Piping Layout Research Articles

Parametric Performance Analysis of the Cooling Potential of Earth-to-Air Heat Exchangers in Hot and Humid Climates

Earth-to-air heat exchangers (EAHEs) are widely used to reduce the indoor temperature and associated cooling energy demand of buildings. This study investigated the potential reduction in indoor temperatures via energy-efficient ventilation through EAHEs in an existing architectural campus building (ACB) with an energy-efficient renovated building envelope in the hot and humid climate of Karachi, Pakistan. The building information modeling (BIM) program Autodesk Revit was used to develop a virtual ACB BIM model. An EnergyPlus parametric analysis of the ACB BIM model in DesignBuilder facilitated quantification of the influences of operating parameters such as pipe installation depth and pipe diameter for EAHEs with similar total pipe lengths and air-exchange rates on the performance of the EAHEs during the cooling season. A 3 m deep and 0.1 m diameter pipe layout in open space significantly reduces indoor temperature via a specific duct layout in an exemplary ACB. The results show that a pipe diameter above 0.1 m is unsuitable because of the reduction in convective heat transfer due to the increase in the pipe’s surface area and the decrease in pressure in the pipe. The findings of this study can be used to improve the indoor thermal comfort of buildings in climates with comparable properties.

Enhancing the performance of asymmetric architectures and workload characterization using LSTM learning algorithm

Asymmetric multiple core architectures are becoming increasingly popular because of their QoS, energy efficiency, and high performance. Because of the heterogeneous piping layout and execution procedure, the overall system performance is highly influenced by workload characterization becomes a difficult issue. Recently, it has become vital to create a performance evaluator for faster response FPGA structures. With the embedded computerized visual hardware resources (e.g. GPUs, FPGAs, and multi-core CPUs) and its associated software manages this heterogeneous system design is tough for the researchers. A thorough analysis of the performance of run-time and various embedded kernels' energy efficiencies to assist developers in determining which embedded substrate is best for their project. To solve these challenges, resource-based prediction models are developed for FPGA-SoC relying on the characterization of intellectual workload, and its performance is thoroughly examined. Xilinx FPGA frameworks are used to run a variety of real-time applications that perform workloads depending on projected processing cores. When compared to existing Ml classifiers, this LSTM predictor achieves a mean of 96% of the experimental findings and also improves energy efficiency.

Design of Water Supply Scheme: A Case Study of Nangargaon Village

Abstract: Design of water supply scheme in around Rural Areas. During classify toward fulfil the water command of the constantly rising population, it is necessary toward supply the plenty with consistent capacity of water through the designed system of pipe. intended for this use the particulars provide via the IPH (Irrigation and Public Health Department) department, the common features of the region similar to in order on the chief water basis, population of the region, insist of water, requirement of the pumps, distribution network and water tanks are essential for efficient design of water distribution system. Water distribution system deals with the supplying of potable water for a village which can be useful for both drinking and wholesome purpose. The main stages of distribution system are collection works, transmission works, purification works and distribution works. It includes estimation of future population (population forecasting) by using various methods, layout of pipes and design of valves and joints, finding out the head losses etc

Investigation of flow field and pollutant particle distribution in the aquaculture tank for fish farming based on computational fluid dynamics

