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A rearrangement of the Huggins equation is introduced which allows precise estimation from any experiment.

The result is that when dilution series experiments are analyzed, the estimates are ordinarily poorer the more dilutions are made. It is shown that when this method is used, the error structure is distorted by the presence of concentration in the quotient. Intrinsic viscosities of polymers are most often estimated using the Huggins equation, which relates the quotient ηsp/c to intrinsic viscosity and concentration c. Our study shows that ML techniques might provide deceptively high accuracy for small data sets, unless due diligence is done to avoid a high-variance model.Statistical study of the application of the huggins equation to measure intrinsic viscosity Statistical study of the application of the huggins equation to measure intrinsic viscosity We present a simple water viscosity model for a broad brine salinity and temperature range. Moreover, our study includes the recently common polymer SAV-10 that was not previously studied. We provide a predictive bulk rheology model that enables the user to accurately predict polymer viscosity without laboratory measurements and for a wide range of temperatures and brine compositions. This is the first study that comprehensively benchmarks polymer rheology models and proposes a simple, least number of coefficients, and tunable polymer-rheology model. We then investigated ML as a predictive tool without compromising overfitting the data using the simplest ML model (linear regression) all the way to artificial neural network (ANN) and hybrid ML models. We used the published models’ coefficients and then tuned their coefficients for our data set for a fair comparison. We benchmarked the bulk rheological model with existing models in the literature. Our regression boundaries obey flexible polymers’ physical and laboratory behavior. The data were preprocessed through data analytics techniques, and a model was developed with some physics basis by fitting Martin’s equation for Carreau model coefficients. We cover a broad range of polymer concentrations, temperature, salinity, and hardness with an upper limit of 5,000 ppm, 120℃, 290,000 ppm, and 33,000 ppm, respectively. This study benchmarks the existing polymer empirical and machine learning (ML) models against a new data-driven model with some physics basis for common synthetic polymers. There are existing empirical models to estimate polymer bulk rheology without prior laboratory work however, they have many coefficients, simple brine composition, and lack physics-based regression boundaries. Estimating polymer viscosity for given reservoir conditions (i.e., oil viscosity, temperature, and brine composition) requires intensive laboratory work. Polymer flooding is a common enhanced oil recovery (EOR) method used to increase aqueous phase sweep efficiency by increasing viscosity.