Table 2 Advantages and disadvantages of different types of heat pumps Type of Heat Pump Advantages Disadvantages Vapor Recompression Proven technology with very good performance Simpler process (when compared to traditional compression) Recycle of produced vapour within the system (no need for external working fluid) Low operating cost Ease of design and operation Potential for high investment cost (although this is largely dependent on design) Potentially long payback times (unacceptable for industry deployment) Use of high grade energy (electricity / mechanical work) Possibility of leakage is a concern Vapour Compression Proven at industrial scale (mature technology) No major modifications to processes with implementation Useful with corrosive and fouling components Option to drive with mechanical energy or electrical energy Acceptable efficiencies (up to 60% of Carnot’s limit) Design dependent on the ability of the heat exchange fluid to meet stringent operational, environmental and safety
The pipe is in the form of a venturi it narrows in section and then widens again, causing the airflow to increase in speed in the narrowest part. Below the venturi is a butterfly valve called the throttle valve a rotating disc that can be turned end-on to the airflow, so as to hardly restrict the flow at all, or can be rotated so that it (almost) completely blocks the flow of air. This valve controls the flow of air through the carburetor throat and thus the quantity of air/fuel mixture the system will deliver, thereby regulating engine power and speed. The throttle is connected, usually through a cable or a mechanical linkage of rods and joints or rarely by pneumatic link, to the accelerator pedal on a car or the equivalent control on other vehicles or
Figure 1. Dynamic pressure profile inside a closed shock tube. When the diaphragm is broken in (b), rarefaction and shock waves propagate in opposite directions. In (c), the rarefaction wave reflects off the left wall, and in (d), the shock wave reflects off the right wall, resulting in a greater pressure difference. The first region (4), known as the driver section, is sealed via the diaphragm and pressurized to a controlled experimental pressure, P4.
Abstract An Air Dehumidifier can be designed and modeled working on simple principle of dehumidification of compressed air by means of collision with the number of cylinders arranged in series. This dehumidifier will not require any hygroscopic media or absorptive media such as Activated Alumina, Silica gel, Salt tablets, etc. which are used in other dehumidifiers. It does not require any refrigerant which is used in the refrigerated dehumidifier. The designed dehumidifier will be most reliable for the point of application.
They found that the overall normalized Nusselt number as well as irreversibility was strongly affected by both the location of the exit port and the aspect ratio. Singh and Sharif (2003) studied mixed convection in an air-cooled rectangular cavity with differentially heated vertical isothermal side walls having inlet and exit port. Several different placement configurations of the inlet and exit ports were investigated. The best configuration was selected by analyzing the cooling effectiveness of the cavity which suggested that injecting air through the bottom of cold wall and exiting near the top of the hot wall was more effective in heat removal. The forced and natural convection assist each other in the heat removal
A dielectric liquid is a liquid which is a poor conductor of electricity but a good supporter of an electrostatic field. At specified pressure a fluid boils isothermally (no change in temperature due to the energy supplied going into converting the state of the liquid to a vapour). A large amount of heat is absorbed during this process which is essentially isothermal. This process is taking advantage of the high heat transfer coefficient associated with boiling. Another advantage is that by immersing the electronic component in a liquid medium, the temperature throughout is uniform.
Accordingly, the turbine is sized to produce high compressor speeds at these low engine speeds. At higher engine speeds where exhaust gas flow is greater, the turbine and compressor can be over-driven, particularly in cruising or part throttle conditions. This over drive reduces engine efficiency by supplying excess airflow in the case of a diesel engine, and by opposing the actions of the throttle in a gasoline engine which is attempting to restrict gas flow to the engine. In both cases excessive exhaust manifold pressure is also created. Conventionally, a waste gate valve may be included to divert exhaust flow from passing through the turbine to reduce compressor speed.
As a consequence, air enters the opening faster than air can pass through the tube and escape at the rear. Air molecules pile up inside the tube, and as more and more are crammed in the pressure inside the tube increases. As the pressure increases it tries to push air back out through the front of the tube. Equilibrium is reached between the pressure of the inrushing air and the pressure of the air in the tube, and the supersonic shock wave at the inlet is reshaped to be flat across the inlet opening. In fact, the edges of this shock wave are typically perpendicular to the inside surface of the tube, so it is called a "normal" shock wave (normal means
Induction furnace: It is a type of furnace that consumes electricity and metal is directly heated through induction process. Its advantage is that its clean, energy efficient and its melting process is controlled as compared to other techniques of melting metal. Many modern foundries use induction furnace and now a days ferrous industries are replacing cupola furnace to this furnace to melt iron (cast iron) because of fact that first one mentioned releases dust and other polluting elements. It does not uses arc or combustion so temperature of material required to melt metal is not higher , so as an advantage no valuable alloying elements are demolished . One of the weaknesses of induction furnace is that usage in foundry cannot happen due to lack
The most important advantages of the method are: it is contactless, it doesn’t require the involvement of the person (which is important in the case of unconsciousness) and gives immediate, real-time results from the measurement. However, it has to be stressed on the fact that the infrared images show only the surface temperature of the body shell, but cannot assess the temperature distribution under the skin surface. Figure 1 presents a thermogram of a face at 21 oC, with the measurement of the inner cantus of the eye. The point measurement shows an average temperature of 36.2 oC: min temperature of 35.9 oC and max temperature of 36.4 oC (which is the highest temperature on the whole