Pipeline Layout Research Articles

Generation Method for HVAC Systems Design Schemes in Office Buildings Based on Deep Graph Generative Models

The design process of heating, ventilation, and air conditioning (HVAC) systems is complex and time consuming due to the need to follow design codes. Since the design standards are not fixed, the final outcome often depends on the designer’s experience. The development of building information modeling (BIM) technology has made information throughout the building lifecycle more integrated. BIM-based forward design is now widely used, providing a data foundation for combining HVAC system design with machine learning. This paper proposes an unsupervised learning method based on deep graph generative models to uncover hidden design patterns and optimization strategies from the design results. We trained and validated four deep graph generative models—GAE, GNF, GAN, and diffusion—using HVAC system terminal pipeline layout data. Accuracy and precision metrics were used to compare the generated designs with automated forward design solutions, assessing the models’ ability to capture both local variations and broader changes in design logic. A graph-neural-network-based evaluation method was employed to measure the models’ capacity to detect changes. The results indicate that all four models achieved prediction accuracies exceeding 90% and precision rates above 75%. The models effectively captured both local modifications made by designers and global design changes, showing greater sensitivity to global layout adjustments than to local updates. When comparing the results generated by deep graph generative models and the actual design, it is obvious that the accuracy of the predictions varies significantly due to the complexity of the test buildings.

Synchronization Optimization of Pipeline Layout and Pipe Diameter Selection in a Drip Irrigation Network System Based on the Jaya Algorithm

To address the complexity and high computational burden in the design of drip irrigation networks, the Jaya algorithm is utilized to study factors affecting project costs, including equipment and pipeline depreciation and the operation and management costs of the irrigation area. A mathematical model of synchronization optimal design of pipe layout and pipe diameter selection in a drip irrigation network system with constraints on pipe diameter, flow velocity, and pipe pressure is established. Using an irrigation district in Xinjiang, China, as an example, the Jaya algorithm optimization design program was run independently 50 times, and the relative deviation of each optimization result from the optimal solution was calculated. The results show that the annual cost per unit area o is reduced to 635.99 RMB/hm2, a 25.34% reduction compared to the original engineering program, and the investment-saving effect is obvious. The relative deviation is controlled within 3%, which shows that the algorithm has stable convergence performance and can meet the requirements of actual engineering design. The Jaya algorithm eliminates the need for parameter tuning, and it excels in cost savings, algorithm stability, and computational accuracy, making it an effective method for the single-objective optimization design of drip irrigation networks.

A national-scale high-resolution CCUS-shared pipeline layout for retrofitting multisectoral plants via onshore-offshore geological storage

Carbon capture utilization and storage (CCUS) is an indispensable process to mitigate climate change. However, a precise and feasible CCUS layout with realistic geospatial connectivity is essential to support the prospective deployment of multisectoral plants on a national scale. This study proposed an onshore-offshore CCUS source-sink matching model, distinguished by CO2 source-sink dataset enhancement, realistic pipeline network optimization, and onshore-offshore geospatial connectivity to accurately map China's high-resolution CCUS layout. The findings showed that China's multisectoral CCUS supply potential of coal-fired power, steel, cement, and coal chemicals was approximately 1.75, 0.77, 0.56, and 0.23 Gt/a CO2, respectively. A complete geospatial connectivity pattern was established by connecting 1186 multisectoral CO2 sources with 307 onshore and 22 offshore storage sites via the shared pipeline network of 80,700km, involving plant-level cost heterogeneity, industry competition, and CCUS cluster identification. This model can be applied to other countries or globally to enhance CCUS layout strategies.

