Pump Technology Research Articles

Heat pump technology for utilizing the heat of secondary energy resources in the catalytic method of obtaining biodiesel

Heat pump technology for utilisation of heat of secondary energy resources in catalytic method of production of biodiesel fuel is implemented. Algorithm for control of technological parameters at all stages of production of biodiesel fuel is proposed and analysis of parameters of its quality is performed. Heat pump system is represented in the form of two recirculation circuits of low-potential and high-potential heat carriers, preparation of which was carried out in stages of low and high pressure of heat pump. Exergetic analysis was performed, functional dependencies of exergy flows coming out of the considered types of process equipment were obtained. The obtained hybesel fuel complied with the requirements of GOST 23513-79. The proposed heat pump technology reduced specific energy consumption by 13-14%; improve environmental safety at all stages of the process; maximum reduction of spent heat carriers emission into the ambient atmosphere.

사포그릴레이트 염산염을 함유하는 신규 OROS 정의 제제 설계 및 용출 거동

Sarpogrelate hydrochloride (SGH) is a drug that improves ischemic symptoms such as ulcers, pain, and feeling of cold caused by chronic arterial occlusion, and has a short half-life of 0.6 to 0.8 hours. Also, reference drug (SarpodipilⓇ SR tablet) is affected by drug release depending on pH. To overcome this, the osmotic controlled release oral delivery system (OROS) utilizes push-pull osmotic pump (PPOP) technology that can achieve zero-order drug release over 24 hours by osmotic pressure. OROS tablet is double-layer tablet consisting of a drug layer (L200-PEO) and a push layer (H5,000- PEO). OROS tablet coated with a semi-permeable film has a orifice of a certain size made by a laser drill, so that the drug is released at a constant rate. The dissolution of the OROS tablet was not affected by the amount of sodium chloride in the drug layer and the number of orifice, but was affected by amount of coating, cellulose acetate (CA) : polyethylene glycol 3350 (PEG 3350) ratio and the size of orifice. Accordingly, as the amount of coating increased and PEG 3350 decreased, the dissolution rate decreased. The developed OROS tablet (formulation C), unlike the reference drug, is not affected by pH, showing high similarity factors of 76.0, 86.1, and 91.2 at pH 1.2, pH 4.0, and pH 6.8 when compared to distilled water. In conclusion, we developed OROS tablet containing SGH, showing zero-order release that continuously releases the drug for 24 hours regardless of pH, and confirmed the factors affecting dissolution.

Research progress and applications of transcritical carbon dioxide heat pumps: A review

Heat pump technology is an energy-saving technology that can efficiently utilize low-grade energy. It has broad application prospects in building heating, industrial waste heat utilization, new energy and other fields. However, the refrigerants used in traditional heat pump systems have serious negative impacts on the environment, and there is an urgent need to find a safe, environmentally friendly, and efficient alternative refrigerant. As a natural refrigerant, CO2 has good physical and chemical properties and is very suitable as a working fluid in transcritical cycles, showing great advantages in the field of heat pump technology. At present, research on CO2 heat pumps has made certain progress, but there are few reviews of the research status and development trends of CO2 heat pumps in different applications. Therefore, this article systematically summarizes the latest research results of transcritical CO2 heat pumps in different application fields, pointing out the difficulties such as high pressure and low operating efficiency in system design and operation. It also summarizes the latest optimization research on system components, cycle structure, mixed refrigerants and control strategies. The results show that each optimization method can significantly improve system performance, among which mixed refrigerant is the simplest optimization method. Finally, the outlook for CO2 heat pump technology is put forward. With policy support and technological advancement, more comprehensive, energy-saving, and intelligent CO2 heat pump technology will continue to develop and innovate.

