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Shen, Bo

Publications and source records attributed to Shen, Bo.

At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Development and validation of quasi-steady-state heat pump water heater model having stratified water tank and wrapped-tank condenser

Heat pump water heater systems (HPWH) introduce new challenges for design and modeling tools, because they require vapor compression system balanced with a water storage tank. In addition, a wrapped-tank condenser coil has strong coupling with a stratified water tank, which leads HPWH simulation to a transient process. To tackle these challenges and deliver an effective, hardware-based HPWH equipment design tool, a quasi-steady-state HPWH model was developed based on the DOE/ORNL Heat Pump Design Model (HPDM). Two new component models were added via this study. One is a one-dimensional stratified water tank model, an improvement to the open-source EnergyPlus water tank model, by introducing a calibration factor to account for bulk mixing effect due to water draws, circulations, etc. The other is a wrapped-tank condenser coil model, using a segment-to-segment modeling approach. In conclusion, the HPWH system model was validated against available experimental data. After that, the model was used for parametric simulations to determine the effects of various design factors.

42 ENGINEERING↗
DOE OSTI2017

Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants

Based on laboratory investigations for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), the DOE/ORNL Heat Pump Design Model was used to model the two RTUs and the models were calibrated against the experimental data. We compared the compressor efficiencies and heat exchanger performances. An efficiency-based compressor mapping method was developed. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting optimal configurations. The results illustrate that all the R-22 low GWP refrigerants will lead to slightly lower COPs. ARM-20B appears to be the best R-22 replacement at normal conditions. At higher ambient temperatures, ARM-20A exhibits better performance. All R-410A low GWP candidates will result in similar or better efficiencies than R-410A. R-32 has the best COP while requiring the smallest compressor. Finally, R-452B uses the closest compressor displacement volume and achieves the same efficiency as R-410A.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Performance optimization of CO 2 heat pump water heater

A preliminary analysis was conducted to analyze the performance of a heat pump water heater (HPWH) that uses CO 2 as the refrigerant. A model to predict the performance was developed and calibrated based on the experimental data for an existing HPWH using a CO 2 refrigerant. The calibrated model was then used to run a parametric analysis in which factors such as water supply temperature, water circulation rate, tank stratification, and condenser configuration were considered. The performance of a commercial CO 2 system was compared with that of a similar system using R-134a as the refrigerant. It was found that CO 2 HPWH performance was comparable to that of an R-134a HPWH, more so for a separated gas cooler configuration. For comparable performance, the compressor size and the tube-in-tube heat exchanger (condenser/gas cooler) size were compared for CO 2 - and R-134a-based systems. Finally, the impact of the water circulation rate on the water temperature stratification in the tank, an essential requirement for higher performance for CO 2 HPWH systems was also investigated.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

EnergyPlus

EnergyPlus(TM) is a whole building energy simulation program that engineers, architects, and researchers use to model both energy consumption - for heating, cooling, ventilation, lighting and plus and process loads - and water use in buildings.

New, JoshuaR↗
DOE OSTI2017

U.S. Experiences in Tackling Energy and Environmental Challenges of Boiler System

In the U.S., energy consumption by steam and process heat combined accounts for over 50% of the total energy use from industrial systems (see Figure 1). The use of boilers, process heaters, and furnaces for generating steam and heat in industrial facilities, commercial settings, and institutions consumes significant amounts of energy and is one of major sources of hazardous air pollutants, which contribute significantly to local pollution and global climate change. To address the energy and environmental challenges caused by boiler systems in the U.S., the country has taken a series of actions to reduce emissions from industrial, commercial and institutional boilers, improve the efficiency of steam systems, replace coal with cleaner energy resources, and promote the wider use of combined heat and power (CHP).

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2017

Stabilizing Fe Nanoparticles in the SmCo 5 Matrix

In this paper, we report a new strategy for stabilizing Fe nanoparticles (NPs) in the preparation of SmCo 5 –Fe nanocomposites. We coat the presynthesized Fe NPs with SiO 2 and assemble the Fe/SiO 2 NPs with Sm–Co–OH to form a mixture. After reductive annealing at 850 °C in the presence of Ca, we obtain SmCo 5 –Fe/SiO 2 composites. Following aqueous NaOH washing and compaction, we produced exchange-coupled SmCo 5 –Fe nanocomposites with Fe NPs controlled at 12 nm. In conclusion, our work demonstrates a successful strategy of stabilizing high moment magnetic NPs in a hard magnetic matrix to produce a nanocomposite with tunable magnetic properties.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Expanding Energy Performance Contracting in china: policy solutions and market mechanisms