Hydrodynamics is important for fish survival in the aquaculture tank systems, as it can directly affect the behaviour of farmed fish and the self-cleaning property of culture tank systems. The present study designs a new tank configuration, rectangular single-side arc angle tanks, to improve the performance of aquaculture vessels. The tank hydrodynamics was investigated by solving the Reynolds-Averaged Navier–Stokes (RANS) equations and combined with the discrete phase model (DPM) model to study particle motion. The velocity at the monitoring point and the discharge rate of particles from the tank were separately measured using Acoustic Doppler Velocimetry and the MATLAB image recognition method to validate the numerical model. We numerically tested the effect of culture tank configurations and the horizontal distance from the inlet pipe to the sidewall on hydrodynamics parameters, including velocity magnitude and uniformity, turbulence region and vortex distribution. Subsequently, to further understand the self-cleaning property of the culture tank systems for settleable particles, 300 cylindrical particles with a uniform size of 2.5 mm are tracked in the Lagrangian frame. Meanwhile, velocity distribution and pressure gradient have been employed to quantitatively evaluate the effects of hydrodynamics on the collection and discharge regularity of particles. Through CFD-assisted design verification, the tank configuration and the position of the inlet pipe layout have a considerable impact on the removal of particles from the tank and the energy to sustain the flow in the tank. Some key findings are found that 1) the hydrodynamics was improved significantly after rounding two right-angle edges in the rectangular culture tank, in which the configuration tanks of η = 0.2 and η = 0.3 could establish the strengthened rotational flow with better uniformity; 2) the inlet pipes proper far from the sidewall can enhance the self-cleaning property of the tank and the inlet pipe layout position of δ = 0.02–0.04 is the preferred interval.

Analysis of Gas Flow Rate and Pressure Loss of Medical Mask Differential Pressure Tester

The objective of this study is to find a suitable method to overcome the pressure loss problem in the gas pipe during the gas exchange detection of medical masks. Based on the European Standards EN 14683, the parameters of a medical mask differential pressure tester were selected, subsequently two schemes of gas pipe layouts were designed, including four kinds of pipe diameter which are 4, 5, 6.5, and 8mm respectively. Lastly, the models of each scheme were established and imported into Fluent, and the relevant parameters were set for simulation. After data analysis, the results showed that among the four different pipe diameters, the pressure loss of 8mm diameter of the pipe was lower in both the schemes, additionally the pressure loss of the second scheme (the gas pipe was short and smooth) was lower under the same pipe diameter. At the flow rate of v = 8L/min, the pressure loss from the inlet to the measurement point is less than 200Pa, and the estimated measurement error is less than 1.5%. In conclusion, shortening the length of the pipe, and increasing the diameter of the pipe can reduce the gas pressure loss, subsequently improve the measurement accuracy of the medical mask differential pressure tester.

Preliminary design method for absorber pipe length of tunnel lining ground heat exchangers based on energy efficiency of heat pump

Many ongoing tunnel projects provide a favorable opportunity for the investigation and application of tunnel lining ground heat exchangers (GHEs). Tunnel lining GHEs can be connected to a heat pump to extract geothermal energy for heating and cooling buildings. Numerous studies have focused on the thermal performance of tunnel lining GHEs; however, the studies on the interaction between heat pumps and tunnel lining GHEs are relatively rare. In this study, a coupled heat transfer model of heat pumps and tunnel lining GHEs was proposed and then calibrated based on in situ test results. The model was used to evaluate the energy efficiency of a heat pump with tunnel lining GHEs under different conditions. The results show that the energy efficiency ratio (EER) increases exponentially with the absorber pipe length and thermal conductivity of the surrounding rock. The EER is governed by the convection heat transfer coefficient, which varies exponentially; meanwhile, the EER decreases approximately linearly with the annual average air temperature in the tunnel. Different types of heat pumps affect the EER significantly, and the EER of a Type-3 heat pump is higher than that of a Type-1 heat pump by 27.1%. Based on the aforementioned results, an empirical formula for the EER and absorber pipe length was established. Moreover, a preliminary design method for the absorber pipe length based on this empirical formula was developed. The method was employed to determine the appropriate absorber pipe length for the tunnel lining GHEs in the Shapu tunnel in Shenzhen, China. Finally, groups of absorber pipe layouts with a pipe spacing of 0.5 m, area of 135 m2, and length of 293.5 m were preliminarily determined.