Technical Summary of Tunnel Mud Pumping Treatment and a Method of Pressure Reduction by Water Release

With the rapid development of China’s economy and the increasing demand for resources in various regions, the speed and volume of railway operations are increasing, and diseases such as mud pumping and mud pumping in railway tunnels are becoming more and more serious. Although various construction units have taken diverse measures to rectify the diseases, they often have poor results, repeated rectification, and repeated failure, which consumes a lot of financial and material resources but cannot cure the mud pumping disease, allowing the disease to seriously endanger the driving safety of the line. This paper is based on the long-established loess tunnel base mud pumping disease treatment project in the Lanzhou Railway Bureau of the China Railway. Firstly, the influence of train load, structural fracture, and tunnel drainage systems on the mechanism of disease is expounded. Then, the key technologies and processes of the commonly used disease treatment schemes are sorted out and summarized, and the advantages and disadvantages of the commonly used schemes and the additional drainage tunnel and self-priming pump technology proposed in this paper are compared in detail. The analysis shows that the universally used treatment technology applies to the treatment of local mud pumping disease in the tunnel, and there are shortcomings in these measures for the long-established tunnel. The drainage tunnel and self-priming pump technology can reduce and maintain the small content of groundwater in the surrounding rock of the tunnel basement and can resolve the mud pumping disease of the loess tunnel basement from the root. At present, this technology has been applied to many tunnel projects and has achieved certain comprehensive benefits, which could provide a reference for similar projects.

A 2 kW-class free-piston Stirling heat pump prototype suitable for cold regions for domestic heating

Compared with conventional vapour-compression heat pump technology, the free-piston Stirling heat pump technology attracts wide attention for its high efficiency, reliability, and environmental friendliness. In this work, a free-piston Stirling heat pump prototype with a two-kilowatt capacity, which can operate with an outside ambient temperature ranging from -20 to 10 °C, was designed, built and tested. First, numerical simulations were carried out to explore the distributions of the acoustic field and exergy loss. Second, the effects of several operating parameters on the heating performance were numerically investigated in detail. Finally, to validate the accuracy of the simulation results, verification experiments were conducted on the experimental platform of a free-piston Stirling heat pump driven by a dual-opposed linear compressor. Experimental data show that with a hot-end temperature of 45 °C and outside ambient temperature of 0 °C, the prototype achieved a heating capacity of 2253 W with a corresponding COPh of 2.76 (based on PV power input) and a relative Carnot efficiency of 39.1 %; in particular, the prototype was able to achieve a COPh of 2.5 when pumping heat from -20 °C to 45 °C for 3.25 MPa mean pressure. The simulation and experimental results demonstrated that the free-piston Stirling heat pump system has good potential to achieve high efficiency as a heating supply in a cold region.

Lab Investigation Using a Box Model and Image Analysis of a Contaminant Back-Diffusion Process from Low-Permeability Layers

Contaminants stored in low-permeability soils can continue to threaten the adjacent groundwater system even after the aquifer is considered remediated. The redistribution of contaminants from low-to-high-permeability aquifer zones (Back-Diffusion) can generate a long-term plume tail, commonly considered one of the main obstacles to effective groundwater remediation. In this paper, a laboratory test was performed to reproduce the redistribution process from low-permeability silt lenses (k ≈ 1 × 10−7 m/s) to high-permeability sand aquifers (k ≈ 1 × 10−3 m/s). The target of the experimental and numerical approach was finalized to verify what influence the shape and position of the lenses could have, with respect to the bulk flow, on the time necessary to complete the depletion of the dissolved substances present in the lenses. For this purpose, an image analysis procedure was used to estimate the diffusive flux of contaminants released by these low-permeability zones in different boundary conditions. The results obtained in the laboratory test were used to calibrate a numerical model implemented to simulate the Back-Diffusion process. Once calibrated, the numerical model was used to simulate further scenarios to evaluate the influence of the location and shape of the low-permeability lenses on the time necessary to diminish its contaminant content when subjected to a steady-state flow. The numerical model was also used to investigate the effect of different groundwater velocities on the depletion time of the process. The results show that the shape and position of the lens have an important impact on the time necessary to empty the lens, and an increase in the velocity field in the bulk medium (flow rate rising from 1.6 l/h to 2.5 l/h) does not correspond to diminishing total depletion times, as the process is mainly governed by diffusive transport inside the lens. This appears to be significant when the remediation approach relies on pumping technology. Future research will verify the behavior of the released plume in a strongly heterogeneous porous medium.