Energy performance contracting is an important market mechanism that uses energy savings to pay over time for the upfront costs of energy efficiency retrofits in buildings, industries, and other types of facilities. Through energy performance contracts (EPCs), Energy Service Companies (ESCOs) play an important role in implementing energy efficiency retrofits. Both China and the United States have large markets for EPCs and significant opportunities for growth. The Chinese government has made great efforts in promoting the country’s ESCO business and expanding its EPC markets. This paper makes a series of recommendations for China to adopt more ambitious policy measures to encourage deep energy savings projects via EPCs. These recommendations are built on initial insights from a white paper developed by researchers at the Pacific Northwest National Laboratory and the Lawrence Berkeley National Laboratory with the assistance from the ESCO Committee of China’s Energy Conservation Association (EMCA). Key recommendations are listed below.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2017

R1234yf and R1234ze(E) as low-GWP refrigerants for residential heat pump water heaters; Le R1234yf et le R1234ze(E) comme frigorigènes à faible GWP pour des chauffe-eau domestiques à pompe à chaleur

Owing to the growing concerns about the relatively high global warming potential (GWP) of current refrigerants, a serious effort is currently in progress to find lower-GWP substitutes. The hydrofluoroolefin (HFO)-based refrigerants R1234yf and R1234ze(E) are being considered for use in multiple heating, ventilation, air conditioning, and refrigeration applications because of their very low GWP. A study was conducted to model a residential heat pump water heater using these HFOs. A system model was calibrated using experimental data and the calibrated model was used to evaluate the potential of HFOs to replace R134a. A series of parametric analyses were used to investigate the impacts of condenser wrap pattern, condenser tube size, evaporator size, and heat loss factor from the storage tank. It has been shown that both R1234yf and R1234ze(E) can be substituted for R134a with comparable performance and no substantial modifications to the original system. Finally, this study presents a detailed feasibility analysis for successful replacement of high-GWP refrigerants with low-GWP refrigerants with acceptable performance.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Air-Source Integrated Heat Pump System Development – Final Report

Between October 2007 and September 2017, Oak Ridge National Laboratory (ORNL) and Lennox Industries, Inc. (Lennox) engaged in a Cooperative Research and Development Agreement (CRADA) to develop an air-source integrated heat pump (AS-IHP) system for the US residential market. The Lennox AS-IHP concept consisted of a high-efficiency air-source heat pump (ASHP) for space heating and cooling services and a separate heat pump water heater/dehumidifier (WH/DH) module for domestic water heating and dehumidification (DH) services. A key feature of this system approach with the separate WH/DH is capability to pretreat (i.e., dehumidify) ventilation air and dedicated whole-house DH independent of the ASHP. Two generations of laboratory prototype WH/DH units were designed, fabricated, and lab tested. Performance maps for the system were developed using the latest research version of the US Department of Energy/ORNL heat pump design model (Rice 1992; Rice and Jackson 2005; Shen et al. 2012) as calibrated against the lab test data. These maps served as the input to TRNSYS (Solar Energy Laboratory et al. 2010) to predict annual performance relative to a baseline suite of equipment meeting minimum efficiency standards in effect in 2006 (i.e., a combination of an ASHP with a seasonal energy efficiency ratio (SEER) of 13 and resistance water heater with an energy factor (EF) of 0.9). Predicted total annual energy savings (based on use of a two-speed ASHP and the second-generation WH/DH prototype for the AS-IHP), while providing space conditioning, water heating, and dehumidification for a tight, well-insulated 2600 ft2 (242 m2) house at three US locations, ranged from 33 to 36%, averaging 35%, relative to the baseline system. The lowest savings were seen at the cold-climate Chicago location. Predicted energy use for water heating was reduced by about 50 to 60% relative to a resistance WH.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Long non-coding RNA FBXL19-AS1 plays oncogenic role in colorectal cancer by sponging miR-203

