INTRODUCTION

A heat pipe is a device that efficiently transports thermal energy from its one point to the other. It utilizes the latent heat of the vaporized working fluid instead of the sensible heat. As a result, the effective thermal conductivity may be several orders of magnitudes higher than that of the good solid conductors. A heat pipe consists of a sealed container, a wick structure, a small amount of working fluid that is just sufficient to saturate the wick and it is in equilibrium with its own vapor. The operating pressure inside the heat pipe is the vapor pressure of its working fluid. The length of the heat pipe can be divided into three parts viz. evaporator section, adiabatic section and condenser section. In a standard heat pipe, the inside of the container is lined with a wicking material. Space for the vapor travel is provided inside the container.

Basic components of a heat pipe

The basic components of a heat pipe are
1. The container
2. The working fluid
3. The wick or capillary structure

Container

The function of the container is to isolate the working fluid from the outside environment. It has to be there for leak proof, maintain the pressure differential across the walls, and enable transfer of thermal energy to take place from and into the working fluid.

The prime requirements are:
1. Compatibility (Both with working fluid and External environment)
2. Porosity
3. Wettability
4. Ease of fabrication including welding, machinability and ductility
5. Thermal conductivity
6. Strength to weight ratio

The working fluid

The first consideration in the identification of the working fluid is the operating vapor temperature range. Within the approximate temperature band, several possible working fluids may exist and a variety of characteristics must be examined in order to determine the most acceptable of these fluids for the application considered.

The prime requirements are:
7. Compatibility with wick and wall materials
8. Good thermal stability
9. Wettability of wick and wall materials
10. High latent heat
11. High thermal conductivity
12. Low liquid and vapor viscosities
13. High surface tension

Wick

The wick structure in a heat pipe facilitates liquid return from the evaporator from the condenser. The main purposes of wick are to generate the capillary pressure, and to distribute the liquid around the evaporator section of heat pipe. The commonly used wick structure is a wrapped screen wick.

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APPLICATION OF SMART MATERIALS IN MODERN ENGINEERING FIELDS

Structural Applications of Smart Materials in Construction Engineering Using Robotics

ABSTRACT

Sensors and Actuators designs have mimicked nature to a large extent. Similar to our five senses – sight, sound, smell, taste and touch -correspondingly visual/optical, acoustic/ultrasonic, electrical, chemical and thermal/magnetic sensors have been developed. The response from these primary sensors is converted to electrical signals, which are transmitted to the brain (central processing unit) for further processing. In addition to the processing, the role of the processor is to make decision based on these inputs. This is currently done manually by an experienced operator who has an understanding of the sensing and processing technology. To aid the operator in making a more judicious decision, the conditioned signal has to be presented with as much pertinent information displayed in an arresting way. A further development would be to provide the virtual machine itself to make the judgment – smart sensor. The next stage in this would be for the processor to decide on the course of action and the actuation mechanism to respond accordingly. Virtual human robots can be equipped with sensors, memory, perception, and behavioral motor. This eventually makes these virtual human robots to act or react to events. The design of a behavioral animation system raises questions about creating autonomous actors, endowing them with perception, selecting their actions, their motor control and making their behavior believable and the behavior should be spontaneous and unpredictable.

INTRODUCTION

There is an increasing awareness of the benefits to be derived from the development and exploitation of smart materials and structures in applications ranging from hydrospace to aerospace. With the ability to respond autonomously to changes in their environment, smart systems can offer a simplified approach to the control of various material and system characteristics such as light transmission, viscosity, strain, noise and vibration etc. depending on the smart materials used [1]. There are a number of materials that act as both sensors and actuators that can monitor and respond to their environment. However, with the ability to also modify their properties in response to an environmental change, they can be ‘very smart’ and, in effect, learn. While the scope of sensors and actuators is quite broad, three main sub-programs have been identified – Smart Structures and Materials, Miniature Sensor and Actuators and Automated Testing, Inspection Monitoring and Evaluation. These are exciting times for Sensors and Actuators with the maturing of the enabling technologies of Photonics and Electronics paving the way for inventive and innovative system designs. For the modelling of sensor behaviours, the ultimate objective is to build intelligent autonomous virtual humans with adaptation, perception and memory. These virtual humans should be able to act freely and emotionally. They should be conscious and unpredictable. The virtual humans are expected in the near future to represent computer the concepts of behaviour, intelligence, autonomy, adaptation, perception, memory, freedom, emotion, consciousness, and unpredictability. Behaviour for virtual humans may be defined as a manner of conducting themselves. It is also the response of an individual, group, or species to its environment.
Intelligence may be defined as the ability to learn or understand or to deal with new or trying situations[1].

A. Mechatronic devices

The essential ingredients of any robotic system are sensors, computation and actuators. Appropriate choices of sensors and actuators can simplify a robotic system or may even be the difference between its success and failure. Mechatronic devices are the novel actuators including those based on shape memory alloy, electrorheological fluids, magnetic fluids and the piezoelectic effect as well as a wide range of sensors for measuring quantities of importance for robotic systems [1].

B. Robotic mechanisms

All of the sensors, actuators [1]-[2] and algorithms that are developed should be tested by incorporating them into a mobile robot platform, humanoid robot or fixed manipulator/ gripper system. An extensive experience of building legged, wheeled and tracked land vehicles, submersibles and flying robots as well as robotic grippers and complete humanoid robots are required.

