A counter-flow heat exchanger has a heat transfer area of 2 m² and an overall heat transfer coefficient of 200 W/(m²·K). The hot fluid cools from 135 to 55 °C and the cold fluid heats from 30 to 50 °C. Find the heat transfer rate Q̇.
In a counter-flow heat exchanger the hot fluid cools from 125 to 75 °C while the cold fluid heats from 30 to 105 °C. Find the log-mean temperature difference ΔTlm.
A counter-flow heat exchanger transfers 310 kW. The hot fluid cools from 155 to 85 °C and the cold fluid heats from 10 to 75 °C. The overall heat transfer coefficient is 1500 W/(m²·K). Find the heat transfer area A needed.
In a condenser, steam condenses at a constant 100 °C on the outside of the tubes. Cooling water (0.5 kg/s, cp = 4.18 kJ/(kg·K)) flows through the tubes and heats from 20 to 50 °C. The overall heat transfer coefficient is 3500 W/(m²·K). Find the heat transfer area A needed.
Hot oil (1 kg/s, cp = 2.3 kJ/(kg·K)) cools from 145 to 125 °C in a counter-flow exchanger. It heats 0.5 kg/s of water (cp = 4.18 kJ/(kg·K)) that enters at 30 °C. With U = 500 W/(m²·K), find the heat transfer area A needed.
Hot oil (1 kg/s, cp = 2.1 kJ/(kg·K)) cools from 100 to 70 °C in a counter-flow exchanger. It heats 1.5 kg/s of water (cp = 4.18 kJ/(kg·K)) that enters at 25 °C. With U = 500 W/(m²·K), find the heat transfer area A needed.
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