A plate heat exchanger comprising a plurality of plates having a plane peripheral zone, an inner zone having sinusoidal undulations and two chimneys positioned at two opposite corners of the plates. Modules are formed by assembling two plates that make contact via the undulation troughs and the peripheral zones. The modules are stacked so as to make contact via the inlet and outlet chimneys. Each module may thus deform independently, in particular at the undulation troughs and ridges without transmitting stress to the other modules of the heat exchanger. In addition, the heat exchanger may comprise a tie rod in each inlet and outlet pipe so as to withstand the static pressure of the fluids flowing in the pipes.
