# GATE Mechanical 2014 Set 3 | Question: 48

A double-pipe counter-flow heat exchanger transfers heat between two water streams. Tube side water at $19$ liter/s is heated from $10^{\circ} \: C$ to $38^{\circ} \: C$. Shell side water at $25$ $litre/s$ is entering at $46^{\circ} \: C$. Assume constant properties of water; density is $1000 \: kg/m^3$ and specific heat is $4186 \: J/kg.K$. The LM TD (in $^{\circ}C$) is _______

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