Long non-coding RNAs (lncRNAs) have emerged as critical regulators of the progression of human cancers, including colorectal cancer (CRC). The study of genome-wide lncRNA expression patterns in metastatic CRC could provide novel mechanism underlying CRC carcinogenesis. In here, we determined the lncRNA expression profiles correlating to CRC with or without lymph node metastasis (LNM) based on microarray analysis. We found that 2439 lncRNAs and 1654 mRNAs were differentially expressed in metastatic CRC relative to primary CRC. Among these dysregulated lncRNAs, FBXL19-AS1 was the most significantly upregulated lncRNA in metastatic tumors. Functionally, knockdown of FBXL19-AS1 played tumor-suppressive effects by inhibiting cell proliferation, migration and invasion in vitro and tumor growth and metastasis in vivo. Overexpression of FBXL19-AS1 was markedly correlated with TNM stage and LNM in CRC. Bioinformatics analysis predicted that miR-203 was potentially targeted by FBXL19-AS1, which was confirmed by dual-luciferase reporter assay. Pearson's correlation analysis showed that miR-203 expression was negatively related to FBXL19-AS1 in tumor tissues. Finally, miR-203 inhibition abrogated the effect of FBXL19-AS1 knockdown on the proliferation and invasion of LoVo cells. Our results reveal the cancer-promoting effect of FBXL19-AS1, acting as a molecular sponge in negatively modulating miR-203, which might provide a new insight for understanding of CRC development. - Highlights: • LncRNA expression signature was different between metastatic and primary tumors. • Knockdown of FBXL19-AS1 inhibits proliferation, migration and invasion in vitro. • Knockdown of FBXL19-AS1 inhibits tumorigenesis and metastasis in vivo. • FBXL19-AS1 was upregulated in CRC tissues and related with lymph node metastasis. • FBXL19-AS1, acting as a molecular sponge in negatively regulating miR-203.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Select Components and Finish System Design of a Window Air Conditioner with Propane

This report describes the technical targets for developing a high efficiency window air conditioner (WAC) using propane (R-290). The baseline unit selected for this activity is a GE R-410A WAC. We established collaboration with a Chinese rotary compressor manufacturer, to select an R-290 compressor. We first modelled and calibrated the WAC system model using R-410A. Next, we applied the calibrated system model to design the R-290 WAC, and decided the strategies to reduce the system charge below 260 grams and achieve the capacity and efficiency targets.

42 ENGINEERING↗
DOE OSTI2017

Energy Efficient Clothes Dryer - Final Report

The purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC (the "Contractor") and General Electric Company, (herein "Participant") acting primarily through its GE Appliances business component, is to conduct research and development to evaluate the technical and commercial viability of a residential heat pump clothes dryer that enables reduced energy consumption by utilizing waste heat from the clothes drying process.

42 ENGINEERING↗
DOE OSTI2017

Commercial Integrated Heat Pump with Thermal Storage --Demonstrate Greater than 50% Average Annual Energy Savings, Compared with Baseline Heat Pump and Water Heater (Go/No-Go) FY16 4th Quarter Milestone Report

For this study, we authored a new air source integrated heat pump (AS-IHP) model in EnergyPlus, and conducted building energy simulations to demonstrate greater than 50% average energy savings, in comparison to a baseline heat pump with electric water heater, over 10 US cities, based on the EnergyPlus quick-service restaurant template building. We also assessed water heating energy saving potentials using ASIHP versus gas heating, and pointed out climate zones where AS-IHPs are promising.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Finalize field testing of cold climate heat pump (CCHP) based on tandem vapor injection compressors

This report describes the system diagram and control algorithm of a prototype air-source cold climate heat pump (CCHP) using tandem vapor injection (VI) compressors. The prototype was installed in Fairbanks, Alaska and underwent field testing starting in 09/2016. The field testing results of the past six months, including compressor run time fractions, measured COPs and heating capacities, etc., are presented as a function of the ambient temperature. Two lessons learned are also reported.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Feasibility analysis of a Commercial HPWH with CO 2 Refrigerant

A scoping-level analysis has conducted to establish the feasibility of using CO 2 as refrigerant for a commercial heat pump water heater (HPWH) for U.S. applications. The DOE/ORNL Heat Pump Design Model (HPDM) modeling tool was used for the assessment with data from a Japanese heat pump water heater (Sanden) using CO 2 as refrigerant for calibration. A CFD modeling tool was used to further refine the HPDM tank model. After calibration, the model was used to simulate the performance of commercial HPWHs using CO 2 and R-134a (baseline). The parametric analysis concluded that compressor discharge pressure and water temperature stratification are critical parameters for the system. For comparable performance the compressor size and water-heater size can be significantly different for R-134 and CO 2 HPWHs. The proposed design deploying a gas-cooler configuration not only exceeds the Energy Star Energy Factor criteria i.e. 2.20, but is also comparable to some of the most efficient products in the market using conventional refrigerants.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Compare optimized performance results for packaged RTU using all alternative refrigerants FY17 1st Quarter Milestone Report

Based on the laboratory investigation in FY16, for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), we used the DOE/ORNL Heat Pump Design Model to model the two RTUs and calibrated the models against the experimental data. Using the calibrated equipment models, we compared the compressor efficiencies, heat exchanger performances. An efficiency-based compressor mapping method was developed, which is able to predict compressor performances of the alternative low GWP refrigerants accurately. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting their preferred configurations at the same cooling capacity and compressor efficiencies.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