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• 1. [Article] Drop it like it’s Hot : Combining DTS and Temperature Modeling to Evaluate Stream Restoration on the Middle Fork of the John Day River

  Temperature is a key factor for salmonid health and is an important restoration metric on the Middle Fork of the John Day River in northeast Oregon. In the past century, dredge mining, deforestation, and ...

  Citation × Citation Citation Abstract Copy Title: Drop it like it’s Hot : Combining DTS and Temperature Modeling to Evaluate Stream Restoration on the Middle Fork of the John Day River Author: Hall, Austin (Austin Garrett) Temperature is a key factor for salmonid health and is an important restoration metric on the Middle Fork of the John Day River in northeast Oregon. In the past century, dredge mining, deforestation, and overgrazing have degraded stream habitat and resulted in greater daytime stream temperatures in the region. Recent restoration efforts have focused on mitigating these anthropogenic disturbances by reestablishing floodplain connections, replanting riparian vegetation, and improving instream habitat features and sediment. To evaluate these restoration projects, the Middle Fork of the John Day River was designated as an intensively monitored watershed in 2008, setting the stage for a 10-year temperature monitoring study. Temperatures measured during the summers of 2013 and 2014 add to the wealth of high resolution distributed temperature sensing (DTS) data collected by Oregon State University and serve as the first post-restoration data for a 2012 restoration project. Utilizing these data in coordination with the model, Heat Source, temperature change from two large restoration projects was quantified. Results from the study emphasize the significance of stream area and riparian vegetation on stream temperatures on the Middle Fork. Phase 2 of the Oxbow Tailings Restoration, completed in 2012, filled over a channel used for past dredge mining activities, reducing stream surface area and restoring the bifurcated channel to its historic south path. Findings show that this project has buffered daily stream temperatures, leading to decreases in maximum and daytime temperatures and increases in nightly temperatures for early August. Maximum and afternoon temperatures were shown to decrease by 0.65 °C and 0.91 °C, respectively, while nightly temperatures increased 0.85 °C. Continuing immediately downstream of the Phase 2 project, Phase 3 is currently in its final stages of construction. Objectives of Phase 3 seek to increase stream meanders, restore vegetation, and reconnect the stream to the adjacent valley and Ruby Creek tributary. Projecting future temperatures shows that the longer, wider restored channel increases afternoon temperature by 0.53 °C. Unlike Phase 2, changes to maximum and nightly temperatures were negligable. Altering the design width and vegetation for the restored channel revealed strong linear correlations to stream temperature, providing a simple tool that can be used to estimate temperature difference for future areal and shading scenarios. Title: Drop it like it’s Hot : Combining DTS and Temperature Modeling to Evaluate Stream Restoration on the Middle Fork of the John Day River Author: Hall, Austin (Austin Garrett) Temperature is a key factor for salmonid health and is an important restoration metric on the Middle Fork of the John Day River in northeast Oregon. In the past century, dredge mining, deforestation, and overgrazing have degraded stream habitat and resulted in greater daytime stream temperatures in the region. Recent restoration efforts have focused on mitigating these anthropogenic disturbances by reestablishing floodplain connections, replanting riparian vegetation, and improving instream habitat features and sediment. To evaluate these restoration projects, the Middle Fork of the John Day River was designated as an intensively monitored watershed in 2008, setting the stage for a 10-year temperature monitoring study. Temperatures measured during the summers of 2013 and 2014 add to the wealth of high resolution distributed temperature sensing (DTS) data collected by Oregon State University and serve as the first post-restoration data for a 2012 restoration project. Utilizing these data in coordination with the model, Heat Source, temperature change from two large restoration projects was quantified. Results from the study emphasize the significance of stream area and riparian vegetation on stream temperatures on the Middle Fork. Phase 2 of the Oxbow Tailings Restoration, completed in 2012, filled over a channel used for past dredge mining activities, reducing stream surface area and restoring the bifurcated channel to its historic south path. Findings show that this project has buffered daily stream temperatures, leading to decreases in maximum and daytime temperatures and increases in nightly temperatures for early August. Maximum and afternoon temperatures were shown to decrease by 0.65 °C and 0.91 °C, respectively, while nightly temperatures increased 0.85 °C. Continuing immediately downstream of the Phase 2 project, Phase 3 is currently in its final stages of construction. Objectives of Phase 3 seek to increase stream meanders, restore vegetation, and reconnect the stream to the adjacent valley and Ruby Creek tributary. Projecting future temperatures shows that the longer, wider restored channel increases afternoon temperature by 0.53 °C. Unlike Phase 2, changes to maximum and nightly temperatures were negligable. Altering the design width and vegetation for the restored channel revealed strong linear correlations to stream temperature, providing a simple tool that can be used to estimate temperature difference for future areal and shading scenarios. Close

