Experimental and numerical study of the heat transfer coefficients of double pipe helically coiled heat exchanger

Abstract EN

This work introduces an experimental and numerical study of the heat transfer coefficients of double pipe helically coiled heat exchanger.

It tested for both parallel and counter flow arrangements.

Water is used as working fluid in inner tubes side and annulus tube side.

The mass flow rate has range between (0.032 - 0.0721) kg/s for cold water while hot water is kept constants at (0.0724 kg/s).

Also the range of inlet temperatures of cold and hot water are (20 - 25°C), and (40 - 70 °C), respectively.

All experiments performed at the Dean Number for annulus tubes side range of (1250 - 1700).

The study directed to focus on influencing the inlet mass flow rate of annulus tubes-side, and inlet temperatures of inner tubes-side over the effectiveness, axial temperature distribution of heat exchanger, efficiency and heat transfer coefficient.

All experimental data performed at the steady-state conditions.

The results show that the mass flow rate ratio ((m_r ) ̇) effects the axial temperature distribution of heat exchanger also, the effectiveness and efficiency decreased by increasing mass flow rate ratio.

Likewise, comparisons between numerical and experimental results have been made.

Empirical correlations between the Nusselt Number with Dean and Prandtl Numbers for the annulus tube have been found