Potential assessment of CO2 source/sink and its matching research during CCS process of deep unworkable seam

It is of great significance for the engineering popularization of CO2-ECBM technology to evaluate the potential of CCUS source and sink and study the matching of pipeline network of deep unworkable seam. In this study, the deep unworkable seam was taken as the research object. Firstly, the evaluation method of CO2 storage potential in deep unworkable seam was discussed. Secondly, the CO2 storage potential was analyzed. Then, the matching research of CO2 source and sink was carried out, and the pipe network design was optimized. Finally, suggestions for the design of pipe network are put forward from the perspective of time and space scale. The results show that the average annual CO2 emissions of coal-fired power plants vary greatly, and the total emissions are 58.76 million tons. The CO2 storage potential in deep unworkable seam is huge with a total amount of 762 million tons, which can store CO2 for 12.97 years. During the 10-year period, the deep unworkable seam can store 587.6 million tons of CO2, and the cumulative length of pipeline is 251.61 km with requiring a cumulative capital of $ 4.26 × 1010. In the process of CO2 source-sink matching, the cumulative saving mileage of carbon sink is 98.75 km, and the cumulative saving cost is $ 25.669 billion with accounting for 39.25% and 60.26% of the total mileage and cost, respectively. Based on the three-step approach, the whole line of CO2 source and sink in Huainan coalfield can be completed by stages and regions, and all CO2 transportation and storage can be realized. CO2 pipelines include gas collection and distribution branch lines, intra-regional trunk lines, and interregional trunk lines. Based on the reasonable layout of CO2 pipelines, a variety of CCS applications can be simultaneously carried out, intra-regional and inter-regional CO2 transport network demonstrations can be built, and integrated business models of CO2 transport and storage can be simultaneously built on land and sea. The research results can provide reference for the evaluation of CO2 sequestration potential of China's coal bases, and lay a foundation for the deployment of CCUS clusters.

Energy loss analysis of a double-suction centrifugal pump using in pump mode and turbine mode

As an economical energy recovery device, pump as turbine (PAT) is widely used in micro-hydropower stations and the chemical industry. The inlet and outlet pipelines connected to the double-suction pump are on the same horizontal line. As the pipeline layout is very convenient, in some chemical industries, the way of residual pressure energy utilization is increasing using the double-suction pump as a turbine. Based on numerical simulation, experimental verification, and entropy generation theory, the energy loss rule of each flow component in the pump mode and turbine mode under different flow rates is compared and analyzed. The results show that when the double-suction pump is used as a turbine, the flow rate at the best efficiency point (BEP) in the turbine mode shifts to a large flow rate by 30.89% and the BEP efficiency decreases by 1.30%. In the pump mode and turbine mode, the main energy loss component is the impeller, and the turbulent entropy generation power and the wall entropy generation power are the main sources of energy loss. The energy loss in the suction chamber and impeller increases sharply, and the energy loss is primarily enhanced in the blade trailing edge and the tongue near due to the unsteady flow in the turbine mode. Due to the complex structure, the spiral suction chamber is not suitable for the flow direction of the fluid flow out of the impeller, and the flow state inside the impeller is negatively affected by the suction chamber in the turbine mode. This paper provides a theoretical basis for the design and application of double-suction centrifugal PAT.

Coupled system for underground heating exchange and solar heat-humidity regulation in greenhouse: Experimental study and simulation analysis

In winter, greenhouses located in mid to high latitudes are required a function of dehumidification and warming due to the low outdoor temperature. Focusing on small spires greenhouses, this study regulates the low temperature and high humidity environment inside the greenhouse and proposes a new-type of greenhouse heat and humidity regulation system by combining composite solid desiccant dehumidification with ground heat exchange system. The greenhouse internal environment is warmed and dehumidified at night by utilizing the adsorption effect of the compound dehumidifier and the sensible heat exchange between the heat exchange system in the ground and the greenhouse. Solar thermal energy is collected during the day using multi-curved tank collector (MTC) for thermal storage in the geothermal system and desiccant desorption. The rationality of pipeline layout is verified through CFD simulation, and the indoor temperature and humidity distribution during the system operation is explored. The experimental results show that the moisture adsorption capacity of the composite desiccant SG-CaCl2 for 10h is 0.511 g/g. The optimal regeneration temperature is 80–100 °C. This system can reduce the nighttime relative humidity of the greenhouse in winter from 96.5 % to 83.6 %, and the average indoor air temperature after warming is 12.8 °C. The heat exchange efficiency of the underground heating exchange system is 0.38. During the desorption phase on daytime, the maximum outlet temperature of MTC is 103.8 °C, and the average heat collection efficiency is 0.42. The system can effectively regulate the air environment in the greenhouse to the appropriate zone for crop growth by combining solar thermal collector technology with recyclable solid dehumidification technology.