Pocketable and Smart Electrohydrodynamic Pump for Clothes.

Seamlessly fusing fashion and functionality can redefine wearable technology and enhance the quality of life. We propose a pocketable and smart electrohydrodynamic pump (PSEP) with self-sensing capability for wearable thermal controls. Overcoming the constraints of traditional liquid-cooled wearables, PSEP with dimensions of 10 × 2 × 1.05 cm and a weight of 10 g is sufficiently compact to fit into a shirt pocket, providing stylish and unobtrusive thermal control. Silent operation coupled with the unique self-sensing ability to monitor the flow rate ensures system reliability without cumbersome additional components. The significant contribution of our study is the formulation and validation of a theoretical model for self-sensing in EHD pumps, thereby introducing an innovative functionality to EHD pump technology. PSEP can deliver temperature changes of up to 3 °C, considerably improving personal comfort. Additionally, the PSEP system features an intuitive, smartphone-compatible interface for seamless wireless control and monitoring, enhancing user interaction and convenience. Furthermore, the ability to detect and notify users of flow blockages, achieved by self-sensing, ensures an efficient and long-term operation. Through its blend of compact design, intelligent functionality, and stylish integration into daily wear, PSEP reshapes the landscape of wearable thermal control technology and offers a promising avenue for enhancing personal comfort in daily life.

Load-suspended power backpack for labor saving and energy harvesting from human walk

Long-distance walk with a heavy load such as hiking and field rescue, often leads to accumulative fatigue. And continuous energy support for wearable electronics is often demanded in remote areas. Here, we report a new load-suspended power backpack that can realize labor saving and energy harvesting from human walking. An innovative suspended system is designed to decouple the synchronous movement of backpack and body, which consists of two elastomer-pulley block units and two linear sliding rod units. It also utilizes a new charge pumping technology of triboelectric nanogenerator (TENG) for high-efficient energy conversion, achieved by a specially designed main TENG and two buffer capacitors (BFCs). The main TENG has one top electrode but two bottom ones to build two separated plate variable capacitors for charge storage. The new technology is characterized by using one top electrode to synchronously drive shuttling charges in four pathways between main TENG and BFCs, and generating electricity based on shuttling charges. Consequently, it can reduce the remarkable 32.6% vertical vibrations of load and 26.7% wearing force and provide a high voltage of 820 V and a current of 103.2 μA. The average power in one current pathway is calculated to 84.1 mW (336.4 mW for four ones) with an effective power density of 29.96 mW/g, high enough to light 354 small LEDs, 235 large LEDs, the electronic watch and thermos-hygrometer. The backpack can not only be applied to relieve accumulative fatigue, but also has great potential to be an energy source for continuously driving wearable electronics for various applications.

Thermodynamic and thermo-economic analyses of a coupled heat-pump system for low-grade exhaust-air heat exchange in mines

ABSTRACT Combining mine exhaust waste heat with existing heat pump technology is a promising technical route to realise the efficient extraction and scientific use of low-grade waste heat resources in mines and to solve the problem of insufficient heat supply in remote mining areas. This study proposes a new type of mine-exhaust-air heat exchange coupled with heat-pump waste-heat-utilisation system based on deep enthalpy heat extraction. Using a mining area in Northwest China as a representative case, this study establishes a systematic exergy analytical model and a thermo-economic model. Through an in-depth analysis of the different evaporation temperatures and condensing temperatures, the system’s energy efficiency ratio (COP) reaches its optimal performance, with the total exergy efficiency surpassing 90%. The minimum efficiency of the subsystem return air heat exchanger is 35%. The unit thermal costs of the mine exhaust air waste heat utilisation system and a conventional coal-fired boiler system are 0.1291 and 0.1573 million RMB/kW·h, respectively. This is a thermal economics cost saving of 21%. The studied system demonstrates great economic viability and the potential for energy saving throughout its life cycle.

