A thick-walked tube of stainless steel [18% Cr, 8% Ni, k = 19 W/m middot degree

Question

A thick-walked tube of stainless steel [18% Cr, 8% Ni, k = 19 W/m middot degree Celsius] with 2-cm inner diameter (ID) and 4-cm outer diameter (OD) is covered with a 3-cm layer of asbestos insulation [k = 0.2 W/m middot degree Celsius]. Steam flows in the pipe at 600 degree Celsius with a convective heat transfer coefficient of 2000 W/m^2 middot degree Celsius. Surrounding may be taken at 50 degree Celsius with the outside heat transfer coefficient of 15 W/m^2 middot degree Celsius. Calculate the lost by the tube per meter of length.

Explanation / Answer

We start with the equation

Q = Ti – To / [ln(r2/r1)] / 2kAL + [ln(r3/r2)] / 2kBL

Q = 2 L ( 600 – 50) / { [ln(2/1) / 19] + [ln(5/2) / 0.2]}

Q / L = 748.33 W/m

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.