Jilin city central wastewater treatment plant renovation design scheme

Jilin City is one of the top ten famous Chinese cities worth introducing to the world. To further improve the construction of urban infrastructure and meet the needs of the economic and social development of Jilin City, the Jilin City Government Joint Development and Reform Commission and the Ecological Environment Bureau decided to expand and renovate the former Jilin City wastewater treatment plant. This study designs a wastewater treatment plant by comprehensively considering the policy needs and the local basic background characteristics of Jilin to solve the wastewater overflow problem. The design modified the anaerobic tank and Carroussel oxidation ditch processes, which have more advantages than traditional treatment processes, mainly including better BOD, nitrogen and phosphorus removal efficiency, less power consumption, and lower operating costs. This treatment plant design contains two special characteristics: the design considers the overall plan and pipeline layout of the wastewater treatment plant, and the size data of each module are calculated through theoretical study conforming to the real case.

A preliminary assessment of CO2 capture, transport, and storage network for China's steel sector

Carbon capture and storage (CCS) has emerged as a promising way for achieving deep decarbonization of China's steel sector. Large-scale CCS deployment necessitates a comprehensive source-sink matching analysis to offer early engineering guidance. To address this issue, this study conducted a source-sink matching analysis of China's steel sector, assessing CO2 sources, CO2 storage capacities and costs, and CO2 pipeline layouts under three capture targets. The findings reveal an obvious spatial mismatch between CO2 sources and potential CO2 sinks for China's steel sector. CO2 sources are mainly situated in eastern China, while main CO2 storage sites are located in western China. The average unit costs of CCS under low (30%), medium (60%), and full capture (90%) targets are 83, 91, and 118 $/t CO2, respectively. In particular, as capture target increases, the CO2 transportation cost will supersede the capture cost and dominate the average CCS unit cost, owing to the construction of longer pipelines. This study recommends prioritizing CCS demonstration with steel plants in regions having suitable CO2 storage basins nearby. Moreover, future investigations should concentrate on on-site experiments of CO2 storage basins and the technology development of offshore carbon storage in China.

Research on Intelligent Control Model of Laboratory Safety Risks in Colleges and Universities Based on Digital Twins

This paper focuses on developing an intelligent management model for safety risks in university laboratories based on digital twin technology to improve safety management efficiency and accuracy. The virtual simulation environment of the laboratory is constructed by using digital twin technology, which is combined with the DEMATEL-ISM method for risk identification and analysis. Fault tree analysis (FTA) method was utilized to construct a laboratory safety accident fault tree to identify and assess potential risk factors. It was found that safety risks in laboratories can be effectively identified and controlled by digital twin technology. The risk assessment showed that unregulated drug storage, lack of monitoring and warning devices, insufficient safety awareness, inadequate systems and unreasonable layout of water, electricity and gas pipelines were the main risk factors. The empirical analysis of 11 university laboratories revealed that most of the laboratories were at a “relatively safe” level. The intelligent management model of safety risk in university laboratories based on digital twins can effectively identify and assess the safety risk, provide a scientific basis for the formulation of safety management measures, and thus improve the efficiency and accuracy of laboratory safety management.

Digital twin enhanced agile design of ship pipeline systems

The shipbuilding industry plays a pivotal role in national strategic security and economic development, and one critical challenge is the pipeline layout design problem. It predominantly relies on designers’ subjective experience, and it is marked by a lack of efficient knowledge sharing and the absence of smart pipe routing algorithms. This paper proposes an agile design system, which integrates ship pipeline design knowledge management, semi-automatic design that involves frequent interaction with human designers, and automatic rule checking. The framework is refined by digital twin concepts, facilitating close collaboration between physical and digital systems. The paradigm shift holds the potential to substantially enhance the efficiency of ship pipeline layout design, while concurrently reducing the reliance on manual labor.

