Energy and Heat Transfer Concepts

The amount of heat needed to raise the temperature of 1 gram of water by 1 degree Celsius.

The amount of heat needed to raise the temperature of 1 pound of water by 1 degree Fahrenheit.

The SI unit for all forms of energy, including heat.

The amount of heat needed to raise the temperature of 1 gram of a substance by 1°C.

The total amount of heat needed to raise the temperature of a given mass of a substance by 1°C.

The degree of heat possessed by a substance.

When a substance transitions from solid to liquid or liquid to gas due to heat.

Water's specific heat; it takes 1 calorie to raise 1 gram of water by 1°C.

A temperature scale where water freezes at 0°C and boils at 100°C.

A temperature scale where water freezes at 32°F and boils at 212°F.

An absolute temperature scale where 0K represents absolute zero, the lowest possible temperature.

An absolute temperature scale based on Fahrenheit, where 0°R represents absolute zero.

To convert Celsius to Kelvin, add 273 to the Celsius temperature.

To convert Fahrenheit to Rankine, add 460 to the Fahrenheit temperature.

To convert Kelvin to Rankine, multiply the Kelvin temperature by 9/5.

A device that moves heat from a cooler area to a warmer area, using a refrigerant cycle.

It uses a refrigerant to absorb heat from a cool source (like the outside air), then compresses the refrigerant to raise its temperature, and releases the heat into a warmer area (like your house).

The volume of a gas is inversely proportional to its pressure, at constant temperature.

A process that takes place at constant temperature.

V1/P1 = V2/P2, where V is volume and P is pressure.

The volume of a gas is directly proportional to its temperature, at constant pressure.

V1/T1 = V2/T2, where V is volume and T is temperature.

It does useful work by transmitting forces and utilizing thermal energy.

When the volume of a gas is kept constant, the pressure of the gas is directly proportional to its absolute temperature. This means if the temperature increases, the pressure increases proportionally, and vice versa.

A process where heat is neither gained nor lost from the system. Temperature changes occur due to internal changes in pressure or volume.

A combination of Boyle's and Charles' laws, describing the relationship between pressure (P), volume (V), and absolute temperature (T) of an ideal gas.

Energy cannot be created or destroyed, only transformed from one form to another. This applies to heat energy, which can be converted into other forms like mechanical energy.

Heat naturally flows from a warmer body to a colder body. It cannot spontaneously flow in the opposite direction.

The heat energy released when a fuel burns. This energy can be used for various applications, but some is always lost as waste heat.

In a constant volume system, pressure and temperature are directly proportional. This means as temperature increases, pressure increases proportionally, and vice versa.

Examples of adiabatic processes include the rapid expansion of a gas, leading to cooling, and the increase in cylinder temperature during rapid filling.

The process of removing excess heat from a system, like an engine, to prevent overheating and damage.

A process of reducing engine temperature by circulating a coolant, typically water, through the engine and then cooling it in a radiator.

An engine that uses the expansion of hot gases to drive turbines, generating power and producing thrust, as in jet engines.

The energy produced when expanding gases push against a force, like propelling a bullet out of a gun barrel or driving a gas turbine.

The equation W = Fs, where W is work, F is force, and s is the distance over which the force acts.

Power is the rate of doing work, calculated by dividing the work done by the time it takes.

Reducing the space between gas molecules by squeezing them, decreasing the free space for their movement.

A theoretical thermodynamic cycle representing the ideal efficiency of a heat engine, often used as a benchmark for real engines.

The process of squeezing air or a mixture of air and fuel into a smaller volume, leading to a significant increase in temperature.

Compression increases the air's temperature, making it easier to ignite the fuel and release more energy for power.

A four-stroke cycle in piston engines, where intake, compression, power, and exhaust occur sequentially.

The compressed mixture ignites, expanding rapidly and pushing the piston down, creating power.

An engine where combustion occurs at approximately constant volume, like the typical piston engine.

The cycle used in gas turbine engines, involving intake, compression, power generation, and exhaust.

Compressed air and fuel are ignited, and the expanding hot gas rotates the turbine, which powers the compressor and other components.

To increase the number of power strokes per revolution, generating more power and smoother operation.