Application and Exploration of FLUENT Software in the Teaching of Engineering Thermophysics

Engineering thermophysics is a basic discipline for energy majors, but this course emphasizes the theoretical level and is difficult to understand. Students\u27 enthusiasm and participation in the learning process are low, and it is difficult to understand the course. Accordingly, the research team attempts to introduce Fluent software into the course teaching exploration. Specifically, Fluent software is adopted to provide a reliable physics teaching model, and to change the traditional teaching mode, so as to improve students\u27 daily learning ability and practical ability, and ultimately enable students to learn and practice

Data Associated with "Logjam Characteristics as Drivers of Transient Storage in Headwater Streams"

This repository contains data for the experimental flume and numerical model runs referenced in Marshall et al., 2022. Source code, data csv files for statistical analysis, and calculated temporal moments are included.Logjams in a stream create backwater conditions and locally force water to flow through the streambed, creating zones of transient storage within the surface and subsurface of a stream. We investigate the relative importance of logjam distribution density, logjam permeability, and discharge on transient storage in a simplified experimental channel. We use physical flume experiments in which we inject a salt tracer, monitor fluid conductivity breakthrough curves in surface water, and use breakthrough-curve skew to characterize transient storage. We then develop numerical models in HydroGeoSphere to reveal flow paths through the subsurface (or hyporheic zone) that contribute to some of the longest transient-storage timescales. In both the flume and numerical model, we observe an increase in backwater and hyporheic exchange at logjams. Observed complexities in transient storage behavior may depend largely on surface water flow in the backwater zone. As expected, multiple successive logjams provide more pervasive hyporheic exchange by distributing the head drop at each jam, leading to distributed but shallow flow paths. Decreasing the permeability of a logjam or increasing the discharge both facilitate more surface water storage and elevate the surface water level upstream of a logjam, thus increasing hyporheic exchange. Multiple logjams with low permeability result in the greatest magnitude of transient storage, suggesting that this configuration maximizes solute retention in backwater zones, while hyporheic exchange rates also increase. Understanding how logjam characteristics affect solute transport through both the channel and hyporheic zone has important management implications for rivers in forested, or historically forested, environments.This research was supported by National Science Foundation Hydrologic Sciences (award 1819068)

A programmable-gain amplifier and an active inductor for in-vehicle power line communications

In-vehicle power-line communication (VPLC) is a communication technique that uses the power lines of the vehicle for data transmission. Based on the measurements of the power line communication channel, the channel response is characterized as frequency selective, time and location dependent with high signal attenuation. Also, the access impedance changes a lot in different frequency ranges. These properties impose design challenges at both system level and circuit levels of a VPLC system. This thesis presents the design of two critical building blocks of a VPLC system, namely, a variable gain amplifier (VGA) and an active inductor. VGAs are used to amplify the signal to a predefined level without introducing too much distortion. The presented VGA design targets a 0.13μm CMOS technology. The VGA design is discussed in detail. Gm-boosting technique is used to both increases the linearity and provide a programmable 0 dB to 60 dB gain over a broadband. Furthermore, the gain is stable over a wide range of temperatures. The circuit is fabricated and tested, and the measured results are in good agreement with the simulation results. Inductors are commonly used in impedance matching networks. In this work, an active inductor circuit is designed which provides a wide tuning range for VPLC LC matching networks. Active inductor is a good candidate to replace the passive inductor in the LC matching network since it has a smaller area, wider tuning range, and a higher quality-factor. The designed active inductor is a fully differential grounded Gyrator-C active inductor. Simulation results confirm that the inductor has wide tuning range with linear tuning ability; however, its bandwidth is limited. The circuit design for this VPLC system is challenging, the preliminary results of the proposed circuits show some promise; however, further work is still needed to improve the performance.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat

Treatment of Preserved Wastewater with UASB

The preserved wastewater was treated by the upflow anaerobic sludge blanket (UASB) reactor, the effects of the anaerobic time on COD, turbidity, pH, conductivity, SS, absorbance, and decolorization rate of the preserved wastewater were investigated. The results showed that with the increase of the anaerobic time, the treatment effect of the UASB reactor on the preserved wastewater was improved. Under the optimum anaerobic time condition, the COD removal rate, turbidity removal rate, pH, conductivity, SS removal rate, absorbance, and decoloration rate of the wastewater were 49.6%, 38.5%, 5.68, 0.518×104, 24%, 0.598, and 32.4%, respectively. Therefore, the UASB reactor can be used as a pretreatment for the preserved wastewater, in order to reduce the difficulty of subsequent aerobic treatment