Optimization and Simulation Analysis of Furnace Structure for Regenerative Thermal Oxidizer

Volatile Organic Compounds (VOCs) significantly threaten the atmospheric environment. Currently, common methods for the recovery and treatment of VOCs include adsorption, solution absorption, photocatalytic oxidation, and high-temperature oxidation. Among them, the Regenerative Thermal Oxidizer (RTO) is a scheme for high-temperature oxidation treatment of VOCs, which applies aerospace heat transfer and combustion technology to the treatment of VOCs, and the removal efficiency of VOCs can reach over 99%. Considering the high temperature and possible instantaneous overpressure during the combustion process, a three-dimensional flow model of the bottom air distribution chamber and heat storage chamber was established to solve the technical difficulties of the gas flow field in the existing RTO and improve the safety and stability of the overall flow. Simulated the gas flow field and analysed the distribution pattern of the gas flow rate. In response to the uneven distribution of airflow caused by the pipeline layout, orifice plates were installed at the bottom of the furnace, and various orifice plate designs were considered. The results indicate that adding slanted orifice plates can improve flow conditions and enhance safety while meeting practical needs.

Снижение пульсаций давления газа в линии всасывания поршневого компрессора при использовании дроссельных шайб

This article discusses the problem of combating pressure fluctuations in the suction line of piston compressors. As you know, incorrect calculation of communications can lead to accidents of compressor equipment. Therefore, special attention must be paid to the layout of pipelines and equipment, while avoiding resonance phenomena. One way to combat pressure pulsations in the suction line is to install diaphragms. This method is the cheapest and easiest to implement, especially for compressors already in operation. The experimental studies carried out confirmed the known data that the area of the diaphragm opening should be four times smaller than the diameter of the pipeline. At the same time, a threefold reduction in the amplitude of pressure fluctuations is achieved. Installation of a diaphragm design with parameters close to the recommended ones is possible anywhere in the suction line, since the change in amplitude at different pressure from the suction valves does not exceed 5...7 %. When installing a diaphragm with dimensions different from those recommended, it is necessary to install it closer to the suction valve.

A methodology for designing biogas pipelines

Dependence on fossil fuels has heightened global energy security issues. Anaerobic digestion (AD) is a technology that can produce biogas to reduce fossil fuel consumption. Transportation of biogas to end users may be achieved using low pressure biogas pipelines. A methodology containing two heuristics (connection based on proximity or output flowrate) is developed to optimise biogas pipeline layouts. A case study of pipeline networks serving up to 10 AD plants and 1 biogas end user is presented. A road network minimum spanning tree (MST) connecting 10 AD plants to the biogas end user is calculated to cost 26% more than a Steiner MST. Multi-criteria decision analysis (MCDA) is used to rank biogas pipeline layouts considering pipeline material cost and biogas flow-rate to the end user. In this analysis, Steiner MSTs always outperform road network MSTs, except when pipeline material cost is disregarded. Scenarios that connected via the proximity heuristic almost always outperformed those which connected via the output heuristic.

Underground Logistics Network Design for Large-Scale Municipal Solid Waste Collection: A Case Study of Nanjing, China

The challenges arising from the management of municipal solid waste (MSW) have a profound impact on the sustainable development of urban areas. As a sustainable solution, the transportation of MSW underground offers the potential to alleviate traffic congestion and reduce environmental pollution. In this study, we propose the implementation of a large-scale underground waste collection system (UWCS). To begin, a comprehensive operational process for the UWCS is designed based on an intelligent technology system, including facility operation, processing workflow, and technical parameters. Additionally, network planning methods for the UWCS are presented. A mixed-integer linear programming model is formulated with the objective of minimizing total cost. This model determines the optimal location and allocation of nodes within the network, as well as the pipeline layout and flow direction. Given the computational complexity, a hybrid optimization method, namely the genetic greedy algorithms and genetic variable neighborhood search algorithms (GGA-GVNS), is devised to obtain high-quality solutions for the model. Finally, to validate the efficacy of the proposed method, a simulation is conducted in the central city of Nanjing, China. The results demonstrate that the implementation of the UWCS network in Nanjing’s city center can yield an annual benefit of USD 5.99 million. Moreover, a sensitivity analysis reveals further MSW management-related insights and long-term planning strategies.