Performance assessment and working fluid selection for heat recovery ejector heat pump system in cold climatic conditions

The paper aims to analyze the performance and identify suitable working fluids for a new heat recovery ejector heat pump (HREHP) system. This system introduces a flue gas waste exergy recover circuit combined with the traditional ejector heat pump. Considering the factors of performance, environmental impacts, flammability, and fluid type, four working fluids are selected (i.e., R245fa, R365mfc, RE245fa2, and R1233zd(E)). Comparative study initially conducted to demonstrate the advantages of the proposed heat recovery ejector heat pump facility. Subsequently, the effects of the operational parameters on the novel system performance are investigated to derive design and operation criteria through energy and exergy analysis. Finally, sensitive analysis of generation temperature (Tg), flue gas temperature (Tfg,out), and supply water temperature (Tw) on the proposed system is carried out. Compared with traditional air source heat pump, the application of the HREHP shows higher energy efficiency and lower operating costs at lower ambient temperatures. The results indicate that the primary energy efficiency of the proposed system is 27.0 % and 35.56 % higher than that of conventional ejector heat pump cycle and air source heat pump cycle, respectively, at an ambient temperature of −10 °C. Besides, Tg has a stronger effect on the entrainment ratio and heating coefficient of performance; The primary energy efficiency is more sensitive to Tw variation. Lastly, the R365mfc and R1233zd(E) show good potential as the alternative for the R245fa. The design methods, evaluation methods, and operational characteristics obtained in this study can provide reference and guidance for the application of heat recovery ejector heat pump technology in practical engineering.

Thermal economy simulation study for a carbon capture power plant with combined heat and power based on absorption heat pump technology

The Combined Heat and Power (CHP) system represents an energy-efficient and environmentally-friendly approach to energy utilization. However, in the context of the “carbon peaking and carbon neutrality” strategy, ensuring low-carbon operation of CHP systems becomes imperative. In this study, based on absorption heat pump (AHP), an extraction condensing carbon capture (EC&CC) CHP coupled system and a low-pressure cylinder zero-output carbon capture (LCZ&CC) CHP coupled system are proposed, respectively. Furthermore, under the 100 % turbine heat acceptance (THA) operating condition, a variable operating condition study of heating load and carbon capture capacity is conducted. The results demonstrate that under identical heating load, the EC&CC CHP coupled system has superior thermal economy, with an average reduction of 1011.03 kJ/kWh in heat consumption of power generation and 34.54 g/kWh in coal consumption of power generation compared with the LCZ&CC CHP coupled system; For equivalent carbon capture capacity, the LCZ&CC CHP coupled system has superior thermal economy, with an average reduction of 771.28 kJ/kWh in heat consumption and 26.35 g/kWh in coal consumption of power generation compared with the EC&CC CHP coupled system. The EC&CC CHP coupled system has lower CO2 capture heat consumption, resulting in an average reduction of 135.67 t/h in carbon capture extraction compared with the LCZ&CC CHP coupled system. This study can provide guidance for optimizing the design of carbon capture CHP coupled systems.

Investigating the efficiency of air-source heat pumps in the secondary school physics laboratory

This paper presents an experimental method for investigating the coefficient of performance of air-source heat pumps for secondary age children and links this to ideas about energy efficiency. It was developed and trialled in a secondary school in the West Midlands of England in response to literature that reveals climate anxiety to be increasing amongst young people around the world and their resulting desire to take action. Links are made to the topic of energy efficiency in the current physics school curriculum in England which is used, where possible, to explain the results of the investigation with suggestions for where extensions might be made in future to facilitate a more complete understanding by pupils. Links to wider societal change in the decarbonisation of home heating in the UK as part of the national response to climate change are explored and an argument is made for the viability and necessity of including the technology of air-source heats pumps in the physics curriculum for all children.