Effect of core configuration on natural convection and heat transfer in heat pipe cooled micro-MSRs

Heat pipes are used to remove the nuclear heat of liquid fuel salt in heat pipe cooled micro molten salt reactors (micro-MSRs). The natural convection and heat transfer of fuel salt are influenced by the core configuration. This paper used the ANSYS to simulate the natural convection in a horizontal reactor core with heat pipes arranged in triangular and concentric circular layouts of 0° and ±30°, which can obtain the temperature distribution and heat transfer characteristics of the reactor core and optimize the core design. Also, the influence of the number and diameter of heat pipes were analyzed in this paper. It shows that the temperature distribution under tilt conditions in heat pipes with a concentric circular layout is more uniform and stable than that with a triangular layout. Moreover, stronger heat transfer capacity and more uniform temperature distribution were obtained with denser heat pipes under the same cross-sectional area. Therefore, a concentric circular layout of heat pipes should be adopted in designing the heat pipe cooled micro-MSRs.

AR-based automatic pipeline planning coordination for on-site mechanical, electrical and plumbing system conflict resolution

Mechanical, Electrical and Plumbing (MEP) system conflicts are complicated problems given the involved multidisciplinary nature and constraint-bearing coordination. Although Building Information Modeling (BIM) shows benefit to resolving the conflicts before construction, the on-site pipeline inspection and further adjustment are inevitably necessary due to practical issues caused by deviations with plans. Given this, the research aims at developing an on-site pipeline inspection and automatic coordination approach by using Augmented Reality (AR) and a grid-based path-planning algorithm. The approach allows the site practitioners to compare the newly added pipe layout plan with the existing pipelines and re-plan the pipe layout where encountered conflicts, further obtaining a solution without clashes. The method considers MEP system constraints in practice and searches conflict-free pipe layout plans in near real-time. Furthermore, the path coordination process also considers MEP design criteria, including its function, construction, and maintenance. The planned pipe layout is displayed through AR to link the information from the virtual model to the real world. The performance tests are conducted in virtual scenarios with different grid cell sizes and priorities of pipes to evaluate the planning results. The test results show that under room and aisle space scenarios, the implemented approach can obtain path solutions with approximately 10 s, and most of them comply with the pre-defined MEP design requirements. Through this study, automatic pipe planning with constraints is proved to be feasible to provide an effective on-site conflict resolution approach to improve the MEP construction process and future maintenance.

Calibration and analysis of the potable water network in the Al-Yarmouk region employing WaterGEMS and GIS

Abstract Water supply and distribution networks play an important role in our daily activities. They make a substantial contribution to public health by providing potable water for public consumption and non-potable applications such as firefighters and other purposes such as irrigation. This study used ArcMap 10.8 and WaterGEMS CONNECT Edition update 1 version to create a hydraulic network model to simulate the pipes’ network. Detailed network information, including pipe lengths, layouts, and diameters, was given by the Baghdad Water Department. The TUF-2000H Handheld digital ultrasonic flow meter has been used to measure the water flows in the network’s source nodes. In eight junctions, the model was calibrated by measuring the pressures using the Bourdon gauge at selected junctions. The analysis was based on the steady-state time at the average demand. The analysis results showed that the pressures in the network ranged from 8 to 21 m H2O with a correlation coefficient of 0.988, with a noticeable decrease in pressures in the distant pipes from the sources supplying water to the network. The velocity of the main pipes was within acceptable limits 0.5–2 m/s. While for the internal distribution network, it was noticed that there is an increase in velocity for the main pipes due to low consumption in the lateral pipes.

Design of Water Supply Scheme for Rural Area

Design of water supply scheme in around Rural Areas. During classify toward fulfil the water command of the constantly rising population, it is necessary toward supply the plenty with consistent capacity of water through the designed system of pipe. Intended for this use the particulars provide via the IPH (Irrigation and Public Health Department) department, the common features of the region similar to in order on the chief water basis, population of the region, insist of water, requirement of the pumps, distribution network and water tanks are essential for efficient design of water distribution system. Water distribution system deals with the supplying of potable water for a village which can be useful for both drinking and wholesome purpose. The main stages of distribution system are collection works, transmission works, purification works and distribution works. It includes estimation of future population (population forecasting) by using various methods, layout of pipes and design of valves and joints, finding out the head losses etc.

