The present invention relates to Tube-Tube Heat Exchangers, TT_HE, wherein combination of bends, straight lengths, tube diameter, tube material, thermal bonding enables effective transfer of heat in multi-stream multi-phase heat transfer applications.  Variation of mass flow rate of fluid stream/s at intermediate stages in a single TTHE is possible.

In the present invention judicious use of bends and straight lengths results in significant enhancement in heat transfer due to secondary flows induced in the bends.  The secondary flows induced in bend leads to enhancement in bend as well as in straight length downstream of bend without significant increase in pressure drop and pumping power.  It optionally offers a double wall vented design eliminating problem of mixing of fluid streams in case of leakage and offers the flexibility of utilizing diverse conduit materials that are compatible with the fluids.

Prof. MV Rane, Mechanical Engineering