Term
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Definition
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Term
| What are the 2 main types on energy thermodynamics is concerned with? |
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Definition
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Term
| What are the 2 main types of mechanical energy? |
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Definition
| Potential energy and kinetic energy. |
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Term
| What are the 2 main types of Thermal energy? |
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Definition
| Internal potential energy and internal kinetic energy. |
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Term
| What are the methods of heat transfer? |
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Definition
| convection, conduction and radiation. |
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Term
| What is Saturation Temperature/Pressure? |
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Definition
| The point at which liquid and vapor may exist in equilibrium contact with each other. |
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Term
| If something is "subcooled" what does that mean? |
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Definition
| The temperature is below it's boiling point. |
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Term
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Definition
| When heat is transferred to a liquid, the average velocity of the molecules is increased, As the average velocity of the molecules increases, some molecules at/near the surface of the liquid momentarily achieve unusually high velocities => escape from liquid and enter the vapor phase. |
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Term
| What is a saturated liquid? |
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Definition
| a liquid that is at a specified pressure AND at the saturation temperature for that particular pressure. |
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Term
| What is a saturated vapor? |
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Definition
| A vapor that is at any specified pressure AND at the saturation temperature corresponding to that pressure. |
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Term
| What is a superheated vapor? |
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Definition
| Vapor temperature is greater than saturation temperature. |
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Term
| What is a subcooled liquid? |
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Definition
| A liquid below saturation temperature for that same pressure. |
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Term
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Definition
| An indication of the internal kinetic energy contained in a substance. |
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Term
| What do you use to measure temperature? |
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Definition
| Thermometers and Pyrometers, |
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Term
| How do expansion thermometers work? |
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Definition
| They operate on the principle that expansion of a solid, liquid, or gas has a known relationship to temperature change. |
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Term
| What are the different types of expansion thermometers? |
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Definition
Liquid-in-glass,
Bimetallic expansion,
Filled systems/distant reading. |
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Term
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Definition
| Temperature measuring device suitable for use at very high temperatures. |
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Term
| What are the 2 types of pyrometers? |
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Definition
| Thermocouples, and Resistance Thermometer. |
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Term
| How does a thermocouple work? |
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Definition
| Voltage generated when two junctions of 2 dissimilar metals are at different temperatures. |
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Term
| How does a resistance thermometer work? |
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Definition
| Based on principle that electrical resistance of metal changes with changes in temperature. |
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Term
| What are some mechanical pressure measuring devices? |
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Definition
Manometer,
Bourdon Tube,
Bellows. |
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Term
| What is an electrical pressure measuring device and how does it work? |
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Definition
| A Transducer - receives energy in the form of pressure; retransmits it in the form of electrical current |
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Term
| What is the first law of thermodynamics? |
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Definition
| Energy can be neither created nor destroyed, only altered in form. |
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Term
| What is the second law of thermodynamics? |
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Definition
1-Energy will flow in only one direction -- from the high energy region to a low energy region.
2-The substance tries to reach equilibrium where all molecules are at the same energy level. 3-No heat flow w/o temp. difference AND heat flows from hot to cold. 4-No engine can convert all the heat supplied to it into mechanical work, since some heat must always be rejected to a receiver which is at a LOWER temperature than the source....No heat engine is 100% efficient. |
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Term
| What is the Carnot cycle? |
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Definition
| A completely reversible heat engine.(Theoretical) |
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Term
| What is the formula for Carnot effieciency? |
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Definition
| Source Temp. - Reciever Temp / Source Temp. and x 100% = Efficiency. |
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Term
| What temperature scale must be used in the Carnot efficency formula? |
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Definition
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Term
| What are the 5 elements of any thermodynamic cycle? |
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Definition
| Working Fluid/Substance,Heat Source, Engine, Heat receiver/heat sink, Pump. |
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Term
| What are the 4 phases of the steam cycle? |
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Definition
| Gereration, expansion, condensation and feed. |
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Term
| What are the components of the steam cycle? |
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Definition
Boiler,
Turbines (HP/LP),
Condenser,
Main condensate pump (MCP),
Main air ejector condenser,
Deaerating feed tank (DFT),
Main feed booster pump (MFBP),
Main feed pump (MFP),
Economizer. |
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Term
| What are the 8 parts of a globe valve? |
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Definition
Valve body
Packing gland/nut
Stem
Wheel/Operating mechanism,,
Disc,
Seat,
Bonnet,
Packing , |
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Term
| What are some types of valves? |
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Definition
Globe valves,
Gate valves,
Ball valves,
Butterfly valves,
Swing and Lift Check Valves,
Stop Check Valves,
Relief Valve. |
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Term
| What are some types of positive displacement pumps? |
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Definition
Rotary,
Reciprocating,
Screw. |
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Term
| What are some types of non-positive displacement pumps? |
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Definition
Centrifugal,
Jet Pumps,
Fans. |
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Term
| What is an advantage of the positive displacement pump? |
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Definition
| Roughly the same volume of fluid will leave the pump no matter what pressure the pump is discharging against. |
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Term
| What is a disadvantage of the positive displacement pump? |
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Definition
| System flow rate varies only with pump speed. CAPACITY IS PROPORTIONAL TO SPEED!!! |
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Term
| What are some advantages of a non-positive displacement pump? |
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Definition
| Can be used to pump large volumes of water, Can be placed in multiple stages to increase discharge pressure, they have numerous uses onboard ships |
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Term
| What type of fan is used in a ventilation system? |
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Definition
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Term
| What type of fan is used in boiler air feed systems and as compressors? |
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Definition
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