• 2. [Article] Temperature Evolution of Spark Kernels in Quiescent and Cross-flow Conditions

  Numerous physical and chemical processes are required for successful ignition of a flammable mixture, many of which have been well characterized. However, one aspect of the ignition process that has received ...

  Citation × Citation Citation Abstract Copy Title: Temperature Evolution of Spark Kernels in Quiescent and Cross-flow Conditions Author: Okhovat, Sebastian Numerous physical and chemical processes are required for successful ignition of a flammable mixture, many of which have been well characterized. However, one aspect of the ignition process that has received limited consideration is understanding the temperature of the spark kernel. A spark kernel is the volume of heated gas that develops after plasma formation and dissipation by an electrical discharge. Thermal measurements are critical for determining if reactions become self-sustaining and improving the validity of modeling efforts. The need for quantified kernel temperatures is extended to conditions that approach the flow fields within combustion applications, such as gas turbine engines. Based on the motivation, the focus of this work was to determine the temperature of kernels and investigate the influence a cross-flow has on the temporal temperature evolution. Representative results were compared against kernel temperatures in a quiescent environment to highlight differences between the two flow conditions. In this study, a sunken fire igniter was placed in an open loop wind tunnel and discharged into a non-reacting cross-flow. Kernel temperatures, after the plasma dissipated, were determined from radiation intensity measurements and by solving the radiation transfer equation. The temperature evolution was investigated in a quiescent environment and for a range of cross-flow velocities (5.8-15.6 m/s). For both quiescent and cross-flow conditions, kernels developed into a toroidal vortex. Surrounding air was entrained into the center of the kernel, resulting in relatively lower temperatures compared to the edges. Average peak kernel temperatures in quiescent conditions were 950 K, whereas kernels in a cross-flow approached 1250 K. The higher peak temperatures were attributed to a reduced relative velocity of the vortex caused by the interaction with the cross-flow. This resulted in decreased entrainment, particularly located at the upstream side of the kernel. Most of the temperature evolution of kernels was experienced within 1.3 ms after plasma was no longer detected; up to a 500 K difference was determined between 0.6 and 1.3 ms. Kernels beyond 1.3 ms reached a uniform temperature near 600 K and had little to no variation as radiation intensities dissipated beyond optical detection. Bifurcation of kernels was detected in one-third of all spark events for both quiescent and cross-flow conditions. The sensible energy of kernels was reported to decrease with time for all cases. Higher cross-flow velocities resulted in less sensible energy. This was attributed to a reduction in apparent kernel volume even with higher temperatures. Title: Temperature Evolution of Spark Kernels in Quiescent and Cross-flow Conditions Author: Okhovat, Sebastian Numerous physical and chemical processes are required for successful ignition of a flammable mixture, many of which have been well characterized. However, one aspect of the ignition process that has received limited consideration is understanding the temperature of the spark kernel. A spark kernel is the volume of heated gas that develops after plasma formation and dissipation by an electrical discharge. Thermal measurements are critical for determining if reactions become self-sustaining and improving the validity of modeling efforts. The need for quantified kernel temperatures is extended to conditions that approach the flow fields within combustion applications, such as gas turbine engines. Based on the motivation, the focus of this work was to determine the temperature of kernels and investigate the influence a cross-flow has on the temporal temperature evolution. Representative results were compared against kernel temperatures in a quiescent environment to highlight differences between the two flow conditions. In this study, a sunken fire igniter was placed in an open loop wind tunnel and discharged into a non-reacting cross-flow. Kernel temperatures, after the plasma dissipated, were determined from radiation intensity measurements and by solving the radiation transfer equation. The temperature evolution was investigated in a quiescent environment and for a range of cross-flow velocities (5.8-15.6 m/s). For both quiescent and cross-flow conditions, kernels developed into a toroidal vortex. Surrounding air was entrained into the center of the kernel, resulting in relatively lower temperatures compared to the edges. Average peak kernel temperatures in quiescent conditions were 950 K, whereas kernels in a cross-flow approached 1250 K. The higher peak temperatures were attributed to a reduced relative velocity of the vortex caused by the interaction with the cross-flow. This resulted in decreased entrainment, particularly located at the upstream side of the kernel. Most of the temperature evolution of kernels was experienced within 1.3 ms after plasma was no longer detected; up to a 500 K difference was determined between 0.6 and 1.3 ms. Kernels beyond 1.3 ms reached a uniform temperature near 600 K and had little to no variation as radiation intensities dissipated beyond optical detection. Bifurcation of kernels was detected in one-third of all spark events for both quiescent and cross-flow conditions. The sensible energy of kernels was reported to decrease with time for all cases. Higher cross-flow velocities resulted in less sensible energy. This was attributed to a reduction in apparent kernel volume even with higher temperatures. Close

