Apower cycle operates between a lake’s surface water at a temperature of 25 oc and water at a depth whose temperature is 8oc. at steady state the cycle develops a power output of 12 kw, while rejecting energy by heat transfer to the lower temperature water at the rate 14,400 kj/min.

The thermal efficiency of the power cycle is 5 %.

Explanation:

Given that,

Surface temperature = 25°C

Under water temperature = 80°C

Output power = 12 kW

Rate = 14400 kJ/min = 240 kJ/sec

Suppose we need to find the thermal efficiency of the power cycle

We need to calculate the thermal efficiency

Using formula of the thermal efficiency

Where, Q₁ = heat input

We know that,

Now put the value of Q and W in to the formula of efficiency

Hence, The thermal efficiency of the power cycle is 5 %.

a cold ice-tea.

pour in room temperature or cold water. cover the pitcher and refrigerate. steep white or green tea for 6 to 8 hours; steep black or oolong tea for 8 to 12 hours.jun 28, 2015