Energy Transfer and Thermodynamics.

It needs to be at least 2500 words. On the other hand, a grey surface does not fully emit heat energy and has an emissivity value less than 1. The view factor affects the rate of heat transfer because the real-life intercepted by an area from a point on another site is dependent on the solid angle with which the end views the area. A black body is a material that is a perfect emitter of heat energy and has an emissivity value of 1.Define heat of combustion, heat release rate, and combustion reaction giving appropriate equations. Explain the different explosions and definitions of specific heat capacity, latent heat, calorimetry, combustion temperature, and chemical equilibrium. (8 Marks)Ans:Definitions:The heat of combustion is the amount of heat released per unit mass or unit volume when the substance is completely burned.The heat release rate is the rate at which an object releases heat.A combustion reaction is when all substances in a compound combine with oxygen and burns.Specific heat capacity is the amount of heat energy required to raise a body’s temperature per unit of mass.Latent heat is the quantity of heat absorbed or released by a substance changing state.Calorimetry is the measurement of the amount of heat evolved or absorbed in a chemical reaction, change of state, or solution formation.Combustion temperature is the lowest temperature at which a substance will burn.Chemical equilibrium is when a chemical reaction occurs at equal rates in its forward and reverse directions. The concentrations of the reacting substances do not change with time.Different types of combustion:Spontaneous – happens at even room temperature when enough vapor of the material and enough oxygen have collected in a confined space to allow rapid oxidation (combustion) to start and continue.Flash – happens when enough vapor has collected to burn at a specific elevated temperature but not enough to continue.Fire – happens at a higher temperature when the combustion for the bacterial to continually give off vapor from the material.&nbsp.Determine the rate of heat transfer per unit area for a blackbody at 20C. Is a good absorber of radiation a good emitter or a poor emitter? (2 Marks)Ans:&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp. First, express the temperature in absolute scale:&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp. T = 20C = 293 K&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp. _ = 5.67 x 10-8 W/m2 K4rate of heat transfer per unit area:&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp. &nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp.&nbsp. q = (_*T4) = [5.67 x 10-8 * (293)4] = 417.88 W/m2&nbsp

Nonlinear and Negative Resistance in Loose Electrical Contacts the Dark Bridge.

  An analysis of the dark bridge in loose electrical contacts reveals nonlinear and negative resistance. This article gives a critical review of the nonlinear and negative resistance in loose electrical contacts dark bridge. The review includes the introduction, research, critical analysis and finally, the conclusion.The authors intention of writing the article was to survey and summarise research on a topic in the engineering field. The summary and analysis give a detailed outline of the voltage-current (V-I) relationship as well as the diameter and thickness of the black bridge. The findings should reveal a nonlinear and negative resistance in loose electrical contacts at a range of definite values. This article in relation to other works in the same field is important for it provides critical information that will guide designers in their design work especially designers of printed circuit boards. The authors, who are graduate students, outline their points and support them accordingly in a manner that is easily grasped by the learner.Electrical contact can be defined as a releasable junction between two conductors which is apt to carry electric energy. (Holm, 1981). Electrical contacts are quite crucial for every electrical system for which inefficiency due to contact failure is common. The degradation may be as a result of the improper design of the points of contact or of the contacts themselves. (Kubota and Sasaki et al., 2013) Michael Brumbach in his book, Industrial Maintenance, maintains that mechanical vibrations cause electrical connections to loosen over time. Loose electrical connections cause high resistance connections that result in heat build-up and failure of the termination. (Brumbach and Clade, 2003)Loose electrical connections and broken wires can be a cause of the electrical fire. This happens as follows

CAT Aircraft Make Use of Weather Radar.

