A heat exchanger , comprising: a first manifold defining a first fluid inlet ; a second manifold defining a second fluid inlet ; and a lattice cell body having: a first set of flow passages in fluid communication with the first manifold , and where the first set of flow passages include a set of first furcated flow passages extending from the first fluid inlet ; and a second set of flow passages in fluid communication with the second manifold , and where the second set of flow passages include a set of second furcated flow passages extending from the second fluid inlet , wherein at least a portion of the first furcated flow passages are intertwined with at least a portion of the second furcated flow passages ; characterized in that : the set of first furcated flow passages converge to a first interconnecting passage that forms a hyperbolic shape and diverges into another set of first furcated flow passages , wherein the convergence to and the divergence from the first interconnecting passage of the said sets of first furcated flow passages defines a first saddle point ; and the set of second furcated flow passages converge to a second interconnecting passage that forms a hyperbolic shape and diverges into another set of second furcated flow passages . a first manifold defining a first fluid inlet ; a second manifold defining a second fluid inlet ; and a lattice cell body having: a first set of flow passages in fluid communication with the first manifold , and where the first set of flow passages include a set of first furcated flow passages extending from the first fluid inlet ; and a second set of flow passages in fluid communication with the second manifold , and where the second set of flow passages include a set of second furcated flow passages extending from the second fluid inlet , a first set of flow passages in fluid communication with the first manifold , and where the first set of flow passages include a set of first furcated flow passages extending from the first fluid inlet ; and a second set of flow passages in fluid communication with the second manifold , and where the second set of flow passages include a set of second furcated flow passages extending from the second fluid inlet , wherein at least a portion of the first furcated flow passages are intertwined with at least a portion of the second furcated flow passages ; characterized in that : the set of first furcated flow passages converge to a first interconnecting passage that forms a hyperbolic shape and diverges into another set of first furcated flow passages , wherein the convergence to and the divergence from the first interconnecting passage of the said sets of first furcated flow passages defines a first saddle point ; and the set of second furcated flow passages converge to a second interconnecting passage that forms a hyperbolic shape and diverges into another set of second furcated flow passages . the set of first furcated flow passages converge to a first interconnecting passage that forms a hyperbolic shape and diverges into another set of first furcated flow passages , wherein the convergence to and the divergence from the first interconnecting passage of the said sets of first furcated flow passages defines a first saddle point ; and the set of second furcated flow passages converge to a second interconnecting passage that forms a hyperbolic shape and diverges into another set of second furcated flow passages . <EOS>