An electric immersion heater, 10 mm in diameter and 300 mm long, is rated at 550 W. If the heater is horizontally positioned in a large tank of water at 20 °C, estimate its surface temperatures. Estimate the surface temperature if the heater is accidentally operated in air at 20 °C.

An electric immersion heater, 10 mm in diameter and 300 mm long, is rated at 550 W. If the heater is horizontally positioned in a large tank of water at 20 °C, estimate its surface temperatures. Estimate the surface temperature if the heater is accidentally operated in air at 20 °C.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.26P

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Question

An electric immersion heater, 10 mm in diameter and 300 mm long, is
rated at 550 W. If the heater is horizontally positioned in a large tank of
water at 20 °C, estimate its surface temperatures. Estimate the surface
temperature if the heater is accidentally operated in air at 20 °C.

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Step 1: Determine surface temperature of heater when placed in water and in air

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Step 2: Determine the surface temperature of heater when placed in water

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Step 3: Determine the surface temperature of heater when placed in air

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