Need help with my writing homework on CAT Aircraft Make Use of Weather Radar. Write a 3000 word paper answering; Clear-Air Turbulence (CAT): when air masses have a turbulent movement where there are no visual cues that look like the clouds. The meeting of the air actually is the cause of the turbulence and this air move widely at different speeds.It is not easy for the standard airplane radars to detect CAT. This because the CAT should have some association with the clouds that normally show a movement of air that cannot be predicted. When with cloud covers, the Clear-air Turbulence normally appears differently. This makes it not to be visible for both the eye and again. it cannot be measured with the sensors. Research shows that similar turbulence is likely to occur in the future several times or repeatedly because of a change in the climate. As a normal happening, there’s an occurrence of wind shear along the stream of the jet. In this case, several layers of air that are extended normally move in a horizontal manner, going against one another and taking totally different speeds. It is proved that strong wind shear can also create breaking waves such as those waves found on the water. Due to the breakages of such waves, there is normally the creation of vortices in the air or turbulence which are associated with clear air.When there are lights and ranging instruments that are installed in the aircraft, laser-based is the one responsible for detecting such. To determine the density of the air, there’s the use of the backscatter values that are measured for air molecules, nitrogen, and oxygen. This is also enabled through the emission of UV short-wave radiations following the flight direction. The information on turbulence, mostly in distant areas, is then provided by the fact that there is a fluctuation in the density. This usually makes it just for the first time to be visible and very predictable

Aircraft Fuel System

Need help with my writing homework on Aircraft Fuel System. Write a 3000 word paper answering; The system adds considerable wiring to the system since it needs a separate power supply for backup the alternator. Due to the extra weight of parts of the full authority digital engine control, the balance, and valerate value have to be checked and recalculated. There are additional cockpit controls and switches to control the fuel pump with FADEC power supply, protecting them (BTEC Unit 81 handout). The ECU uses a 3D memory map in controlling the injection of appropriate fuel amount, taking into consideration varied ambient circumstances, such as air pressure density and the air temperature, throttle settings, and RPM. The ECU can sense barometric pressure and, in response, compensates for the appropriate fuel amount to be injected. The spark plug ignition timing is regulated depending on throttle settings for each load. The variations in ignition timing yield faster engine start-up and smooth operations with the variable loads. The FADEC engine does not require choking during engine start since the ECU regulates fall fuel cylinders and helps in retarding the ignition. FADEC system replaces the carburetor. In this case, the ignition does not wholly depend on the aircraft’s electrical system. It combines well with the design of fuel injection (Federal Aviation Administration).On the other hand, the hydro-mechanical control system makes the driver control the power plant of the aircraft by utilizing an internal combustion engine. The sets of sensors and control are the alternator master and the battery master. The battery master activates the battery contractor that links the battery to the electrical bus aircraft. In contrast, the master alternator supplies power to the alternator’s field circuit to start it (BTEC Unit 81 handout). The two switches are the source of energy to the aircraft systems. The throttle sets up the power level required and controls the massive airflow rate in the carbureted engines that are to be delivered to the cylinder. Pitch control makes adjustments to the speed unit, which, in effect, adjusts the pitch of the propeller and works to control the load required by the engine for maintaining the RPM.