• 3. [Article] Absorption and attenuation of visible and near-infrared light in water: dependence on temperature and salinity

  This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/ao/home.cfm. ...

  Citation × Citation Citation Abstract Copy Title: Absorption and attenuation of visible and near-infrared light in water: dependence on temperature and salinity Author: Gray, Deric, Zaneveld, J. Ronald V., Pegau, W. Scott This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/ao/home.cfm. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law. Title: Absorption and attenuation of visible and near-infrared light in water: dependence on temperature and salinity Author: Gray, Deric, Zaneveld, J. Ronald V., Pegau, W. Scott This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/ao/home.cfm. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law. Close

• 4. [Article] Isolating the effects of storm events on arctic aquatic bacteria: temperature, nutrients, and community composition as controls on bacterial productivity

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Microbiology. ...

  Citation × Citation Citation Abstract Copy Title: Isolating the effects of storm events on arctic aquatic bacteria: temperature, nutrients, and community composition as controls on bacterial productivity Author: Crump, Byron C., Adams, Heather E., Kling, George W. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Microbiology. Supporting Information can be found at: http://journal.frontiersin.org/article/10.3389/fmicb.2015.00250/full#h9. Title: Isolating the effects of storm events on arctic aquatic bacteria: temperature, nutrients, and community composition as controls on bacterial productivity Author: Crump, Byron C., Adams, Heather E., Kling, George W. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Microbiology. Supporting Information can be found at: http://journal.frontiersin.org/article/10.3389/fmicb.2015.00250/full#h9. Close

• 5. [Article] Effects of water withdrawals on macroinvertebrate emergence: Unexpected results for three holometabolous species

  This is a scanned version of a published article. The original can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291535-1467. To the best of our knowledge, one or more authors of ...

  Citation × Citation Citation Abstract Copy Title: Effects of water withdrawals on macroinvertebrate emergence: Unexpected results for three holometabolous species Author: Wooster, D., Brown, P. D., DeBano, S. J., Johnson, S. L. This is a scanned version of a published article. The original can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291535-1467. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Effects of water withdrawals on macroinvertebrate emergence: Unexpected results for three holometabolous species Author: Wooster, D., Brown, P. D., DeBano, S. J., Johnson, S. L. This is a scanned version of a published article. The original can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291535-1467. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 6. [Article] Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon Author: Chang, Heejun, Steele, Madeline, Brown, Cheryl A., Sharp, Darrin Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon Author: Chang, Heejun, Steele, Madeline, Brown, Cheryl A., Sharp, Darrin Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 7. [Article] The effects of water withdrawals on the emergence timing, adult body mass, and total emerging biomass of aquatic insects from two northeast Oregon rivers

  Small low-head diversion dams are capable of removing much of the flow of a river, often resulting in increased water temperatures and habitat loss. Warmer temperatures have been shown to accelerate aquatic ...

