A J- type thermocouple is used to measure thetemperature in a heating process. The length ofthe bare material is 120mm and thickness is1.5mm. Find the time constant of the bare material.уре ofThermo-MaterialK (QW/m-(kg/m3)k)IS|(J/Kg-oc)coupleJIron- Constantan468535345KKromel- Alumel358738380ITCopper- Constantan 160 8902316Cromel - Contantan338825336Nicrocil- Nisil348702376Pt(30%)Rhodium -191571856Pt(6%)RhodiumPlatinum(13%)Rodium,5516628 99- PlatinumPlatinum(10%)Rodium52.9 1674599PlatinumTime constant of the bare material is, T=

Given: Length of bare material (L) = 120 mm Thickness (t) = 1.5 mm Density (Q) = 8535 kg/m3 Specific…

Answered: A J- type thermocouple is used to…

A J- type thermocouple is used to measure the temperature in a heating process. The length of the bare material is 120mm and thickness is 1.5mm. Find the time constant of the bare material.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.22P: 1.22 In order to prevent frostbite to skiers on chair lifts, the weather report at most ski areas...

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1.22 In order to prevent frostbite to skiers on chair lifts, the weather report at most ski areas gives both an air temperature and the wind-chill temperature. The air temperature is measured with a thermometer that is not affected by the wind. However, the rate of heat loss from the skier increases with wind velocity, and the wind-chill temperature is the temperature that would result in the same rate of heat loss in still air as occurs at the measured air temperature with the existing wind. Suppose that the inner temperature of a 3-mm-thick layer of skin with a thermal conductivity of 0.35 W/m K is and the air temperature is . Under calm ambient conditions the heat transfer coefficient at the outer skin surface is about (see Table 1.4), but in a 40-mph wind it increases to . (a) If frostbite occurs when the skin temperature drops to about , do you advise the skier to wear a face mask? (b) What is the skin temperature drop due to the wind?
A K- type thermocouple is used to measure the temperature in a heating process. The length of the bare material is 100mm and thickness is 1.5mm. Find the time constant of the bare material. Турe of Thermo-Material couple K ( Q W/m- (kg/m³)| k) |(J/Kg- oc) J Iron- Constantan 46 8535 345 Kromel- Alumel 35 8738 380 T Copper- Constantan 160 8902 316 Cromel - Contantan 33 8825 336 IN Nicrocil- Nisil 34 8702 376 Pt(30%)Rhodium - B 19 15718 56 Pt(6%)Rhodium Platinum(13%)Rodium 55 16628 99 Platinum Platinum(10%)Rodium - Platinum IS 52.9 16745 99 Time constant of the bare material is, T=
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The temperature of an experimental heated enclosure is being ramped up from 80 to 450°F at the rate of 19°F/min. A thermocouple, embedded in a Thermowell for protection, is being used to monitor the oven temperature. The thermocouple has a time constant of 84 s. At t = 10 min, what is the difference between the actual temperature and the temperature indicated by the thermocouple? Final answer in whole number. Please show your complete solution and write readable.
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