Challenges faced by the municipal water works management in improving water supply adequacy and distribution in Bontoc, Philippines

Domestic water is indispensable for daily use, yet its effective management encounters numerous challenges that impact household consumers. This study aims to identify the challenges leading to supply inadequacy and uneven distribution, while proposing interventions to enhance water supply for households. The study employed surveys, interviews, and focus group discussions to gather comprehensive data on domestic water supply issues in rural communities in Bontoc, Philippines. The findings reveal two primary issues in these rural communities: supply inadequacy and unequal distribution. Supply inadequacy is attributed to factors such as wasteful water use, water scarcity during prolonged dry seasons, limited water sources, and population growth. Uneven distribution results from factors like landslides, illegal tapping, irregular water quality, insufficient monitoring of quantity and pressure, and inadequacies in the water distribution network layout. The study suggests several crucial actions for the local government unit (LGU) of Bontoc. These include augmenting water sources, implementing regular water supply monitoring, ensuring timely repairs, replacing old pipes, optimizing distribution pipeline layouts, enhancing water pressure, and rigorously enforcing municipal water ordinances. Furthermore, the study emphasizes the importance of household water management practices, such as responsible consumption, supply conservation, and recycling. The effective implementation of these interventions, through collaboration between the LGU and households, has the potential to ameliorate the constraints in domestic water supply and distribution. This collaborative approach is essential for improving supply management and addressing the current challenges faced by domestic water consumers.

Realization of rule-based automated design for HVAC duct layout

In the traditional process of pipeline design, a designer typically creates a general layout of pipeline based on their experience, and then calculates whether the hydraulic calculation of pipeline meets the requirements. This method of design is both time-consuming and labor-intensive. Furthermore, the results are often suboptimal and prone to errors, which creates a lot of waste of human and material resources. The objective of this paper is to propose a computer-aided method for completely automating the heating, ventilation and air conditioning (HVAC) duct system design process. This method incorporates all the necessary design processes, such as duct selection and hydraulic calculation, and introduces a rule-based divide-and-conquer method to the pipe routing design (PRD). The research assesses the practical effect of this piping design algorithm in a BIM environment using varied building scenarios. The findings show that the proposed method is capable of meeting the design requirements of actual projects. The automatic piping design technique presented in this paper can significantly reduce labor costs associated with HVAC design while eliminating calculation errors and compressing the design timeline for most of the complex projects to within 5 min.

Collaborative optimization design for district distributed energy system based on energy station and pipeline network interactions

District distributed energy systems (DDESs) are widely used worldwide due to their environmentally-friendly and energy-saving characteristics. The strong correlation and coupling of energy stations and pipeline networks lead to difficulties in the collaborative optimization design of the DDES. To minimize the total annual cost of the system, this research proposed a collaborative optimization model to realize the integrated design of the DDES. The energy distance method is combined with the K-means cluster method to solve the problem of locating and sizing energy stations. The pipelines planning algorithm based on “Dijkstra algorithm (DA) + genetic algorithm (GA)” is used to optimize the pipeline layout and diameter simultaneously. The improved DA method continuously updates the cost full adjacency matrix and pipe diameter matrix of each pipe segment by optimizing the access sequence of user nodes, and finally obtains the optimal layout and pipe diameter of the pipe network at the same time. Moreover, this paper reveals the influence factors that should be considered in the planning of DDES, such as the number of energy station and flow velocity. The results indicate that compared to traditional optimization processes, the collaborative method proposed in this paper reduced the total annual cost of the pipeline network by 20.5 %. The improved DA method solves the problem of pipeline sharing while preventing the system from falling into local optima. Moreover, optimizing the number of energy stations and flow velocity can reduce annual cost of pipelines by 0–14 % and 0–20 %, respectively. This study provides theoretical guidance and technical support for researchers in the planning and designing of DDES.