  Citation × Citation Citation Abstract Copy Title: The effects of water withdrawals on the emergence timing, adult body mass, and total emerging biomass of aquatic insects from two northeast Oregon rivers Author: Brown, Phil D. Small low-head diversion dams are capable of removing much of the flow of a river, often resulting in increased water temperatures and habitat loss. Warmer temperatures have been shown to accelerate aquatic invertebrate growth and development, and discharge reductions can reduce instream habitat, suggesting that water withdrawals may alter both the timing of aquatic insect emergence and the total emerging biomass from a river. To examine the influence of water withdrawals on the timing and magnitude of aquatic insect emergence, we monitored emergence continuously for 9-10 weeks during the summer of 2006 on the Umatilla and Walla Walla rivers of northeastern Oregon. Multiple sample sites were located along gradients of decreasing discharge and increasing water temperatures caused by successive diversions on each river. The emergence timing and adult body size of three holometabolous species (Helicopsyche borealis, Petrophila confusalis, and Glossosoma traviatum) were compared to discharge, water temperature, and other physical habitat variables. The emergence timing of entire taxonomic families was also compared to these variables, and the total emerging biomass was estimated for each site. Despite reductions in discharge of up to 93% and increases in average water temperature of up to 4.6°C from upstream to downstream, emergence timing was unaltered for H. borealis, P. confusalis, and G. traviatum. However, in a laboratory experiment, higher temperatures led to earlier emergence for H. borealis. With the exception of Hydroptilidae, emergence timing was not correlated with discharge or water temperature for all 8 taxonomic families on each river, and the timing of total emergence remained similar among sites. Similarly, water temperature was not significantly correlated with reduced adult body size of these species, though female P. confusalis were 31% smaller at the warmest sample site. Total emerging biomass was reduced at sites subject to high water withdrawals, particularly on the more heavily diverted Umatilla River. The holometabolous life histories of the three tested species and the occurrence of water withdrawals for decades prior to this study are possible explanations for the observed lack of response to seasonal alterations in discharge and water temperature. These results suggest that the life histories of some aquatic invertebrates in Western rivers may be resistant to severe water withdrawals, but important ecological effects may exist through the reduced export of emerging biomass into the riparian ecosystem. Title: The effects of water withdrawals on the emergence timing, adult body mass, and total emerging biomass of aquatic insects from two northeast Oregon rivers Author: Brown, Phil D. Small low-head diversion dams are capable of removing much of the flow of a river, often resulting in increased water temperatures and habitat loss. Warmer temperatures have been shown to accelerate aquatic invertebrate growth and development, and discharge reductions can reduce instream habitat, suggesting that water withdrawals may alter both the timing of aquatic insect emergence and the total emerging biomass from a river. To examine the influence of water withdrawals on the timing and magnitude of aquatic insect emergence, we monitored emergence continuously for 9-10 weeks during the summer of 2006 on the Umatilla and Walla Walla rivers of northeastern Oregon. Multiple sample sites were located along gradients of decreasing discharge and increasing water temperatures caused by successive diversions on each river. The emergence timing and adult body size of three holometabolous species (Helicopsyche borealis, Petrophila confusalis, and Glossosoma traviatum) were compared to discharge, water temperature, and other physical habitat variables. The emergence timing of entire taxonomic families was also compared to these variables, and the total emerging biomass was estimated for each site. Despite reductions in discharge of up to 93% and increases in average water temperature of up to 4.6°C from upstream to downstream, emergence timing was unaltered for H. borealis, P. confusalis, and G. traviatum. However, in a laboratory experiment, higher temperatures led to earlier emergence for H. borealis. With the exception of Hydroptilidae, emergence timing was not correlated with discharge or water temperature for all 8 taxonomic families on each river, and the timing of total emergence remained similar among sites. Similarly, water temperature was not significantly correlated with reduced adult body size of these species, though female P. confusalis were 31% smaller at the warmest sample site. Total emerging biomass was reduced at sites subject to high water withdrawals, particularly on the more heavily diverted Umatilla River. The holometabolous life histories of the three tested species and the occurrence of water withdrawals for decades prior to this study are possible explanations for the observed lack of response to seasonal alterations in discharge and water temperature. These results suggest that the life histories of some aquatic invertebrates in Western rivers may be resistant to severe water withdrawals, but important ecological effects may exist through the reduced export of emerging biomass into the riparian ecosystem. Close

• 8. [Article] Calibrating Single-Ended Fiber-Optic Raman Spectra Distributed Temperature Sensing Data

  This is the publisher’s final pdf. The published article is copyrighted by the Multidisciplinary Digital Publishing Institute and can be found at: http://www.mdpi.com/journal/sensors.

