899
The experimental results show that the overall heat transfer coefficient of 35–120 W/m2 K is achievable for an air-water fluid combination for air-side flow rate of 3–24 L/s and water-side flow rate of 12.5 mL/s .
 concept or principle: experimental; concept or principle: heat transfer; material: K; material: fluid; process parameter: flow rate; process parameter: flow rate
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 concept or principle: experimental; concept or principle: heat transfer; material: K; material: fluid; process parameter: flow rate; process parameter: flow rate