Abstract A new efficient computational approach for the determination of the main design parameters of the parabolic trough receiver is presented. The approach is based on a classical combination of the Monte Carlo ray tracing method for the optical problem and the 3D finite volume method for the thermo-fluid problem. Unlike previous studies, modeling was carried out using a created fully dimensionless thermo-fluid mathematical model and dimensionless numerical algorithm. Criterial complexes (relations between thermophysical, dynamic and geometrical properties) act as dimensionless variables in a mathematical model. A single criterial dependency for describing the temperature fields for any receiver geometry and any heat transfer fluid type was obtained. A proposed solution is correct for any inlet and ambient temperatures. The impact of concentrator surface errors and the design of a tube receiver on temperature fields was studied as well. The present study is the first attempt to mathematically generalize the thermo-fluid analysis in the parabolic trough receiver. A user can efficiently evaluate and predict all thermo-fluid parameters for chosen parabolic trough concentrator geometry with only one dependency without using costly standard software packages. Obtained data is useful for analysis during both the design and operational stages.