Study on the Uniformity of Secondary Air of a 660 MW Ultra-Supercritical CFB Boiler

Based on the field test of a 600 MW supercritical circulating-fluidized bed boiler, this paper optimizes the secondary air pipe layout scheme of a 660 MW ultra-supercritical circulating fluidized bed boiler with a similar furnace structure and carried out a numerical simulation on its air distribution uniformity. The secondary air box of the 660 MW ultra-supercritical circulating-fluidized bed boiler adopts a variable section design, and the secondary air branch pipe adopts a separate air inlet mode. The experimental results showed that the oxygen concentration was uniform near the rear wall, but all exhibited a “decrease–increase–decrease” profile along the horizontal line, which indicated that the trajectory of the secondary air jet was first in the shape of bending downward and then upward. To achieve a more uniform secondary air distribution for supercritical CFB boilers, further optimization of the layout of the bellows and branch pipes should be considered. Numerical results showed that the deviation rate of the internal and lower secondary air reached 17%, and there was optimization space for the secondary air branch pipe layout of the boiler. Its uniformity can be increased by adding valves and other measures. The velocity deviation of the secondary air of the 660 MW ultra-supercritical circulating-fluidized bed boiler can be within 3% by means of separate air supply and pipe diameter change, and better uniform air supply can be achieved to reduce the speed deviation by adding valves and adjusting the combustion.

Cracking analysis of massive concrete with large-diameter pipes during construction

This paper presented the results of a study on the cracking behavior of early age massive concrete with large-diameter pipes during construction. Material property tests were conducted to identify the time-dependent mechanical properties of the early age concrete made of P.O. 42.5 cement. A full-scale reinforced concrete block of 4.4×4.8×3m with pipes up to 508 mm in diameter was cast and monitored for the development of the temperature and strain of concrete. A three-dimensional FEM model was established based on user defined subroutine for the time-dependent mechanical and creep properties. The FEM model was verified based on the test results and was used for cracking risk analysis of massive concrete with different pipe layouts. It is found that a diameter to edge distance ratio or a diameter to spacing ratio of no more than 1/3 is sufficient to prevent additional cracking risk of concrete due to the presence of pipes.

Temperature Field of Artificially Frozen Gravel Formation and Optimization of Freezing Pipe Layout Parameters under Seepage Flow

An artificial ground freezing method is often applied to highly permeable gravel formations. Seepage flow increases energy consumption and engineering accidents under this condition. Based on the physical modeling tests, the numerical simulations were conducted. The physical modeling test examined the development of the temperature and frozen wall. Numerical modeling integrated with the ACO algorithm was established to optimize the layout parameters of the freezing pipes. The results indicate that the flowing water prolongs the closure time of the frozen wall. Meanwhile, the total thickness of the frozen wall is also reduced by the flowing water. There are significant differences in the development rates of the frozen wall in different zones. The thickness of the entire frozen wall is nonuniform owing to the seepage flow. Following optimization using the proposed algorithm, the closure time was shortened from 82.4 d to 56.9 d for the frozen wall. Moreover, the freezing efficiency increased by 30.95% after optimization, and consequently, the entire frozen wall was more uniform with a nonweak zone. A case study showed that this optimization system is an effective method for artificial ground freezing operations in geotechnical engineering.

Welding procedure qualification record (WPQR) for welds fabricated at proximity

Maintaining the minimum allowable distance between proximity welds has always been considered a subject of debate among design engineers, welding engineers/inspectors and fabricators/engineering contractors. The scattered nature of guidelines available in welding codes and standards for maintaining the minimum allowable distance poses a significant challenge in the welding procedure and inspection criteria development process. This is especially critical for complex welded joints on submerged sections of offshore structures, in compact layouts/branched connections of topside piping components, and on topside structural joints (depending on the complexity). This manuscript presents the findings of an experimental study that was performed by fabricating two girth welds at proximity on an S355 steel tubular section with diameter of 219.1 mm and thickness of 8.18 mm. Proximity girth welds were fabricated on S355 tubular sections at three different distances between their weld toes, 5, 10, and 15 mm, respectively, using two different welding procedures. Welding procedure qualification record (WPQR) was performed, and all prescribed mechanical tests were recorded as per NORSOK M-101, a structural steel fabrication code. Although all results from the mechanical test met the minimum specified values as defined in the NORSOK code, the research findings revealed a noticeable difference in Charpy and hardness values for proximity region between adjacent welds. Considerable changes in final microstructure morphology were observed between proximity welds due to varying thermal cycles. These observations can form the basis for the future welding procedure qualification of critical welded joints, especially for proximity welds on critical welded joints of offshore structures and welds fabricated during replacement/repair procedures in compact piping layouts.

