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Nowadays, parabolic trough collectors constitute the first concentrating solar thermal technology regarding global installed power. Central receivers and Fresnel receivers appear with smaller value and commercial solar dishes power are practically negligible. Several features have driven parabolic troughs to this first position, but some disadvantages are appearing, i.e. the cost reduction is not as quick as expected, the flexible or ball joints constitute leak problems with high pressure and temperature, and simplification of the mechanical structures is quite difficult. At this point, Fresnel receivers appear as a main competitor with troughs, offering lower cost but also lower efficiency; if the reduction in cost is higher than in efficiency, or if Fresnel efficiency is improved, there are potential facts which can make this simpler technology more competitive than trough collectors. In order to improve the Fresnel capabilities, it could be useful to analyze its optical properties. One important feature of Fresnel solar fields is that receiver and concentrator are mechanically separated, providing the system of a new freedom degree in comparison with trough collectors. This degree of freedom can be used in multi-tube receivers, using the high intensity thermal flux impinging in the receiver to illuminate the tubes where the fluid has higher film coefficient (i.e. where the phase change occurs) to obtain a high thermal efficiency, and using the lower thermal flux for preheating and reheating. The idea presented in this paper is to use a multi-tube Fresnel receiver with an adequate optical system that permits tailoring the thermal flux mapping in the receiver in coherence with the convection process of the thermal fluid. In order to obtain this objective, the mass flow will undergo preheating through the peripheral tubes (where the radiation flux will be lower due to the tracking, mirrors shape and sun shape errors) and will be driven afterwards to the high intensity thermal flux, where boiling (that implies high film coefficient values) takes place. A four tube receiver configuration, according to these ideas, will have two main possibilities. The first one a one-way mass flow through the peripheral tubes (inlets to the receiver) and a second pass inside the internal tubes (outlets). The second possibility assumes the mass-flow inlet receiver through one peripheral tube and the exit at the other one, the mass flow passing consecutively through the other two tubes.