Engineering English
Isentropic Efficiency
Mechanical Engineering · Aerospace Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: Isentropic efficiency is the ratio of the actual work output or input of a device to the work that would be produced or required if the process were reversible and adiabatic. It quantifies how closely a real compressor, turbine, or nozzle approaches the ideal isentropic process.
Example in context
“The turbine's isentropic efficiency dropped to 78% after blade fouling, reducing overall cycle performance.”
“Türbinin izentropik verimi kanat kirlenmesinden sonra %78'e düştü ve genel çevrim performansını azalttı.”
Where engineers use it
Isentropic efficiency is used to evaluate compressors, turbines, and nozzles in power plants, refrigeration cycles, and gas turbines. Engineers apply it during performance testing and design optimization to compare actual device behavior against the ideal isentropic process, guiding improvements in efficiency and diagnosis of off-design conditions.
Synonyms: adiabatic efficiency
In Aerospace Engineering
A measure of how closely a real compressor, turbine, or nozzle approaches an ideal isentropic process. It is defined as the ratio of actual work transfer to the ideal work transfer for the same pressure ratio.
“We improved the compressor isentropic efficiency by five percentage points through blade profile redesign.”
Practice: can you use “Isentropic Efficiency” at work?
A gas turbine power plant reports a 5% drop in output. The technician provides temperature and pressure readings at the compressor and turbine. You must compute the isentropic efficiency of each component to identify the main source of degradation.
Show a model answer
“Can you calculate the isentropic efficiency of this turbine stage from the measured inlet and exit conditions?”
“Isentropic Efficiency” in 21 languages
| English | Isentropic Efficiency |
|---|---|
| Turkish | izentropik verim |
| French | rendement isentropique |
| German | isentroper Wirkungsgrad |
| Spanish | eficiencia isentrópica |
| Chinese | 等熵效率 |
| Arabic | الكفاءة الأيزنتروبية |
| Portuguese | eficiência isentrópica |
| Russian | изоэнтропийный КПД |
| Japanese | 等エントロピー効率 |
| Italian | rendimento isentropico |
| Vietnamese | hiệu suất đẳng entropy |
| Hindi | समऐन्ट्रॉपिक दक्षता |
| Thai | ประสิทธิภาพไอเซนโทรปิก |
| Indonesian | efisiensi isentropik |
| Korean | 등엔트로피 효율 |
| Bengali | আইসেনট্রপিক কার্যক্ষমতা |
| Dutch | isentropisch rendement |
| Swedish | isentropisk verkningsgrad |
| Finnish | isentrooppinen hyötysuhde |
| Ukrainian | ізоентропічний ККД |
Frequently asked questions
What does Isentropic Efficiency mean in engineering?
Isentropic efficiency is the ratio of the actual work output or input of a device to the work that would be produced or required if the process were reversible and adiabatic. It quantifies how closely a real compressor, turbine, or nozzle approaches the ideal isentropic process. In Mechanical Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce Isentropic Efficiency?
Isentropic Efficiency is pronounced /aɪsɛnˈtrɒpɪk ɪˈfɪʃənsi/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is Isentropic Efficiency used in a sentence?
Example from an engineering context: “The turbine's isentropic efficiency dropped to 78% after blade fouling, reducing overall cycle performance.”
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