Mechanical power

In the industrial arena, the term power generation most typically refers to the production of electrical or mechanical power via any of several energy conversion processes. Early examples of practical power generation devices include water-wheel-powered mills for grinding grain, which were reportedly used as early as 100 BC in the Balkans and areas of the Middle East, and wind-powered mills, which were widely used as early as the tenth century in the Middle East. 

The use of wind as a renewable energy source involves the conversion of power contained in moving air masses to rotating shaft power. These air masses represent the complex circulation of winds near the surface of Earth caused by Earth s rotation and by convective heating from the sun. The actual conversion process utilizes basic aerodynamic forces, ie, lift or drag, to produce a net positive torque on a rotating shaft, resulting in the production of mechanical power, which can then be used directly or converted to electrical power. 

The ideal mechanical power requirement of a thermocompression evaporator is given by the Carnot equation ... 

Michael M Calistrat/ B S M E / M S M E / Owner, Michael Callstrat and As.sociates member, American Society of Mechanical Engineers. (Mechanical Power-Tran.smlssion Equipment)... 

Processes, other than wet processes, in which metal articles (other than gold, platinum or iridium) are ground, abraded or polished using mechanical power, in any room for more than 12 hours per week 6 months... 

The above has been isolated from all sources of electrical and mechanical power... 

A fan with a diameter of 60 cm and a speed of 100 RPM will have a heat transfer capacity of 100W/°C, needs a mechanical power of 4W, has a noise level of 40 dB(A) and costs 180 Euro. 

Effective mechanical power The energy spent in overcoming external mechanical forces on the body, in W, normally ignored for most activity. 

Burning continues as the piston reverses at TDC and pressure rises through the first portion of the power or expansion stroke. It is the increase in pressure due to burning the fuel that forces the piston to the right to produce useful mechanical power. The piston moves to the right until BDC is reached. 

Between 1935 and 1960 outputs per man-hour of labor increased about 4.5 times, and crop production per hectare of crop-land almost doubled. Inputs of labor were decreased by 50 percent, inputs of land remained relatively stable, but inputs of non-real-estate capital inputs were nearly tripled. Among these capital inputs, those of seed, feed, and livestock purchased increased by about four times, and those of mechanical power and machinery by more than 2.5 times. 

Irrigation with mechanically powered pumps substantially increases commercial energy requirements but also increases yields. (Corbis-Eettmann)... 

By the end of the nineteenth centuiy, smokejacks had evolved into the hot air turbine, which found application as aircraft turbosuperchargers before evolving into gas turbines. Some engines such as the General Electric LM2500 have a separate hot air power turbine that converts hot exhaust air into mechanical power. 

Most induction ac motors are fixed-speed. However, a large number of motor applications would benefit if the motor speed could be adjusted to match process requirements. Motor speed controls are the devices which, when properly applied, can tap most of the potential energy savings in motor systems. Motor speed controls are particularly attractive in applications where there is variable fluid flow. In many centrifugal pump, fan, and compressor applications mechanical power grows roughly with the cube of the fluid flow. To move 80 percent of the nominal flow only half of the power is required. Centrifugal loads are therefore excellent candidates for motor speed control. Other loads that may benefit from the use of motor speed controls include conveyers, traction drives, winders, machine tools and robotics. 

Stii facc-following devices use a mechanical linkage between two floating objects or between a floating and a fixed object to produce useful mechanical power. This mechanical power can either be connected directly to a generator or transferred to a working fluid, such as water or air, which drives a turbine generator. 

The principle of harnessing the energy of tides dates back to eleventh-century England when tides were used to turn waterwheels, producing mechanical power. More recently, rising and falling tides have been used to generate electricity, in much the same manner as hydroelectric power plants. 

This is a very good motor for direct connection to certain loads, particularly where constant speed is required. NEMA defines it as a synchronous machine which transforms electrical power from an alternating-current system into mechanical power. It usually has direct-current field excitation by a separately driven direct-current generator or one directly connected to the motor. This motor remains synchronous with the supply frequency and is not affected by the load. Proper application requires consideration of the following ... 

Thus from Equation 2-215 we see that for a given dynamo geometry, the developed torque only depends on the interaction between two magnetic fields and their orientation with respect to each other. One or both of the magnetic fields may be induced by a current. If one of the fields is the field of a magnet, then it may be either in the rotor or the stator. If the rotation results from the imposition of mechanical power on the rotor, the device is called a generator. If the rotation is caused by the flow of current, the device is called a motor, i.e., converts electric power to mechanical power. 

Synchronous Motor. A synchronous motor is a synchronous machine which transforms electrical power into mechanical power. 

Just as for the primary-voltage control system, the air-gap power at slip s divides between mechanical power and rotor-circuit power in the wound-rotor drive. Except... 

In nearly all mechanical power applications in the oil and gas industry it is necessary to transmit the power generated by a prime mover to an operation (e.g., drawworks of a drilling rig, or a production pumping system). The transmission of rotary power to such operation elements is carried out by a power transmission system. Mechanical power transmission is typically carried out by power betting systems, chain systems, gear systems and by hydraulic systems, or some combination of these three [1,5]. 

Greenwood, D. G., Mechanical Power Tranmissions, McGraw-Hill Book Co., New York, 1962. 

The mechanical power can be calculated with the formula when the RPM and torque are known. Both are measured downhole in Anadrill geosteering system ... 

The study of hydraulics deals with the use and characteristics of liquids and gases. Since the beginning of time, man has used fluids to ease his burden. Earliest recorded history shows that devices such as pumps and water wheels were used to generate useable mechanical power. 

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