Abstract: A flow cell for monitoring accumulations of microscopic material in heat exchange systems and the like, by measuring accretion on the surfaces of a pair of plates exposed to a primary flow, includes a split housing which supports the pair of plates in closely spaced relation with an inlet and an outlet positioned to apply a primary flow between the plates, and further includes a cavity formed in each housing half with the back or opposite sides of the plates exposed to the interior of the cavity and fluid inlets and outlets leading into such cavities providing for the flow of a secondary fluid through the cavities and across the back sides of the plates for the purpose of more accurately simulating the thermal gradient conditions on the plates in a heat exchanger, and for monitoring the rate of accumulation on the plate surfaces.

Abstract: Uniform and repeatable formation of a resistance element on a substrate is achieved by spinning the coated objects which are still in a wet state while rotating them about an orthogonal axis to subject the wet indicator formulation to centrifugal forces which forces the indicator formulation into contact with the substrate.