A study on the application of a cooling water physical model

Pump intake structures are a necessary component of the cooling water systems for power plants, process and manufacturing facilities, flood control and water/wastewater applications. Large cooling water systems often use substantial sea / river water intakes or cooling towers to provide the required cooling of the process or circulating water. These structures can be very large and often house multiple pump with capacities ranging in size from a few hundred m3/hr to 60,000 m3/hr or more. With such large flow rates care must be taken to ensure uniform flow to the pump to limit vortex activity, vibration, flow induced cavitation and performance problems. In many cases, a physical hydraulic model study is conducted to evaluate the overall approach flow and the performance of the intake. This paper presents a synopsis of several recent physical model studies and a review of recurring problems associated with common design features. This paper takes a closer look at stop log support walls, an intake design feature common to seawater intakes. This wall is often used to minimize the height of the stop logs. In applications with large variations of water level, such as a seawater intake, there are times when the support walls are submerged significantly, resulting in significant flow disturbances. A feature common to cooling towers is the use of 90-degree suction elbows to supply horizontal pumps. A review of short radius vs. long radius elbow performance is presented. Cooling towers often have another common feature which is a significant difference in depth between the cooling tower basin and the pump sump. This results in typical shallow basins and deeper sumps. A common problem is the utilization of minimum pump submergence to set the water levels without reference to the basin invert elevation. A discussion of choked flow conditions in cooling towers is presented. A final discussion is presented regarding cross-flow and the use of concentrated supply channels in cooling tower applications to facilitate the isolation of individual tower cells. This paper presents a synopsis of several recent physical model studies and a review of recurring problems associated with common intake design features. The results of several model studies are presented to demonstrate the negative impacts that these common intake features have on approach flow conditions. The intent of the paper is to provide the design engineer some additional guidance not offered in industry guidelines or standards with the hope of avoiding common problems which can be costly and difficult to remediate after the intake has been constructed.

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MATHEMATICAL MODEL FOR THE HEAT EXCHANGE OF GREENHOUSE AND SOLARIUM SOIL IN THE PLANT ROOT AREA

Proccedings of International Scientific Conference "RURAL DEVELOPMENT 2017" ◽

10.15544/rd.2017.001 ◽

2018 ◽

Author(s):

Petru CÂRDEI ◽

Dragoș MANEA

Keyword(s):

Mathematical Model ◽

Heat Exchange ◽

Physical Model ◽

Plant Root ◽

Three Dimensional ◽

Cooling Water ◽

Cooling Fluid ◽

Root Area ◽

Copper Pipe ◽

Complex Approach

This paper proposes a structural mathematical model of heat exchange into the soil of a solarium. The model investigates the possibility of a rational choice of the cooling water transit time through the pipeline network located in the plant root area. Also, the size of the cooled root area is roughly determined, according to the temperature of the cooling fluid. At the same time, the model provides information on the degree of soil cooling, meaning the ratio between the average soil temperature in the cooled root area and a reference temperature, for example the temperature indicated by a sensor into the soil, at a distance fixed to the root axis. The model considered is a plan one. Geometric is considered a section through the soil, perpendicular to the axis of the pipe carrying the cooling fluid. The soil, the copper pipe and the water are the components of the model. The finite elements for meshing are flat, triangular. This simple model prepares a three-dimensional complex approach and has, as a preparation, a unidimensional model. Obviously, this model provides some start-up indications for achieving the physical model and content of the process parameter set. After its realization, the physical model will be used for the optimal control of the cooling process in the radicular area, but also for the validation and the improvement of the theoretical model.

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DISSIPATION OF WAVE ENERGY IN A SEAWATER OUTFALL CHANNEL

Coastal Engineering Proceedings ◽

10.9753/icce.v18.131 ◽

1982 ◽

Vol 1 (18) ◽

pp. 131

Author(s):

K.G. Witthaus ◽

G. De F. Retief ◽

G.K. Prestedge ◽

L.R. Huskins

Keyword(s):

Physical Model ◽

Wave Energy ◽

Cooling Water ◽

Head Loss ◽

Wave Action ◽

Power Station ◽

Energy Dissipator ◽

Rubble Mound

This paper describes the investigation of means of reducing wave action reaching the shoreward end of a power station cooling water outfall channel without resulting in significant head loss to the outflowing water. A variety of conceptual methods of reducing wave action in the outfall channel was examined. A physical model of the outfall was constructed. It was found that a rubble mound wave energy dissipator located in the outfall channel dramatically reduced wave action at the discharge seal pit.

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A SYSTEM FOR PROTECTING AN OIL DIFFUSION PUMP AGAINST FAILURE OF THE MECHANICAL FORE PUMP, COOLING WATER, OR ELECTRICITY

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068710 ◽

1970 ◽

Vol 28 ◽

pp. 344-345

Author(s):

W. C. Bigelow ◽

F. B. Drogosz ◽

S. Nitschke

Keyword(s):

High Vacuum ◽

Cooling Water ◽

Effective Protection ◽

Pump Line ◽

Diffusion Pump ◽

System Pressure ◽

Control Relay ◽

Vacuum Systems ◽

Vacuum Gage ◽

Pressure Switch

High vacuum systems with oil diffusion pumps usually have a pressure switch to protect against Insufficient cooling water; however, If left unattended for long periods of time, failure of the mechanical fore pump can occur with equally serious results. The device shown schematically in Fig. 1 has been found to give effective protection against both these failures, yet it is inexpensive and relatively simple to build and operate.With this system, pressure in the fore pump line is measured by thermocouple vacuum gage TVG (CVC G.TC-004) whose output is monitored by meter relay MRy (Weston 1092 Sensitrol) which is set to close if the pressure rises above about 0.2 torr. This energizes control relay CRy (Potter & Brumfield KA5Y 120VAC SPDT) cutting off power to solenoid-operated fore line valve Vf (Cenco 94280-4 Norm. Closed) which closes to prevent further leakage of air into the diffusion pump

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Dispersion of Cooling Water From a Coastal LNG Plant

Coastal Engineering 1980 ◽

10.1061/9780872622647.168 ◽

1980 ◽

Author(s):

P. Ackers ◽

J.D. Pitt ◽

G. Thompson ◽

K.G. Rippin

Keyword(s):

Cooling Water

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EXPERIMENTAL STUDIES OF CAR PROPERTIES ON A PHYSICAL MODEL

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2019-4-260-10-16 ◽

2019 ◽

pp. 10-16

Author(s):

Oleksii Timkov ◽

Dmytro Yashchenko ◽

Volodymyr Bosenko

Keyword(s):

Mathematical Model ◽

Remote Control ◽

Physical Model ◽

Model Experiment ◽

Experimental Studies ◽

Electrical Energy ◽

Short Term ◽

Motor Current ◽

Memory Card ◽

The Mathematical Model

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.

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