Resistive wire and temperature

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The discussion revolves around the heating characteristics of nichrome resistance wire when wrapped inside a cylinder, questioning whether a current higher than 3.61 ohms is needed to reach 650°C. It also seeks to estimate the heat transfer coefficient for a vertical cylinder at 1000°C, wondering if typical values of 5-100 W/m²K are applicable at this elevated temperature. Participants note that material properties can influence free air convection, alongside geometric factors. The conversation emphasizes the need for accurate calculations and considerations of thermal properties in high-temperature scenarios. Understanding these dynamics is crucial for effective thermal management in practical applications.
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so i have a piece of nichrome resistance wire, 230 v supply

in free air horizontal it is 650 c when current 3.61 ohm pass through.
( it in wikipedia)

if i wrap the wire around inside a concerte or metal(assum it will not conduct electricity) small cylinder say 5cm dia. does the current have to be higher that 3.61 for the cylinder to be 650 c?also is there anyway to estimate a vertical cylinder of diameter 5 and hight 3 cm? and at 1000 degree c. what would be heat transfer coefficient? for example some typical value 5-100 W/m^2 K.
but my temperature 1000 c, so i don't know if i can use 5-100 W/m^2 K or it will be much higher

(Edit:sorry don't know why part of it go cut off)
 
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did you want to finish your question?
 
also does material properties effect free air convection? or only geometry?
 
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