Calculating Steady State Heat Transfer

In summary, To calculate the steady-state rate of heat transfer per unit length in a straight, uniform circular pipe with internal diameter of 88.43 mm and external diameter of 118.38 mm carrying hot water at 63.67 deg cel, the formula for a hollow cylinder must be used. The temperature gradient is calculated using (T1-T2)/d, where d is the difference in radius of the cylinder. Once the temperature gradient is determined, the heat transfer can be calculated using 247*3.142*0.08843*2209.015025 = 151581 Wm^-1. This method is correct for calculating the steady-state rate of heat transfer per unit length.
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A straight, uniform circular pipe of internal diameter of 88.43 mm and external diameter of 118.38 mm carries hot water at 63.67 deg cel. The pipe has a thermal conductivity of 247 Wm^-1 K^-1.

how to calculate the steady-state rate of heat transfer per unit length, in W m^-1, when the outside temperature is 30.59 deg cel.

What I have done so far:-

Temperature Gradient = (T1-T2)/d, where d is the diff in radius of cylinder = (63.67-30.59)/(0.5*(118-88.43)*0.001) = 2209.015025

So,heat transfer = 247*3.142*0.08843*2209.015025 = 151581 Wm^-1

Is the method right?
 
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What is steady state heat transfer?

Steady state heat transfer refers to the process of heat transfer where the temperature and other thermodynamic properties of a system do not change with time. This means that the system has reached a state of equilibrium, where the rate of heat transfer into the system is equal to the rate of heat transfer out of the system.

How is steady state heat transfer calculated?

Steady state heat transfer is calculated using the Fourier's law of heat conduction, which states that the rate of heat transfer is directly proportional to the temperature difference and inversely proportional to the distance over which the heat is transferred. This law can be expressed mathematically as Q = kA(T2-T1)/L, where Q is the rate of heat transfer, k is the thermal conductivity, A is the surface area, T2 and T1 are the temperatures at the two ends of the material, and L is the thickness or distance over which the heat is transferred.

What are the factors that affect steady state heat transfer?

The factors that affect steady state heat transfer are the temperature difference, thermal conductivity, surface area, and distance over which the heat is transferred. Other factors such as material properties, surface roughness, and presence of insulation can also affect heat transfer.

What are the applications of steady state heat transfer?

Steady state heat transfer is used in various applications such as designing thermal insulation systems, calculating heat loss or gain in buildings, designing heat exchangers, and determining the efficiency of heating and cooling systems. It is also used in industrial processes such as drying, refrigeration, and distillation.

How is steady state heat transfer different from transient heat transfer?

The main difference between steady state and transient heat transfer is that in steady state, the temperature and other thermodynamic properties of the system do not change with time, while in transient heat transfer, there is a change in temperature over time. Transient heat transfer occurs when the system is not in equilibrium and is still adjusting to changes in temperature. This can happen during start-up or shut-down of a system, or when there is a sudden change in external conditions.

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