key features of emulsion Paper

Hi, I am looking for someone to write an article on the key features of emulsion Paper must be at least 3000 words. Please, no plagiarized work! The process of forming emulsions is dependent on the following factors:1. The distribution of the size of the particles and the difference in the density of the droplets and the medium being used.2. The magnitude of forces of attraction in comparison to the forces of repulsion which determines the level of flocculation.3. The level of solubility of the droplets. This determines the Oswald ripening of the mixture.4. The level of stability between the droplets and in turn this determines the coalescence and the phase inversion.When separating two immiscible liquids such as crude oil and water, there is a need to use additional processes in addition to the separation of mixtures through the means of gravity. In order to determine the most appropriate method to use in the separation of mixtures, the following factors must be taken into consideration:1. The tightness of the emulsion. 2. The specific gravity of the crude oil and the water in the mixture. 3. The level of corrosiveness of the crude oil, the water, and the casing head gas. 4. The tendency of scaling the produced water. 5. The amount of fluid that is meant to be treated and the percentage of water that is available in the fluid.6. The tendency of crude oil to form paraffin. 7. The amount of operating pressure that the equipment can sustain during its operations. 8. The availability of the outlets of sales and products and the market value for the head gas of the casing.&nbsp.The most common method for separating the water-oil emulsions is the application of heat on the stream thus increasing the temperature of the two liquids that are immiscible and this may deactivate the agents that are used in demulsifying the mixture. This method allows the dispersed droplets of water to collide. As the process of collision occurs, the droplets increase in size and as they become more bulk they begin to settle (Binks, 1998). If the emulsion is properly designed, the water will eventually settle at the bottom of the container that is being used to treat the mixture. This occurrence is usually a result of the differences in the specific gravity of the two liquids.For an emulsion to exist, the following components must exist. two liquids that are mutually immiscible, an agent to be used for emulsification, and agitation that is sufficient in order to disperse the discontinuous phase into the continuous phase.&nbsp. In the case of the production of oil, the two liquids that are mutually immiscible are both oil and water (Tadros, 2005). The agents that are used in the process of emulsification of the mixture may include. small particles of solids, paraffin, and asphaltenes are usually always present in the formation of the fluids and a sufficient agitation always occurs as the fluid makes its way into the bore of the well up through the tubing and the surface choke. The main difficulty experienced during the separation of these emulsions is a dependency on the stability of the emulsion.

Engine Strip and Build.

Provide a 10 pages analysis while answering the following question: Engine Strip and Build. Prepare this assignment according to the guidelines found in the APA Style Guide. An abstract is required. The tank eased up and the rubber was also removed. Finally, bolts and nuts were replaced on the tank fittings. The tools that were used are a 10mm spanner, extension and 10mm socketAir cleaner and housing were removed by loosening the wing nuts. Then throttle handle was removed by loosening 2 *M6 nuts holding the lever and, 2 bolts on the linkages were also removed. The spring that withdraws the lever was also removed. The breather was then disconnected.The carburetor was removed from the studs, rods and a small spring was also removed. The position of the governor was also marked. Gaskets and Plastic spacer were removed at the same time noting their orientation and position. Bolts and nuts were replaced. The tools that were used for this procedure were. 10mm socket, ratchet, extension and 10mm spanner4pieces of M6 bolts were and the cover was lifted carefully to ensure that the gasket is not damaged. The plug head was pulled off and the spark plug using a spark plug socket and unscrewed using hand. The tools that were used in this procedure were sparkplug socket, (21mm), 10mm socket and 10 mm Ratchet extension4 pieces of M8 bolts are removed whereby 2 are located at the rocker box, the procedure of undoing the bolts was done in a diagonal manner. The cylinder head and gasket were removed carefully, watching the push roads and dowels. Finally, the bucket shim on the exhaust valve was removed and parts set aside carefully. The following tools were used Extension socket and Tommy barThe material that is used to make the alternator bracket is an alloy of cast iron. Cast iron is preferred because of its strength, cost, and ease of casting it. Alternator bracket should be made of very strong materials because its carrying an alternator that is connected to the engine pulley by a high tension v-belts, the bracket is also subjected to vibration because when the belt is in use, its elastic properties cause the bracket to vibrate.

Stubs and Drivers in Automated Software Testing.

To begin with, the state of many operating environments of software systems is such that any vulnerability is likely to attract exploits (Paul, 2012). This calls for software testers that are focused, diligent, and thorough to ensure that the delivered software products do harbor any vulnerability. Just like the software testers, hackers constantly make efforts to have their hacking skills updated. With such an effort, hackers increase their ability to identify and exploit newer system vulnerabilities. Thus, testing like a hacker means that a software tester assumes the role of a hacker to be better placed in identifying the security hitches of a system.Secondly, hackers have the main intention of doing what other people have not been able to do and this is why they able to discover system vulnerabilities. To counteract such intentions, testers have to think outside the box about the possible system weakness that attackers and hackers can find attractive. Nothing would be as paining as a tester carrying out a vulnerability assessment only for someone to come after him to find something that he failed to identify. Furthermore, the focus, time, and effort spent in a testing activity will dictate the success level of a software project. Based on these facts, testing like a hacker means that a software tester in his effort to eliminate system weaknesses might need to go beyond the testing scope specified in the Test Plan.Finally, the exploitation is known to be a mission for circumventing the security controls of a system by launching an exploit. In the software world, exploits are bugs or issues within the software code that allow hackers to execute or launch payloads against the target software system (P, 2013). Payload here refers to a means of having the target machine turned into a puppet and forcing it to make our wishes. The payloads have the danger of altering the intended software functionality and allowing hackers to do other things like opening back doors to the compromised systems.

