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Research -

Interfacial Gas Transfer and Sediment-oxygen Dynamics in Vegetated Flows

(Aug. 2017 - present)

Turbulence generated by aquatic vegetation in lakes, estuaries, and rivers can significantly alter the flow structure throughout the entire water column, affecting gas transfer mechanisms at the air-water interface, thus modifying indicators of water quality. The gas transfer process can become more complex when it comes to organic sediments in the system, which is very common in nature. Such complexities include sediment transport problems and biochemical effects from organic sediments interacting with vegetation and dissolved oxygen.

In order to study and integrate the following four main topics: flow-vegetation interactions; vegetation effects on sediment transport; sediment oxygen demand and surface gas transfer process, a series of multi-scale flume experiments with different density configurations of the array of rigid and flexible simulated plants is designed and conducted at the Ecohydraulics and Ecomorphodynamics Laboratory (EEL), in Rantoul, Illinois, US.

The project is funded by NSF Career (EAR 1753200), which is led by Dr. Rafael Tinoco at University of Illinois at Urbana-Champaign.

Related Publications and Conference Presentations:

Tseng, C. Y. and Tinoco, R. O. (2022). From Substrate to Surface: A Turbulence-based Model for Gas Transfer across Sediment-water-air Interfaces in Vegetated Streams, Water Resources Research, 58(1), 2021WR030776

Tseng, C. Y. and Tinoco, R. O. (2021). A Two-Layer Turbulence-based Model to Predict Suspended Sediment Concentration in Flows with Aquatic Vegetation, Geophysical Research Letters, 48(3), 2020GL091255

Tseng, C. Y. and Tinoco, R. O. (2020). Effects of Aquatic Vegetation on Gas Exchange Process Across Air-Water and Sediment-Water Interface, AGU Fall Meeting, San Francisco, CA, USA

Tinoco, R. O. and Tseng, C. Y. (2020). From substrate to surface: the effect of vegetation-generated turbulence on surficial gas transfer, River Flow 2020, Delft, Netherlands

Tseng, C. Y. and Tinoco, R. O. (2020). A model to predict surface gas transfer rate in streams based on turbulence production by aquatic vegetation, Advances in Water Resources, 143, 10366

Tseng, C. Y. and Tinoco, R. O. (2019). Quantifying the effect of aquatic vegetation on interfacial gas transfer in streams, AGU Fall Meeting Abstracts, San Francisco, CA, USA

Multi-fidelity Uncertainty Quantification of Hydraulic Conductivity in a Watershed
(Oct. 2019 - Mar. 2021)

Enhanced water management systems depend on the accurate estimation of hydraulic properties of subsurface formations. This is while hydraulic conductivity of geologic formations could vary significantly. Therefore using information only from widely spaced boreholes will be insufficient in characterizing subsurface aquifer properties. Hence, there is need for other sources of information to complement our hydro- geophysics understanding of a region of interest.

This project presents a numerical framework where information from different measurement sources is combined to characterize the 3-dimensional random field representing the hydraulic conductivity in Upper Sangamon Watershed in east-central Illinois under a Multi-Fidelity (MF) estimation model. Coupled with this model, a Bayesian experimental design will also be presented that is used to select the best future sampling locations. This work draws upon unique capabilities of electrical resistivity tests as well as statistical inversion.

The project is funded by Illinois Water Resources Center, which is led by Dr. Maryam Ghadiri and Dr. Hadi Meidani at University of Illinois at Urbana-Champaign.

Related Publications and Conference Presentations:

Tseng, C. Y., Ghadiri, M., Larson, T. H., Kumar, P., Meidani, H. (In review). Estimation of Hydraulic Conductivity in a Watershed Using Multi-source Data via Co-Kriging and Bayesian Experimental Design, Water Resources Research

Tseng, C. Y., Ghadiri, M., Larson, T. H., Kumar, P., Meidani, H. (2021). Bayesian experimental design coupling with multi fidelity Gaussian processes, GitHub. Repository (for code and data download)

Tseng, C. Y., Ghadiri, M., Meidani, H. (2021). Estimation of Hydraulic Conductivity in a Watershed Using Multi-source Data via Co-Kriging and Bayesian Experimental Design, AGU Fall Meeting, New Orleans, LA, USA

Ghadiri, M., Tseng, C. Y., Meidani, H. (2020). Investigation of Multi-fidelity Co-Kriging Model for Hydraulic Conductivity in Sangamon Watershed, AGU Fall Meeting, San Francisco, CA, USA

Development of the Portable Thermal Response Testing (TRT) System

(Apr. 2018 - Aug. 2019)

The thermal response test (TRT) is widely applied to determine geothermal properties, such as geothermal conductivity and geothermal resistance. The TRT works on the principle that the mean temperature change caused by heated circulating water can be measured through the ground over time. The temperature response is due to heat transfer from the heated inflow to the borehole heat exchanger. This temperature response can provide us with an extrapolated prediction of the geothermal performance.

In this project, we designed a portable TRT device with a technical report describing a comprehensive workflow for operating it based on model analysis theory. We illustrated a test case of TRT measurement at the Geothermal Research Station located at the University of Illinois Energy Farm. The purpose of the report is to help future users of the TRT device learn to use the device to conduct a basic analysis of raw data from shallow geothermal heat exchange-related projects and to apply this test in both scientific research and educational programs.

The project is funded by the Geothermal Profile Project from Illinois State Geological Survey, which is led by Dr. Yu-Feng Forrest Lin at University of Illinois at Urbana-Champaign.

Related Publications and Conference Presentations:

Lin, Y. F., Tseng, C. Y., Sargent, S. L. (2020). The portable thermal response testing device user’s manual, Technical Report, Illinois State Geological Survey, Prairie Research Institute

Non-hydrostatic Coastal Ocean Modeling of Hyperpycnal River Plumes

(Aug. 2013 - Feb. 2016)

Hyperpycnal plume is a kind of sediment-laden current moving down a slope in water, which is driven by gravity and frequently occurs in nature such as lakes, reservoirs and estuaries. It plays an important role in sediment transport and carbon circulation in nature. However, it can also cause some environmental and industrial problems. Owing to the aforementioned significance, a further understanding about the mechanisms of hyperpycnal plume is required.

By using the coastal hydrodynamic ocean model "SUNTANS", we investigated the nonhydrostatic effect and the dynamics of hyperpycnal plumes on different slopes. The result showed that the nonhydrostatic effect is important in the plunging region, which can be closely related to the change of slope and 3D flow structure.

The project was funded by Taiwan Ministry of Science and Technology (MOST) Civil, Hydraulic Engineering Program under Grant No. 103-2221-E-002-206-MY3 and Aeronautical Engineering Program under Grant No. 102-2221-E-002-069-MY3, which was led by Dr. Yi-Ju Chou at National Taiwan University.