  Citation × Citation Citation Abstract Copy Title: Calibrating Single-Ended Fiber-Optic Raman Spectra Distributed Temperature Sensing Data Author: Hausner, Mark B., van de Giesen, Nick, Selker, John S., Tyler, Scott W., Glander, Kenneth E., Suarez, Francisco This is the publisher’s final pdf. The published article is copyrighted by the Multidisciplinary Digital Publishing Institute and can be found at: http://www.mdpi.com/journal/sensors. Title: Calibrating Single-Ended Fiber-Optic Raman Spectra Distributed Temperature Sensing Data Author: Hausner, Mark B., van de Giesen, Nick, Selker, John S., Tyler, Scott W., Glander, Kenneth E., Suarez, Francisco This is the publisher’s final pdf. The published article is copyrighted by the Multidisciplinary Digital Publishing Institute and can be found at: http://www.mdpi.com/journal/sensors. Close

• 9. [Article] Potential effects of climate change on Plethodon shermani

  Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system ...

  Citation × Citation Citation Abstract Copy Title: Potential effects of climate change on Plethodon shermani Author: Ennis, Kelli N. Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system induced from temperature changes, which may affect the ability of P. shermani to rely on external cues for mating season. The courtship rituals of P. shermani have been well-documented; deviations from the expected patterning of behavior was measured via both initiation of and length of time spent in the “tail straddle walk” in addition to insemination success rate. It has been determined that an increase in temperature has implications in more inseminations, while the reverse is apparent for decreased temperature; indicating that climatic changes may lead to an earlier breeding season with warmer temperatures. The effects on our sampling may translate either directly or indirectly to the population, community, and other amphibian-containing ecosystems. We suggest further research that may aid our ability to predict the capacity for amphibians to adjust to climatic changes. Title: Potential effects of climate change on Plethodon shermani Author: Ennis, Kelli N. Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system induced from temperature changes, which may affect the ability of P. shermani to rely on external cues for mating season. The courtship rituals of P. shermani have been well-documented; deviations from the expected patterning of behavior was measured via both initiation of and length of time spent in the “tail straddle walk” in addition to insemination success rate. It has been determined that an increase in temperature has implications in more inseminations, while the reverse is apparent for decreased temperature; indicating that climatic changes may lead to an earlier breeding season with warmer temperatures. The effects on our sampling may translate either directly or indirectly to the population, community, and other amphibian-containing ecosystems. We suggest further research that may aid our ability to predict the capacity for amphibians to adjust to climatic changes. Close

• 10. [Article] Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature

  Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential ...

  Citation × Citation Citation Abstract Copy Title: Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature Author: Pratte, William Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential to improve efficiencies for combining concentrated solar power with supercritical CO2 Brayton cycles, where structures operate at high temperatures (760 ˚C) and high pressures (25 MPa). This work uses computational modeling to provide a design space for microchannel geometries under these conditions by using a Representative Volume Element approach. Additionally, low cycle fatigue results are used to develop a Manson-Coffin relation to predict the effects of plastic loading on the fatigue life of diffusion bonded specimens. Manson-Coffin relations at temperatures of both 760 ˚C and room temperature had respective R2 values of 0.9406 and 0.676, indicating reasonable reliability in results. Title: Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature Author: Pratte, William Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential to improve efficiencies for combining concentrated solar power with supercritical CO2 Brayton cycles, where structures operate at high temperatures (760 ˚C) and high pressures (25 MPa). This work uses computational modeling to provide a design space for microchannel geometries under these conditions by using a Representative Volume Element approach. Additionally, low cycle fatigue results are used to develop a Manson-Coffin relation to predict the effects of plastic loading on the fatigue life of diffusion bonded specimens. Manson-Coffin relations at temperatures of both 760 ˚C and room temperature had respective R2 values of 0.9406 and 0.676, indicating reasonable reliability in results. Close