Design and evaluation of EMPIX2, a 100 kfps, high dynamic range pixel detector readout ASIC for electron microscopy

EMPIX2 is a novel hybrid pixel detector readout ASIC for electron microscopy with a maximum frame rate of 100 kfps and a very large dynamic range (5 × 105:1). It features 128 × 128 square pixels at a pitch of 150 μm. Adaptive gain switching and charge pump technology are applied to enhance the dynamic range. The pixels can operate in two modes: pulse mode and continuous mode. In pulse mode, ultra-fast gain switching enables a rapid response to pulsed electron sources, making it highly suitable for UEM applications. In continuous mode, the power consumption and dynamic range are optimized for STEM applications. The readout is frame-based, and digital image data is output by 64 pairs of LVDS drivers working in DDR mode at a clock frequency of 400 MHz. A dedicated data acquisition system was developed for the transmission and processing of the image data. Preliminary verification of the readout chip was performed using an on-chip calibration source.

Artificial neural network model for predicting CO2 heat pump behaviour in domestic hot water and space heating systems

The natural refrigerant, CO2, possesses thermophysical properties that make it highly suitable for domestic hot water (DHW) production using heat pump technology. In this study, the development and validation of an artificial neural network (ANN) model that enables efficient design and control of a CO2 heat pump is presented. The study employs experimental data from a CO2 heat pump with a nominal heat capacity of 8 kW. The fully instrumented rig includes the heat pump and a pump rig designed to generate system temperatures representative of various space heat and DHW demands. A comprehensive dataset was generated through systematic variation of inlet temperatures and setpoints. The ANN provides predictions for outlet temperatures, heat production, and electricity consumption utilizing inlet flow rates, temperatures, and setpoints as inputs. These predictions are important for condition monitoring or in a smart operation management framework that determines optimal schedules for the machine.

Estimating Thermal Impact on Groundwater Systems from Heat Pump Technologies: A Simplified Method for High Flow Rates

This research delves into the potential thermal effects on underground water systems caused by the use of thermal technologies involving extraction and injection wells. We developed a unique approach that combines straightforward calculations with computer-based modeling to evaluate thermal impacts when water flow rates exceed 2 L/s. Our model, based on a system with two wells and a steady water flow, was used to pinpoint the area around the thermal technology where the temperature varied by more than 1 °C. Our findings suggest that the data-based relationships we derived from our model calculations provide a cautious estimate of the size of the affected area, or ‘thermal cloud’. However, it is important to note that our model’s assumptions might not fully account for the complex variables present in real-world underground water systems. This highlights a need for more research and testing. A key contribution of our study is the development of a new method to assess the thermal impact of operations involving heat pumps. In conclusion, while our proposed method needs more fine-tuning, it shows promise in estimating temperature changes within water-bearing rock layers, or aquifers. This is crucial in the effective use of thermal technologies while also ensuring the protection and sustainable management of our underground water resources.

Heat pump supply chain environmental impact reduction to improve the UK energy sustainability, resiliency and security

Various heat pump technologies are examined from an environmental perspective using a life cycle assessment approach. The investigated heat pump systems utilize air, ground, and water as their energy sources. Additionally, an innovative heat pump powered by green hydrogen is investigated in this study, to evaluate its environmental impacts and potential to commercialise on a large scale. A range of supply chain scenarios is explored, considering the main suppliers of the UK market. The reshoring heat pump industry and supply chain are evaluated to enhance energy resilience and security within the UK. The findings indicate that the hydrogen-based heat pump presents a promising option for the UK market, offering the advantages of reducing stress on the national grid network and minimizing the environmental impacts associated with the supply chain. Furthermore, a forecasting analysis is conducted based on the UK's net-zero emission plan to provide insight into future developments.

An advanced exhausting airflow photovoltaic curtain wall system coupled with an air source heat pump for outdoor air treatment: Energy-saving performance assessment

Building integrated photovoltaic (BIPV) and air source heat pump (ASHP) technologies have emerged as promising solutions for building energy conservation. However, traditional solar buildings face limitations such as overheating, limited efficiency, and singular functionality; additionally, ASHPs suffer from a low coefficient of performance (COP) due to high condensing temperatures or low evaporating temperatures; the process of outdoor air handling proves energy-intensive. To address these challenges, this study proposes an innovative exhausting ventilation PV curtain wall system coupled with ASHP units (EVPV-HP) for outdoor air treatment. This system features a fine combination of PV cooling, supply air reheating, and heat recovery from both the PV facade and exhaust air. The mathematical model of the BIPV curtain wall, based on energy balance equations, is developed and solved using Matlab programming. This model is then combined with the ASHP system model established in TRNSYS to predict the year-round energy performance of the hybrid system. The findings demonstrate that the EVPV-HP system achieves seasonal energy efficiencies of 5.08 for cooling and 4.06 for heating operation modes. Compared to a conventional system, the EVPV-HP system enhances yearly energy efficiency by 17.05 % owing to increased PV production, reduced air-conditioning load, and improved COP. Furthermore, parametric analysis suggests that the system exhibits improved performance under higher solar irradiation and hotter weather conditions during summer. Conversely, in winter, the system performs better under lower ambient temperatures with incident radiation around 800 W/m2.

