predict the amount of heat transfer induced by the boiling of a fluid. The level of heat transfer that can be obtained for engineering applications is highly dependent on the difference in temperature between the heating surface and the surrounding fluid. The shape of this curve is dependent on the shape of heating surface as well as the material properties of the heated surface and fluid. Both empirical constants and dimensionless numbers are used to form a boiling curve. Optimal operation conditions for an application can be predicted with the understanding of how different factors can shape the boiling curve [1].
Leading the disaster, Nuclear reactors require an element cooling with a particular finished objective to uproot the created warmth delivered by radioactive rote. Despite when not delivering power, reactors still make some warmth, which must be cleared with a specific end goal to forestall harm to the reactor center. Cooling is by and large refined through fluid stream, water in Chernobyl s case. The issue at the Chernobyl plant was that taking after an emergency shutdown of all force, diesel generators were expected to run the cooling pumps. These generators took around a minute to fulfill full speed, which was respected an inadmissible long time for the reactor to be without cooling. It was recommended that the rotational power of the backing off steam
Anthony, Robert N., and Govindarajan, Vijay. (2005) Management Control Systems. McGraw Hill Companies Inc., New York, NY (pp. 654-655)
Heat transfer from high temperature heated surfaces finds considerable application in engineering. Because of its large number of applications in industries, considerable efforts have been made by researchers to investigate various aspects of the heat transfer and its fundamental principles involved. Fluid flow problems involving heat transfer viz. in presence of convention and radiation represents an idealization of many meaningful problems in engineering practice. Due to the presence of higher level of temperature required in many system like boiler, nuclear reactor; the effect of radiation heat transfer increases. So, there becomes a need of including radiative effect of the participating medium and also their boundary conditions. Keeping this in mind, an attempt was made to investigate the heat transfer in the Indian Pressurized Heavy Water Reactor (IPHWR) during Loss of Coolant Accident (LOCA) with low steam flow. This study will help in estimating the safe working limits for the heat dissipation in the reactor.
Humanity is threatened by the overwhelming growth of science and technology. People are expanding their knowledge through observation and experiment, oblivious to the consequences that result from improper motive. Isaac Asimov—author of The Life and Times of Multivac—uses the science of numbers, or mathematics, as a solution to the fear that arises in a world controlled by a human-like machine. What human beings are afraid of is losing the very word that separates them from everything else in the world—human, and they will do whatever they can to keep that title to themselves.
...he principle numbers of Froude, Reynolds and Weber. Mathematical model predicts the heat and mass transfer in numerical framework for both transports phenomena of relevance to the industry continuous casting tundish system. Additionally, it has an excellent agreement outlet temperature respond the step input temperatures in the inlet stream of water in the tundish model. The simulations of 8x8 grid and 16x16 grid are applied to obtain significant difference between the TAV maps in which both grids are computed by software represent the specific flow of the fluid in the model and the steel caster as the actual size system. Therefore, the physical and mathematical modeling is used as a guidance to build a model before the prototype is constructed in terms of calculation, measurement and determination of specific fluid flow, heat and mass transfer in the water model.
The report is written to explain DSC, the thermal analysis technique. In this technique the differential analysis on the base of reference material is done at different temperature. A very close and similar technique is DTA (Differential Thermal Analysis) . In these technique the material is heated at different temperature although sometimes isothermal analysis also done for specific applications. The temperature is recorded for any heat release or absorption. So the heat capacity is measured at those temperatures. Two possible modes for DSC are power compensation mode and heat flux mode DSC. So, DSC is a technique which measure the heat capacity at various temperature of material and reference.
where L_(make-up) is the mass flow rate of the water from the make-up tank, G_inlet is the mass flow rate of air at the inlet, H_inlet is the humidity of the air at its inlet, G_outlet is the mass flow rate of air at the outlet, and H_outlet is the humidity of the air at its outlet. The amount of make-up water needed for the system can be calculated by determining the loss of water due to evaporation. Using a mass balance of the air flow in tower, the mass flow rate of the water loss, L_loss, can be represented by,
The steam engine is a peripheral ignition mechanism, wherein the operating fluids are disconnected from the ignition results. Non-combustion heat resources like nuclear and solar powers or geothermal power could be utilized. Water resorts to vapour in a reservoir and arrive at high pressures. When developed through turbines or pistons, automatic exertion is completed. The condensed-pressure condensation is then compressed, and reverse-pumped to a boiler. Several convenient steam engines remove low-pressure steams rather than compressing it for recycles.
In process industries control refers to the regulation of all aspects of the process. Precise control of temperature, pressure, level and flow is important in many process applications.
... temperature of 112 0C also and a pressure 2.5 bar. Cooling water is used to condense the vapor exiting column. Remaining methane and hydrogen are separated in reflux drum where the vapor stream is combined with other gases streams. The overhead of first and second separator are combined to form fuel gas. The liquid stream exiting in the bottoms of the reflux drum is pumped at pressure of 3.3 bar for discharging pressure. The pump stream is separated in two streams. One stream is to feed to tray one of the column and the other one stream is cooled down to 38 0C in heat exchanger. Then, the cooled product stream is sent to storage.
The purpose of this report is showing how to apply the control process in the
The equations of motion form the basic building blocks for any system under consideration. These equations should be formulated as accurately as possible to model the desired system. The δinaccuracies in formulating these equations could result in faulty behaviour of the system which could be very difficult to understand. However, modern control systems are designed to accommodate model inaccuracies to a certain degree. It is very important to ensure that our model is modelled within this range. Errors could also enter the system during the calculation stage due to the precision and number of digits used to represent the values.
turbine via interceptor valves and control valves and after expanding enters the L.P. turbine stage via 2 numbers of cross over pipes. In the L.P. stage the steam expands in axially opposite direction to counteract the trust and enters the condenser placed directly below the L.P. turbine. The cooling water flowing throughout the condenser tubes condenses the steam and the condensate collected in the hot well of the condenser. The condensate collected is pumped by means of 3*50% duty condensate pumps through L.P. heaters to deaerator from where the boiler feed pump delivers the water to boiler through H.P. heaters thus forming a closed