What is ntu in thermodynamics?

Answer 1

NTU is nothing but Number of Transfer Units. It is one of the method used to find the heat transfer of hot and cold body it is applicable to both parallel and counter flow.

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The NTU Method is used to calculate the rate of heat transfer in heat exchangers when there is insufficient information to calculate the Log-Mean Temperature Difference (LMTD). If fluid inlet and outlet temperatures are specified or can be determined by simple energy balance, the LMTD method should be used; but when these temperatures are not available The NTU or The Effectiveness method is used. It is based off of the maximum possible heat exchange in an infinitely long heat exchanger. From this, different heat exchangers can be compared and estimates of actual heat exchange calculated based on the NTU effectiveness.

Answer 2

NTU (Number of Transfer Units) is a dimensionless parameter used to characterize the performance of heat exchangers. It is a measure of the heat transfer effectiveness in a system and is used to calculate the amount of heat transfer in a given heat exchanger design. NTU is calculated as the product of the Heat exchanger effectiveness and the ratio of the heat capacity rate of the system to the mass flow rate of the fluid.