experiment on the determination of tensile strength of metals

Compose a 2000 words assignment on the experiment on the determination of tensile strength of metals. Needs to be plagiarism free! The values obtained are plotted on different graphs for each metal. The graphs are of the applied load against the displacement. Finally, the yielding points of the metals are determined from the charts together with the maximum load-carrying capacity of the metals.In determining the mechanical properties of materials, carefully designed experiments are conducted in the laboratories. The experiments are so designed that they replicate the service conditions in a very close range. Load application on materials involves many factors considered in the real life. The modes, in which loads are applied, include some typical examples like tensile, shear and compressive. These properties are of much importance in material selection for mechanical design. There are other factors like time and temperature that complicate the design process.As from the topic of this laboratory experiment, the report is confined to the tensile properties of metals. Figure 1 below shows a tensile testing machine with features similar to the one used to conduct this experiment. A specimen of standard dimensions and shape is subjected to an axial load. A doge-bone-shaped specimen is gripped at its two ends and pulled apart during a typical tensile experiment to elongate at a determined rate to its breakpoint. In the process, a highly ductile material may make it difficult to reach its break point. The tensile tester used here for the experiment is manufactured by Instron (model 5569) with a variable pulling rate and a maximum load of 50kN. Different types of mechanical testing can be accommodated by the machine only by changing the setup of the experiment according to the ASTM standards.A plot of stress (_) versus strain (_) is conducted during the tensile test experiment for analytical purposes. The plot can automatically be generated by the software provided by the instrument manufacturer. From the metric system, stress is measured in N/m2 or Pa, whereby 1 N/m2=1Pa.&nbsp

comparing rigidizing methods using re enforced material Paper must be at least 2000 words

Please, no plagiarized work! Carbon fibers are the best to use in the reinforcement because they induce higher stiffness, general strength, and effective fatigue and durability properties [8]. Glass fibers are more effective in achieving shear strengthening. Various methods can be used in the reinforcement of polymers using carbon or glass fibers. Some of the methods include curing pressure increase and filler incorporation and vacuum infusion. This ridging method enhances the through-thickness thermal conductivity of carbon fiber polymer-matrix. This method is used to increase heat dissipation by enhancing the low through-thickness thermal conductivity of carbon fiber polymers. The conductivity is normally raised by 60 percent by enhancing the curing pressure from 0.1 to 2.0 MPa and almost by 35 percent by incorporation of a filler. This was reported in an experiment conducted at Composite Materials Research Laboratory at the University of Buffalo [4]. The experiments were conducted to determine the effect of curing pressure and filler incorporation on the mechanical and conductivity properties of a material. The mechanical test was conducted on a 15-lamina cross-ply composite plate under flexure using a hydraulic mechanical testing procedure. The thermal resistivity (m2 K/W) and the thermal resistance (K/W) were used to report the increase in thermal conductivity of the resultant material after this treatment. The thermal resistivity increased after a raise of the curing pressure from 0.1 to 2 MPa. This resistivity further increased after the filler incorporation [4]. This implies that the thermal conductivity of the material increased after subjecting the material to the two treatments. It was also noted that increasing curing pressure increases the through-thickness thermal conductivity more than the filler incorporation. The experiment revealed that the optimum through-thickness thermal conductivity achieved through the process was 1.5 W/m K.&nbsp.

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