Machine Parts

Difference between n-type and p-type material is given bellow:                n-type            p-type n-type   material contains a trace of an element with one or more electron. p-type material is formed by adding trace of an element that contains one fewer electron.  This type of material layer is relatively thicker. This type of material layer is especially very thin. n-type material contain excess electrons. p-type material contains excess holes.     Figure:     p-type  and n -type material

Limitations of photovoltaic cell: The limitation of photovoltaic cell is given bellow: 1.       Efficiency is low about 20 percent. 2.       Material cost is high because photovoltaic cell used all pure material. 3.       Photovoltaic cell may not operate isothermally if so Carnot principle, efficiency limitation must be considered.  4.       Cell material absorb incident ray. 5.       Internal Ohomic resistance in external current and to the shunt. 

Definition of Magneto hydrodynamic generator (MHD): Magneto hydrodynamic generator (MHD) is a process for producing electricity by passing an ionized gas through a channel across which exists a magnetic field.                                                                        Figure: Schematic Diagram of a MHD Generator Working Principle of MHD: In a conventional generator a conductor is moved against a regarding force and this requires work input. MHD is an analogous to conventional generator but a conducting fluid instead of conductor is moved through a magnetic field than a current is induced in the fluid. The fluid becomes ionized gas. When a ionized gas passed through a magnetic field some of the electrons in the ionized gas are diverted to one of the two electrode as shown above the figure.   

The difference between steam turbine and reciprocating engine is given bellow: Steam Turbine Reciprocating Engine In steam turbine working fluid is steam. In reciprocating engine working fluid is fossil fuel. Steam turbine efficiency is high and it is more than 60 %. Reciprocating engine efficiency is low and it is 30 to 40 %. Steam turbine vibration is low. But reciprocating engine vibration is high. Steam turbine has proper balancing. Reciprocating engine is unbalance or weak balance. Steam turbine lubrication is negligible. Reciprocating engine lubrication is major. Steam turbine design is simple. Reciprocating engine complex and compact. It is design for high power output. It is design for low power output. Steam turbine generates uniform power. Reciprocating engine do no