Abstract— Opposed piston linear Compressor is considered to be future of silent, reliable and efficient compression technologies. Unlike reciprocating compressors which are driven by rotary motors and need a crank connecting rod mechanism to convert rotary into linear motion. An opposed piston linear compressor is driven by a linear motor which reduces number of moving parts. This feature makes the compressor more reliable, more efficient and silent operation. The piston (suspended on spring stiffness) in the linear compressor is a free piston i.e. motion of the piston is not constrained hence the performance of the linear compressor is highly dependent on system resonance. Free piston motion offers the unique advantage of ease of modulation …show more content…
Compressor is the heart of VCRS as it compresses the refrigerant (R134a), increasing its pressure so as to release heat further in the cycle during condensation. Until now, the reciprocating compressors were used in refrigerators. But they have their drawbacks like high rate of wear, friction, and high pressures by the piston on the cylinder walls and increasing noise level. Reciprocating compressors have high mechanical losses during conversion from rotary to linear motion using crank and connecting rod mechanism. The modern linear compressor technology offers various advantages over a reciprocating compressing machine. This is the most popular among recent compression technologies. It uses a spring-piston arrangement, driven by linear motor. Yingbai XIE et al. [1] reported that a linear compressor is a free piston-type compressor in which the linear motor drives piston, rather than by a rotary motor coupled to a conversion mechanism as in a conventional reciprocating compressor. Linear motors are simple devices in which axial forces are generated by currents in a magnetic field. Wen WANG et al. [2] mentioned that the linear motor for linear compressor should satisfy some demands, such
Ruth Schwartz Cowan wrote “How the Refrigerator Got Its Hum” in 1983. It was included in the section, “Failed Machines” of her book. I never thought about why most refrigerators are electric. We have owned gas stoves and dryers, but never a gas refrigerator. Gas appliances cost more upfront, but are inexpensive to run over time. Personally, I would rather have gas appliances than electric and believe many other people would too; however, there are major factors that caused the gas refrigerator to fail.
"Refrigerators." Canada Science and Technology Museum. Canada Science and Technology Museum, 2014. Web. 15 Feb. 2014. .
Due to compression, TV audio and video require less bandwidth and multiple digital TV channels can fit unto one satellite transponder as oppose to a single analogue channel occupying the whole transmission line.
[3] T. A. Lipo, "Recent Progress in the Development of Solid-State AC Motor Drives," pp. 105-117, 2 April 1998 .
In this time of age, things have been consuming a lot of electricity compared to the old electrical appliances. People have been innovating different types of electrical appliances to reduce the amount of electricity used by the household such as air conditioner, refrigerator, television, and other appliances. One way of saving electricity which have been introduced in the new era is the Bio Robot Refrigerator introduced by a student from Russia, Yuriy Dmitriev, which is one of the 25 finalists in the Electrolux Design Lab competition. The competition is to challenge the entrants to redesign the modern appliances for the future.
Refrigeration Refrigeration is defined as “The process of removing heat from an enclosed space, or from a substance, to lower its pressure.” (First website given in bibliography) In simpler terms, it is removing heat from states of matter in order to keep them cooler. The basic need for refrigeration is to cool food and beverages, as they often get spoilt if the temperature is high. Before actual refrigerators and other such mechanical systems were introduced, it was very common for people to cool their food with ice and snow.
Mechanical based heat pumps systems all have some common components: a compresser, a condenser, and an evaporator. The whole system is made of pipes that circulate a fluid that allows the transfer of heat. The evaporator is what transfer heat from the air in the room to the fluid inside of the system of pipes. The condenser is what takes the heat from the fluid and transfers it to the air outside.
Opercular pumping is a mechanism utilized by certain fish for gas exchange. An opercular pump is used to pump water through the gills in an almost continuous unidirectional flow (SHSU). A dual pump is used in tandem in order to drive the unidirectional flow, both a buccal cavity and opercular cavity work simultaneously. The oral valve along the buccal cavity opens, allowing an influx of water. This influx of water causes an expansion of the opercular cavity, dropping the pressure (Hall). Water then enters into the opercular cavity and flows out due to opercular cavity compression. This compression pumps water out which leaves fresh air in the buccal cavity to be brought to the lungs for respiration. Lungfish utilize a different method of
Our orthocyclically-wound motor coil makes it possible to manufacture the stator windings with the highest possible copper fill factor, allowing for a shortened motor length while increasing power output by up to 80
Over the years my family has taken numerous road trips across the country. During these trips we would pass through countless wind farms which would peak my curiosity. Therefore, I decided to do some research into wind turbines.
Is it ethical or even helpful to try to impose order on a haphazard existence? Is it right to play God, to steal the limelight from the cosmos? Man used to ponder existence, but with the increasing possibilities of science, we now ponder our power over existence. In “An Experiment with an Air Pump,” Shelagh Stephenson uses symbolism associated with Isobel as a voice of foreboding in a society “enraptured by the possibilities of science” (3). Stephenson associates Isobel with a bird, a pile of bones, and a sheep to reveal the dark side of the “light,” the scientific revolution.
... 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.
In thermodynamics Refrigeration is the major application area, in which the heat is transferred from a lower temperature region to a higher temperature region. The devices which produce refrigeration are known as Refrigerators and the cycle on which it operates are called refrigeration cycles. Vapour compression refrigeration cycle is the most regularly used refrigeration cycle in which the refrigerant is alternately vaporized and condensed and in the vapor phase it is compressed. Gas refrigeration cycle is the well-known refrigeration cycle in which cycle refrigerant remains in the gaseous phase throughout the cycle. Cascade refrigeration are the other refrigeration cycles discussed in this chapter; absorption refrigeration is the one more refrigeration cycle which is used where the refrigerant is dissolved in liquid before it is compressed. One more refrigeration in which refrigeration is produced by passing the electric current through two dissimilar materials is called as the thermoelectric refrigeration.
Furnace is an appliance used for heating or melting materials. It is mainly used in industries to achieve their products. There are many types of furnaces of them, blast furnace, electric arc furnace, induction furnace are the most used ones. Especially induction furnace is widely used in many industries mostly steel plants due to its advantages over the rest.
A steam turbine's two main parts are the cylinder and the rotor. As the steam passes through the fixed blades or nozzles it expands and its velocity increases. The high-velocity jet of steam strikes the first set of moving blades. The kinetic energy of the steam changes into mechanical energy, causing the shaft to rotate. The steam then enters the next set of fixed blades and strikes the next row of moving blades. As the steam flows through the turbine, its pressure and temperature decreases, while its volume increases. The decrease in pressure and temperature occurs as the steam transmits energy to the shaft and performs work. After passing through the last turbine stage, the steam exhausts into the condenser or process steam system. The kinetic energy of the steam changes into mechanical erringly through the impact (impulse) or reaction of the steam against the blades.