Devices for the control of flow rate and thermal conditions using two-layered thin films separated by flexible complex seals. The plates of an upper thin film are separated by a sealing assembly. The sealing assembly is composed of an elastic soft seal separating closed voids of stagnant fluid and in contact with the upper plate of the device as it is the heated plate. The lower and the upper plates of the lower thin film can be separated by an elastic soft seal. The lower and upper thin films are named as main and secondary layers, respectively. Both the upper plate of the secondary layer and the lower plate of the main layer are fixed while the intermediate plate and is free to move in the vertical direction. When the pressure or the working temperature in the secondary layer increases, the secondary layer expands causing the main layer thickness to shrink. This reduces the main layer flow rate and temperature gradients within the main layer.