Simulating Potential Impacts of Solar MajiPump on the Economy and Nutrition of Smallholder Farmers in Sub-Humid Ethiopia

Irrigation is widely considered a potential means to improve agricultural productivity, nutrition, and income, as farmers can carry out farming and production year-round. However, the feasibility of irrigation technologies is highly dependent on the long-term economic return farmers achieve. Solar-based irrigation could address the challenges of underinvestment in irrigation within Africa. Evidence on the economic viability of the adopted solar pumps such as MajiPump is very scant and focused on ex post evaluation. This study evaluated the income and nutritional feasibility of solar-powered irrigation using the MajiPump in sub-humid Ethiopian highlands using the farm simulation (FARMSIM) model and compared it with the manual pulley system. Results from the FARMSIM model show that farmers’ adoption of Maji solar pump technology to grow vegetables is economically feasible with financial support such as credit or loan for initial and capital investment to acquire the pump. The average profit under the solar MajiPump, drip irrigation, and conservation agriculture was 3.6 times higher than that of the baseline scenario. While the pulley technology provides the same amount of irrigation water to grow vegetables, its feasibility is limited due to high labor costs and time, estimated to be more than seven times the baseline. The simulation results show that the alternative scenarios’ nutrition level has improved relative to other scenarios and met the minimum daily average nutrition requirement level for proteins, iron, and vitamin A but fell short in fat, calcium, and calories. The results suggest that farmers who adopt improved small-scale irrigation technologies (solar MajiPump and drip system) have a higher potential to increase production and income from irrigated crops and improve their nutrition if part of the income generated is used to purchase supplemental food for their nutrition.

Common Complications and Cardiopulmonary Resuscitation in Patients with Left Ventricular Assist Devices: A Narrative Review.

Heart failure remains a major global burden regarding patients' morbidity and mortality and health system organization, logistics, and costs. Despite continual advances in pharmacological and resynchronization device therapy, it is currently well accepted that heart transplantation and mechanical circulatory support represent a cornerstone in the management of advanced forms of this disease, with the latter becoming an increasingly accepted treatment modality due to the ongoing shortage of available donor hearts in an ever-increasing pool of patients. Mechanical circulatory support strategies have seen tremendous advances in recent years, especially in terms of pump technology improvements, indication for use, surgical techniques for device implantation, exchange and explantation, and postoperative patient management, but not in the field of treatment of critically ill patients and those undergoing cardiac arrest. This contemporary review aims to summarize the collected knowledge of this topic with an emphasis on complications in patients with left ventricular assist devices, their treatment, and establishing a clear-cut algorithm and the latest recommendations regarding out-of-hospital or emergency department management of cardiac arrest in this patient population.

Pemanfaatan Teknologi Pompa Portabel Tenaga Surya untuk Sistem Irigasi Kebun

The Community Service Program (PKM) aims to solve the problems faced by farmer group partners, such as: (1) unequal financial capabilities in each member of the farmer group, (2) less good agricultural yields if smoke appears during the long dry season, and (3) high operational costs because they depend on fuel consumption for the plant watering process. The implementation of core activities in this PKM program consists of two stages, namely; (1) solar cell pump assembly training to provide solutions for partners who are not familiar with solar-powered portable water pump technology and still depend on using fuel pumps as a means of watering plants, and (2) solar cell pump operation and maintenance training to provide solutions for partners who cannot operate and maintain solar-powered portable water pumps.