Study on heat transfer characteristics of the deep-buried ground heat exchanger under different multi-pipe layouts

The pipe group layout and buried pipe spacing in large-scale applications are of great significance for guiding the design of pipe group systems and improving the utilization potential of regional geothermal resources. This work takes a deep-buried coaxial double-pipe heating project at a depth of 2,539 m in Xi'an as an example. It establishes three-dimensional full-scale numerical models that couple the internal and external heat transfer with a multi-pipe system based on the measured ground temperature distribution, ground thermophysical parameters, and an in-situ experiment. The multi-pipe models are divided into two categories based on the pipe layout's minimum basic unit: the straight-line and the equilateral triangle models. Both model categories contain three independent deep-buried coaxial double-pipes, and each model involves four spacings of buried pipes (5 m, 10 m, 15 m, and 20 m). Based on the established models, the heat transfer characteristics of buried pipes under different pipe layouts and buried pipe spacing are studied, and the influences of ground thermal conductivity on the heat transfer in multiple pipes are discussed. Consequently, this study provides a scientific reference for the design of pipe groups for large-scale utilization of geothermal energy in medium-deep layers.

Numerical Investigation on Energy Efficiency of Heat Pump with Tunnel Lining Ground Heat Exchangers under Building Cooling

For mountain tunnels, ground heat exchangers can be integrated into the tunnel lining to extract geothermal energy for building heating and cooling via a heat pump. In recent decades, many researchers only focused on the thermal performance of tunnel lining Ground Heat Exchangers (GHEs), ignoring the energy efficiency of the heat pump. A numerical model combining the tunnel lining GHEs and heat pump was established to investigate the energy efficiency of the heat pump. The inlet temperature of an absorber pipe was coupled with the cooling load of GHEs in the numerical model, and the numerical results were calibrated using the in situ test data. The energy efficiency ratio (EER) of the heat pump was calculated based on the correlation of the outlet temperature and EER. The heat pump energy efficiencies under different pipe layout types, pipe pitches and pipe lengths were evaluated. The coupling effect of ventilation and groundwater flow on the energy efficiency of heat pump was investigated. The results demonstrate that (i) the absorber pipes arranged along the axial direction of the tunnel have a greater EER than those arranged along the cross direction; (ii) the EER increases exponentially with increasing absorber pipe pitch and length (the influence of the pipe pitch and length on the growth rate of EER fades gradually as wind speed and groundwater flow rate increase); (iii) the influence of groundwater conditions on the energy efficiency of heat pumps is more obvious compared with ventilation conditions. Moreover, abundant groundwater may lead to a negative effect of ventilation on the heat pump energy efficiency. Hence, the coupling effect of ventilation and groundwater flow needs to be considered for the tunnel lining GHEs design.

Considerations and complications with "first principles" dynamic modelling of industrial compressors