Treatment of Preserved Wastewater with UASB

The preserved wastewater was treated by the upflow anaerobic sludge blanket (UASB) reactor, the effects of the anaerobic time on COD, turbidity, pH, conductivity, SS, absorbance, and decolorization rate of the preserved wastewater were investigated. The results showed that with the increase of the anaerobic time, the treatment effect of the UASB reactor on the preserved wastewater was improved. Under the optimum anaerobic time condition, the COD removal rate, turbidity removal rate, pH, conductivity, SS removal rate, absorbance, and decoloration rate of the wastewater were 49.6%, 38.5%, 5.68, 0.518×104, 24%, 0.598, and 32.4%, respectively. Therefore, the UASB reactor can be used as a pretreatment for the preserved wastewater, in order to reduce the difficulty of subsequent aerobic treatment

Tertiary Treatment Process of Preserved Wastewater

The effects of the composite coagulants on coagulation sedimentation for the preserved wastewater was investigated by changing the composite coagulant dosages, and the coagulant was composed of polymeric ferric sulfate (PFS), polyaluminium chloride (PAC), and polyaluminum ferric silicate (PAFSC), while the effect of the tertiary treatment process on the preserved wastewater was tested, which was exceeded the standard seriously. The results showed that 400 mg/L was the optimum composite coagulant dosage. The removal rates of salt and sugar were as high as 99.1% and 99.5% respectively, and the removal rates of CODCr and SS were 99.3% and 96.0%, respectively after the preserved wastewater was treated by the tertiary treatment technology, which both reached the primary standard of “The Integrated Wastewater Discharge Standard” (GB8978-1996)

Tertiary Treatment Process of Preserved Wastewater

The effects of the composite coagulants on coagulation sedimentation for the preserved wastewater was investigated by changing the composite coagulant dosages, and the coagulant was composed of polymeric ferric sulfate (PFS), polyaluminium chloride (PAC), and polyaluminum ferric silicate (PAFSC), while the effect of the tertiary treatment process on the preserved wastewater was tested, which was exceeded the standard seriously. The results showed that 400 mg/L was the optimum composite coagulant dosage. The removal rates of salt and sugar were as high as 99.1% and 99.5% respectively, and the removal rates of CODCr and SS were 99.3% and 96.0%, respectively after the preserved wastewater was treated by the tertiary treatment technology, which both reached the primary standard of “The Integrated Wastewater Discharge Standard” (GB8978-1996)

Recent advances in photocatalytic renewable energy production

The development of green and renewable energy is becoming increasingly more important in reducing environmental pollution and controlling CO2 discharge. Photocatalysis can be utilized to directly convert solar energy into chemical energy to achieve both the conversion and storage of solar energy. On this basis, photocatalysis is considered to be a prospective technology to resolve the current issues of energy supply and environmental pollution. Recently, several significant achievements in semiconductor-based photocatalytic renewable energy production have been reported. This review presents the recent advances in photocatalytic renewable energy production over the last three years by summarizing the typical and significant semiconductor-based and semiconductor-like photocatalysts for H2 production, CO2 conversion and H2O2 production. These reactions demonstrate how the basic principles of photocatalysis can be exploited for renewable energy production. Finally, we conclude our review of photocatalytic renewable energy production and provide an outlook for future related research

Access Adaptive and Thread-Aware Cache Partitioning in Multicore Systems

Cache partitioning is a successful technique for saving energy for a shared cache and all the existing studies focus on multi-program workloads running in multicore systems. In this paper, we are motivated by the fact that a multi-thread application generally executes faster than its single-thread counterpart and its cache accessing behavior is quite different. Based on this observation, we study applications running in multi-thread mode and classify data of the multi-thread applications into shared and private categories, which helps reduce the interferences among shared and private data and contributes to constructing a more efficient cache partitioning scheme. We also propose a hardware structure to support these operations. Then, an access adaptive and thread-aware cache partitioning (ATCP) scheme is proposed, which assigns separate cache portions to shared and private data to avoid the evictions caused by the conflicts from the data of different categories in the shared cache. The proposed ATCP achieves a lower energy consumption, meanwhile improving the performance of applications compared with the least recently used (LRU) managed, core-based evenly partitioning (EVEN) and utility-based cache partitioning (UCP) schemes. The experimental results show that ATCP can achieve 29.6% and 19.9% average energy savings compared with LRU and UCP schemes in a quad-core system. Moreover, the average speedup of multi-thread ATCP with respect to single-thread LRU is at 1.89