Numerical study of subcooled and saturated flow boiling in the curved and helically  coiled tubes in presence of phase change is one of the challenging area of CFD studies. In this paper, the CFD modeling of the nucleate and convective flow boiling in the small helically coiled tube at low vapor quality (up to the 18.93 percent) region is studied. A proper Eulerian-based mathematical model is used for interphase exchange forces and heat transfer between two phases in CFD modeling using Bulk boiling model. The results show that, the inner and the bottom wall of the helically coiled tube have the lowest and the highest heat transfer coefficient, respectively. The effect of change in coil diameter, helical pitch and tube diameter is investigated on the counters of vapor volume fraction. It is seen that at low vapor quality flows, the heat transfer coefficient is enhanced by decreasing in coil diameter, tube diameter and increasing in coil pitch of helically coiled tube. 

Control of key technological and benchmark flows of polymer fluids poses a number of challenges. Some of them are nowadays under active investigation and rather far from complete under­stan­ding. This review considers such phenomena as both practically important and governed by funda­mental laws of rheology and non-linear fluid mechanics. We observe, shear bands in polymeric and other complex structured fluids (like wormlike micellar solutions or soft glassy materials), birefrigerent strands, peculiarities of stress and pressure losses in fluids moving through com­plex shape domains. These and other processes involve in­ho­mo­geneity, in­stabilities and tran­sient modes creeping in flow fields. In practical aspect this is of interest in such industrial process as polymer flooding for Enhanced Oil Recovery (EOR), where a flow inhomogeneity affects a poly­mer solution injectivity and residual oil saturation. The value of viscoelasticity in the polymer flooding is estimated. The obser­va­tion is con­clu­ded by some new results on relation between polymer concentration in solutions and viscoelastic traits of benchmark flows.

The heat collection evaporator was modeled based on equilibrium homogeneous theory, and the Runge-Kutta calculation method was used to analyze and solve the flow in the heat collection evaporator. The influence of environmental factors such as solar irradiance, ambient temperature and wind speed on the variation of refrigerant pressure in two kinds of heat collecting evaporator was analyzed under the set working conditions. The results show that the solar energy irradiance has a great influence on the pressure drop in the tube of serpentine heat collecting evaporator, and the maximum pressure drop of the refrigerant in the tube is 16.3%, minimum pressure drop is 7.8%. However, it has little influence on the pressure drop of the tube sheet evaporator. The maximum pressure drop in the refrigerant tube of the tube sheet evaporator is 4.8%, minimum pressure drop is 1.8%. When the irradiance reaches 800 W/m², the refrigerant in the serpentine-tube evaporator has been completely vaporized at 6 m, it’s completely vaporized at 3 m.

 This study explores the primary drivers influencing sustainable project management (SPM) practices in the construction industry. This research study seeks to determine whether firms are primarily motivated by external pressures or internal values when embracing SPM practices. In doing so, this study contributes to the ongoing discourse on SPM drivers by considering coercive pressures (CP), ethical responsibility (ER), and green transformational leadership (GTL) as critical enablers facilitating a firm’s adoption of SPM practices. Based on data from 196 project management practitioners in Pakistan, structural equation modeling (PLS-SEM) was employed to test the hypothesized relationships. Results highlight that CP influences the management of sustainability practices in construction projects, signifying firms’ concern for securing legitimacy from various institutional actors. As an ‘intrinsic value’, ER emerges as a significant motivator for ecological stewardship, driven by a genuine commitment to promoting sustainable development. This study also unveils the significant moderating effect of GTL on the association among CP, ER, and SPM. Lastly, the results of IMPA reveal that ER slightly performs better than CP as it helps firms internalize the essence of sustainability. This research study expands our understanding of SPM drivers in construction projects by exploring the differential impact of external pressures and the firm’s intrinsic values. These findings provide valuable insights for policymakers and practitioners, aiding them in promoting SPM to attain sustainable development goals.

The COVID-19 pandemic has brought life changing conditions to families that require coping strategies in order to survive and achieve family well-being. This study aims to analyze differences between single earner and dual earner families during the COVID-19 pandemic and to analyze the factors that influence subjective family well-being. The research design used was a cross sectional study with sample collection through non-probability sampling. Data collection was carried out by filling out questionnaires online. The number of respondents involved in the study was 2084 intact families with children residing in DKI Jakarta, West Java, and Banten Provinces. Reliability and validity tests were conducted. The results of the independent t-test showed that dual-earner families experienced better life changes and a higher level of subjective family well-being than single-earner families and had lower economic pressure and lower economic coping than single earner families. The SEM analysis found that life changes affected economic coping negatively and subjective family well-being positively. Family income influenced economic coping negatively and subjective family well-being positively. Finally, it was found that economic coping had no effect on subjective family well-being.