Readily available processing hardware and "off-the-shelf" (OTS) simulation software has made "high fidelity" first principles models of both steady and transient states, for both axial and centrifugal industrial compressors, relatively easy to construct. These high-fidelity models are finding their way into "real-time. digital twin" performance monitors, front-end engineering design, and post-design – pre-construction compressor performance evaluation. The compressor models are useful for reliably demonstrating the compressor and – to some degree, based on the complexity of the model – process response to various operating conditions. Once the model is constructed, it is trivial to run a "what-if" analysis of compressor performance to answer questions related to (a) recommendations or validation of the recycle/vent valve size and actuation speed, (b) general piping layout and sizing around the compressor, (c) and hot gas bypass requirements, to name a few. This paper takes a practical approach in discussing the compressor and process parameters necessary for building these dynamic "high-fidelity" industrial-compressor models. We identify compressor inputs and compressor responses that are faithfully modeled by first-principle equations available in the simulation software and those that typically require a compromise between an "ab initio" and data-fitting approximation. We discuss the simulation's tendency to overstate pressure excursions during surge events and understate the compressor operation in the "stonewall" region. We also discuss using the simulator software's compressor-stage enthalpy calculations to predict and quantify the compressor train reverse rotation. We use our broad experience and understanding of the compressor operation and simulation and our experience with the AVEVA™ Dynamic-Simulation "OTS" simulation software as the basis for this discussion.

A mixed-integer linear programming formulation for the modular layout of three-dimensional connected systems

Given the considerable complexity of process plants, there has been a great deal of research focused on aiding the design of plant layout through mathematical optimisation, i.e. optimising the positioning of the equipment in the plant for space and cost efficiency. Recently, the use of modular approaches within the construction industry, whereby work is performed off-site before being assembled on-site, has become a popular and powerful way of reducing build schedules and costs. Modular approaches have many other real applications where items must be packed to minimise the connections between them (e.g. piping, wiring, modular office and factory layouts) and consider the modular layout of the system.In this paper, we provide a formulation of the problem that, in addition to the standard layout problem, considers a modular block layout to allow modular construction and transportation of the plant. The problem is represented as a directed network, with the aim to pack the items into predefined containers and minimise the rectilinear distance between the connected items. We propose mixed-integer linear programming (MILP) models for the 2-dimensional and 3-dimensional problems and solve them using the state-of-the-art mathematical programming solver, Gurobi. Because of the combinatorial nature of the problem, solutions involving a large number of items may not converge and a suboptimal solution must be considered. However, our results suggest that even in the case of optimising a large number of items, the suboptimal solutions found after a reasonable number of iterations where deemed, by a domain expert, to be a good enough starting point to continue the design process, especially in the early concept phase.

Deicing efficiency and snow melting on roof through heat exchange pipe

The energy pile can support the load of upper buildings and exploit the shallow geothermal energy by embedding the traditional ground-source heat pump in the pile foundation of buildings. The steel roof has a large span and poor load-bearing capacity, and it is easy to collapse in the ice and snow weather. Based on the model test and the numerical model, the differences of deicing efficiency on roof through heat exchange pipe under different heat exchange pipe materials, position of pipe layout and pipe spacing on the roof panel, etc. were analyzed in this paper, Results showed that, when the heat exchange pipes were arranged above the panel, the ice melting time was about 2 / 3 of that when heat exchange pipes were arranged under the panel; The shorter the pipe spacing and the denser the pipe arrangement, the faster the ice melting rate.

Strategy of subsurface pipe drainage system to alleviate soil salinization based on the DRAINMOD model*

AbstractTo investigate the dynamics and influencing factors of water and salt in subsurface pipe drainage (SPD) systems, three field experiments (denoted as E0.8, E1.1, and E1.4) with different drainage pipe depths (80, 110, and 140 cm, respectively) were conducted in saline farmlands in the Xinjiang Autonomous Region, China. The cumulative water drainage and salt discharge were used to calibrate and validate the DRAINMOD model for simulating water and salt movements in SPD systems. Two indices, the effective leaching water amount (We) and the ratio of the salt discharge rate to the soil desalination rate (Rs/N), combined with the water drainage rate (Rw) and salt discharge rate (Rs), were used to evaluate the effects of salt discharge under different pipe layouts. The experimental results showed that water drainage only started when groundwater completely submerged the subsurface pipes. Furthermore, Rs and Rs/N increased with decreasing burial depth, while the total salt discharge decreased and Rw increased with We. The relationship among We, the burial depth of the subsurface pipe (B), the groundwater table (G), and the Rw or Rs/N of SPD was quantified under different soil textures. In addition, quantitative formulas for determining the water and salt discharge characteristics of SPD were also established.