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Thermal Engineering Glossary

25 essential terms — because precise language is the foundation of clear thinking in Thermal Engineering.

Showing 25 of 25 terms

A process occurring without heat transfer between the system and its surroundings.

Related:IsentropicInsulationThermodynamic Process

A device that converts water into steam by adding heat, used in Rankine cycle power plants.

Related:Rankine CycleSteamSuperheater

The thermodynamic cycle for gas turbines, consisting of compression, combustion, and expansion.

Related:Gas TurbineJet EngineCompressor

An idealized thermodynamic cycle with maximum possible efficiency between two temperature reservoirs.

Related:Reversible ProcessIsothermalAdiabatic

Simultaneous production of electricity and useful thermal energy from a single fuel source.

Related:Waste Heat RecoveryEfficiencyDistrict Heating

A device that increases the pressure of a gas or vapor by performing work on it.

Related:Brayton CycleRefrigerationPressure Ratio

A heat exchanger that removes heat from a vapor to convert it back to liquid.

Related:Rankine CycleRefrigerationPhase Change

Heat transfer through direct molecular contact within a material, governed by Fourier's law.

Related:Thermal ConductivityFourier's LawTemperature Gradient

Heat transfer by the bulk movement of a fluid, either natural (buoyancy-driven) or forced (externally driven).

Related:Newton's Law of CoolingNusselt NumberBoundary Layer

A thermodynamic property quantifying energy dispersal and the irreversibility of a process.

Related:Second LawIrreversibilityDisorder

A heat exchanger where a refrigerant absorbs heat and changes from liquid to vapor.

Related:Refrigeration CyclePhase ChangeCooling

The maximum useful work obtainable from a system interacting with its environment until equilibrium.

Related:IrreversibilityAvailable WorkSecond Law

Extended surfaces added to increase heat transfer area and enhance convective heat dissipation.

Related:Heat SinkSurface AreaConvection

The governing equation for conductive heat transfer: heat flux is proportional to the negative temperature gradient.

Related:ConductionThermal ConductivityHeat Flux

A device designed to transfer thermal energy between two or more fluids without mixing them.

Related:LMTDCounterflowShell-and-Tube

A device that transfers heat from a cold source to a hot sink using work input, functioning as a reversed refrigeration cycle.

Related:COPRefrigerationHVAC

Material with low thermal conductivity used to reduce unwanted heat transfer.

Related:Thermal ResistanceR-ValueConduction

A process occurring at constant entropy, meaning it is both adiabatic and reversible.

Related:AdiabaticReversibleEntropy

Heat absorbed or released during a phase change at constant temperature.

Related:Phase ChangeBoilingCondensation

A dimensionless number representing the ratio of convective to conductive heat transfer at a boundary.

Related:ConvectionReynolds NumberPrandtl Number

Heat transfer through electromagnetic waves, governed by the Stefan-Boltzmann law.

Related:Stefan-BoltzmannEmissivityBlackbody

The thermodynamic cycle for steam power plants involving pumping, boiling, expansion, and condensation.

Related:Steam TurbineBoilerCondenser

A working fluid in refrigeration and air-conditioning systems that undergoes phase changes to transfer heat.

Related:CFCHFCR-134a

A material property ($k$) indicating the ability to conduct heat, measured in W/m·K.

Related:Fourier's LawConductionInsulation

A rotary device that extracts energy from a fluid flow (steam, gas, or water) and converts it to mechanical work.

Related:GeneratorExpansionPower Output
Thermal Engineering Glossary - Key Terms & Definitions | PiqCue