A mixing algorithm of ACO and ABC for solving path planning of mobile robot

Path planning is involved in many applications such as trajectory planning, mobile robotics, pipeline layout, etc. Researchers use artificial intelligence algorithms to solve path planning efficiently, among which the ant colony algorithm (ACO) is one of the common intelligent algorithms to solve path planning problems. However, the traditional ACO has defects such as low early search efficiency and easy to fall into local optimum, while the artificial bee colony algorithm (ABC) has high search efficiency. Therefore, an improved ant colony optimization-artificial bee colony algorithm (IACO-IABC) is proposed in this study. IACO-IABC contains three mechanisms. First, the heuristic mechanism with directional information for the ACO is improved to enhance the efficiency of steering towards the target direction. Secondly, the novel neighborhood search mechanism of the employed bee and the onlooker bee in the ABC is presented to enhance the exploitation of optimal solutions. Then, the path optimization mechanism is introduced further to reduce the number of turn times in the planned path. To verify the performance of the IACO-IABC, a series of experiments are conducted with 10 different maps. The experiments compare nine variants of ACO and eight commonly used intelligent search algorithms, and the results show the advantages of the IACO-IABC in reducing the number of turn times and path lengths and enhancing the convergence speed of the algorithm. Compared to the best results of other algorithms, the average improvement percentages of the proposed algorithm in terms of the path turn times are 375%, 258.33%, 483.33%, 186.67%, 166.77% and 255.33%, further demonstrating the ability of IACO-IABC to obtain high-quality path planning result.

Slurry Discharge Pipeline Damage and Wear Due to Transporting Rock Particles during Slurry Shield Tunneling: A Case Study Based on In Situ Observed Results

Rock particles in excavated materials can damage and wear down slurry discharge pipelines when slurry shield tunneling occurs in a pebble layer and rock ground. This pipeline damage and wear, if not properly dealt with, can lead to a broken-down tunneling machine. Based on a slurry shield tunneling project in China, damage and wear were thoroughly examined. The observed pipeline wear and leaks, transported rock particles, mechanical properties, and flow rate of the carrier slurry were presented. The measured results showed that the wear rates of a straight pipe, a pipe along a curved tunnel, a 60° inclined pipe, and a 90° elbow pipe in pebble ground were approximately 0.71 mm/100 rings, 1 mm/100 rings, 2.14 mm/100 rings, and 4 mm/100 rings, respectively. When the machine drove into rock ground, the wear rates increased by one to two times, which could be attributed to the sharper particle shapes. Countermeasures to address these issues, such as adjusting the pipeline layout, welding reinforcement plates in advance, and preparing additional pipes, were highlighted. The wear rates of different types of pipes, the effectiveness of new pipeline fixing methods, and the probability of pipeline leaks in different strata were discussed in detail.

Application of modular mathematical modeling in intelligent design of 3D digital substation

Abstract The construction of modular digital smart grid, as a result, the complexity of the power grid is increasing and new technologies and schemes are emerging, more sophisticated design means are needed. Therefore, the author puts forward the research on the intelligent design of three-dimensional digital substation. The emergence of 3D design has changed the status quo of difficult collaboration among multiple disciplines under the traditional design mode, and improved the level of substation design from the perspective of life-cycle management. Firstly, the characteristics of digital collaborative design are analyzed, the construction of 3D model library of equipment is explained, and the intelligent auxiliary control system of substation is described, taking a project as an example, after checking the electrification distance, it can be found that the electrification distance between the camera arranged in the 220kV power distribution unit area and the lightning arrester of the outgoing line does not meet the requirements, and the number of equipment is 3, the application of three-dimensional design is described from the aspects of video monitoring system, automatic fire extinguishing system, etc, its application in the front end equipment layout, model retrieval, collision inspection between safety distance and foundation, buried pipe design, material statistics and other dimensions of these systems were shown in detail, the method of 3D design is deeply studied and applied to the practical engineering design of high voltage substation. The space characteristics of 3D design can be used to realize complex underground pipeline layout, cable optimal layout, collision inspection, construction simulation, visual display, etc.