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INTRODUCTION

Since the world’s resources of material and energy are getting progressively, by necessity, there is growing involvement in studies of wear on a global basis. Wear of sliding components result in reduced mechanical efficiency and an irretrievable loss of material in the form of wear debris. Wear at the interface between moving particles is a normal characteristic of machine operation. The kind and rate of wear depend on the machine type. Lubrication is provided between the moving surface to minimize the wear but during operations millions minute wear particles entering the lubricating oil. These particles are in suspension in the oil, larger particles may be trapped by filter while others generally too small to be removed, remain in suspension in the circulating oil.

Condition based monitoring has, in the past, been referred to as an art, when quite clearly it is a science, and despites the cost of machine, surprisingly little attention has been devoted to this science from the viewpoint of understanding and modeling failure mechanisms and the study of probability to failure. Predictive maintenance technique has now become common exercises as they maximize the machine availability time and minimize the cost of maintenance, since the machine can be stopped just before as impending problem in an other wise healthy machine

Fault detection using vibration analysis is difficult in very low speed – high load noisy machines. In the case of slow speed bearing the vibration generated by damaged components is very low, usually close to the floor noise and difficult to identify. In these situations, Wear Debris Analysis has proven useful in providing supporting evidence on the bearing or gear status. It also provides information on the wear mechanism, which is involved.

Sliding adhesive wear particles are found in most lubricating oils. They are an indication of normal wear. They are produced in large numbers when one metal surface moves across another. The particles are seen as thin asymmetrical flakes of metals with highly polished surfaces.

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INTRODUCTION

The history of antimatter begins with a young physicist named Paul A.M.Dirac (1902-1984) and the strange implications of a mathematical equation. This British physicist formulated a theory for the motion of the electrons in electric and magnetic fields. Such theories had been formulated before, but what was unique about Dirac’s was that his included the effects of Einstein’s Special Theory of Relativity. This theory was formulated by him in 1928.Mean while he wrote down an equation, which combined quantum theory and special relativity, to describe the behavior of the electron. Dirac’s equation won him a Nobel prize in I 933,but also posed another problem; just at the equation x2 = 4 can have two solutions (x 2, x = -2). So Dirac’s equation would have two solutions, one for an electron with positive energy, and one for an electron with negative energy. This led theory led to a surprising prediction that the electron must have an “antiparticle” having the same mass but a positive electric charge.

1n 1932, Carl Anderson observed this new particle experimentally and it was named “positron”. This was the first known example of antimatter. In 1955, the anti proton was produced at the Berkeley Bevatron, and in 1995, scientists created the first anti hydrogen atom at the CERN research facility in Europe by combining the anti proton with a positron Dirac’s equation predicted that all of the fundamental particles in nature must have a corresponding “Antiparticle”. In each case, the masses of the particle and anti particle are identical and other properties are nearly identical. But in all cases, the mathematical signs of some property are reversed. Anti protons, for example have the same mass as a proton, but the opposite electric charge. Since Dirac’s time, scores of these particle-antiparticle pairings have been observed. Even particles that have no electrical charge such as the neutron have anti particle.

ANTIMATTER PRODUCTION

Anti protons do not exist in nature and currently are produced only by energetic particle collision conducted at large accelerator facilities (e.g. Fermi National Accelerator Laboratory, Fermi Lab, in US or CERN in Geneva, Switzerland). This process typically involves accelerating protons to relativistic velocities (very near to speed of light) and slamming them into a metal (e.g. Tungsten) target. The high-energy protons are slowed or stopped by collisions with nuclei of the target; the kinetic energy of the rapidly moving protons is converted into matter in the form of various subatomic particles, some of which are anti protons. Finally, the anti protons are electro magnetically separated from the other particles, then they are captured and cooled (slowed) by a Radio-Frequency Quadrapole (RFQ) linear accelerator (operated as a decelerator) and then stored in a storage cell called as a Penning Trap.

Note that anti protons annihilate spontaneously when brought into contact with normal matter, thus they must be stored and handled carefully. Currently the highest anti proton production level is in the order of nano-grams per year.

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ABSTRACT

In this era of increasing fuel prices, here a device called ‘FUEL ENERGIZER’ help us to Reduce Petrol /Diesel /Cooking gas consumption up to 28%, or in other words this would equal to buying the fuel up to 28% cheaper prices.When fuel flow through powerful magnetic field created by Magnetizer Fuel Energizer, The hydrocarbons change their orientation and molecules in them change their configuration. Result: Molecules get realigned, and actively into locked with oxygen during combustion to produce a near complete burning of fuel in combustion chamber.

INTRODUCTION

Today’s hydrocarbon fuels leave a natural deposit of carbon residue that clogs carburetor, fuel injector, leading to reduced efficiency and wasted fuel. Pinging, stalling, loss of horsepower and greatly decreased mileage on cars are very noticeable. The same is true of home heating units where improper combustion wasted fuel (gas) and cost, money in poor efficiency and repairs due to build-up.

Most fuels for internal combustion engine are liquid, fuels do not combust until they are vaporized and mixed with air. Most emission motor vehicle consists of unburned hydrocarbons, carbon monoxide and
oxides of nitrogen. Unburned hydrocarbon and oxides of nitrogen react in the atmosphere and create smog. Smog is prime cause of eye and throat irritation, noxious smell, plat damage and decreased visibility. Oxides of nitrogen are also toxic.

Generally fuels for internal combustion engine is compound of molecules. Each molecule consists of a number of atoms made up of
number of nucleus and electrons, which orbit their nucleus. Magnetic movements already exist in their molecules and they therefore already have positive and negative electrical charges. However these molecules have not been realigned, the fuel is not actively inter locked with oxygen during combustion, the fuel molecule or hydrocarbon chains must be ionized and realigned. The ionization and realignment is achieved through the application of magnetic field created by ‘Fuel Energizer’

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