Overall Heat Transfer Coefficient in Different Equipment

Overall heat transfer coefficient is the measure of the ability of a surface to transfer heat. It is the combination of the thermal conductivity of the material, the thickness of the material, and the heat transfer coefficient of the fluid.

Steam Condensers

Steam condensers are used to convert steam into liquid. In steam condensers, the overall heat transfer coefficient is lower because of the low thermal conductivity of the steam. The steam has to be cooled down to the point where it condenses into a liquid, which requires a lot of heat energy to be transferred. However, once the steam has condensed into a liquid, the overall heat transfer coefficient increases.

Feed Water Heaters

Feed water heaters are used to heat the water that is used in power plants. In feed water heaters, the overall heat transfer coefficient is higher because the water is already in a liquid state. The water just needs to be heated up to the desired temperature, which requires less heat energy to be transferred compared to steam condensers.

Alcohol Condensers

Alcohol condensers are used to convert alcohol vapor into liquid. In alcohol condensers, the overall heat transfer coefficient is lower because of the low thermal conductivity of the alcohol vapor. The alcohol has to be cooled down to the point where it condenses into a liquid, which requires a lot of heat energy to be transferred. However, once the alcohol has condensed into a liquid, the overall heat transfer coefficient increases.

Steam

Steam is a gas that is formed when water is heated to a high temperature. In steam, the overall heat transfer coefficient is lower because of the low thermal conductivity of the gas. The steam has to be cooled down to the point where it condenses into a liquid, which requires a lot of heat energy to be transferred.

Conclusion

Based on the above discussion, we can conclude that feed water heaters have the highest value of overall heat transfer coefficient compared to steam condensers, alcohol condensers, and steam. This is because the water in feed water heaters is already in a liquid state, which requires less heat energy to be transferred compared to other equipment.