thermal efficiency

Japanese: thermal efficiency（英語表記）thermalefficiency

…In reality, it is not possible to extract all the energy added as useful work, so the actual efficiency of a machine is less than 1. For a heat engine that converts thermal energy into mechanical work, the ratio of the useful work obtained to the heat added is called the thermal efficiency. The process of converting heat into work is restricted by the second law of thermodynamics, and it is impossible to completely convert the heat _Q1 obtained from a high-temperature heat source ( temperature T1 ) into work. In _the conversion process, _a part of the heat _Q2 must be discarded to a _low -temperature heat source (temperature T2 ), _so the thermal efficiency is ( Q1 - Q2 _)/Q1 ₌ ( _T1 - T2 )/ T1 _. …

*Some of the terminology that mentions "thermal efficiency" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…現実には，加えられたエネルギーをすべて有効な仕事として取り出すことはできないので，実際の機械の効率は1より小さい。熱エネルギーを力学的仕事に変換する熱機関については，それに加えた熱に対する得られた有効仕事の割合を熱効率thermal efficiencyと呼んでいる。熱から仕事への変換過程については，熱力学の第2法則によって制約を受け，高温の熱源(温度T₁)から得た熱Q₁を完全に仕事に変えることは不可能で，変換過程で必ず熱の一部Q₂を低温の熱源(温度T₂)に捨てなければならず，熱効率は(Q₁－Q₂)/Q₁＝(T₁－T₂)/T₁となる。…