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The purpose of the present work is to investigate the hydrodynamic and thermal performance of a thermal storage based on the numerical and experimental approaches using the lattice Boltzmann method and the experimental observation on the thermo-physical properties of the operating fluid.

For this purpose, the Al₂O₃ nanoparticle is added to the lubricant with four nanoparticle concentrations, including 0.1, 0.2, 0.4 and 0.6Vol.%. After preparing the nanolubricant samples, the thermal conductivity and dynamic viscosity of nanolubricant are measured using thermal analyzer and viscometer, respectively. Finally, the extracted data are used in the numerical simulation using provided correlations. In the numerical process, the lattice Boltzmann equations based on Bhatnagar–Gross Krook model are used. Also, some modifications are applied to treat with the complex boundary conditions. In addition, the second law analysis is used based on the local and total views.

Different types of results are reported, including the flow structure, temperature distribution, contours of local entropy generation, value of average Nusselt number, value of entropy generation and value of Bejan number.

The originality of this work is combining a modern numerical methodology with experimental data to simulate the convective flow for an industrial application.

This paper aims to investigate the free convection, heat transfer and entropy generation numerically and experientially. A numerical/experimental investigation is carried out to investigate the free convection hydrodynamically/thermally and entropy generation.

The coupled lattice Boltzmann method is used as a numerical approach which keeps the significant advantages of standard lattice Boltzmann method with better numerical stability. On the other hand, the thermal conductivity and dynamic viscosity are measured using modern devices in the laboratory.

Some correlations based on the temperature at different nanofluid concentration are derived and used in the numerical simulations. In this regard, the results will be accurate with respect to using theoretical properties of nanofluid, and close agreements will be detected between present results and the previous numerical and experimental works. The numerical investigation is done under the effect of Rayleigh number (103 < Ra < 106), volume concentration of nanofluid (?? = 0.5, 1, 1.5, 2, 2.5 and 3%) and thermal configuration of the cavity (Cases A, B, C and D).

The originality of the present work lies in coupling of the lattice Boltzmann method with experimental observations to analyse the free convection in a cavity.

The purpose of this study is to examine the prevalence and association among school refusal behavior, self-esteem, parental school involvement and aggression in punctual and truant school-going adolescents.

A purposive sampling technique and cross-sectional design were used in the current study. Participants comprised three heterogeneous sub-groups: school truant students, park truant students and punctual students.

This study’s findings indicated that father and mother’s school involvement was related to more elevated level of self-esteem for school truant students. Results also indicated that male truant students had more significant probability to school refusal behavior and physical aggression as compared to female truant students. Moreover, results revealed that physical aggression fully mediated among mother’s school involvement, academic self and school refusal behavior in punctual students and school truant students.

There is more need to develop indigenous school-based preventions and interventions aimed at decreasing school truancy in Pakistani context by tackling the predisposing vulnerable factors and supporting and encouraging the protective family and internal factors.

Analysis of relationship between energy and growth offers the sustainable energy pathway for a country’s sustainable economic development. This study aims to focus on the evaluation of the Pakistan’s energy system using long-run energy alternative planning (LEAP) modeling framework through different growth scenarios.

Principal component analysis has been adopted for indicators index formation. Study period of 1980 to 2030 is covered by forward and backward simulations in LEAP software.

The study reveals that current energy policy does not have the potential to lead the country toward a desired goal of economic sustainability.

In falling off scenario, negative growth rate (-5 per cent) assumption is also debatable; LEAP shows an error in the analysis and takes the last positive available value for any further analysis as a default. This case could have been simply omitted from results but for research contribution, the computations for this case are also reported.

Long-range energy alternative planning model has been applied to answer the corresponding question for simulation period of 1980 to 2030 to better compare the past trend and future expectations. Critical analysis of four selected scenarios (BAU, moderate, advanced and falling off) indicate that energy policy of Pakistan is poorly managed to maintain energy system’s effectiveness.

As far as statistical difference is concerned, early years have more fluctuation; however, from 2009, curve flattens for energy consumption and energy demand. The increasing demand of energy impacts the society and hence disturbs all sectors.

Policymakers have been so dragged off from the main route to sustainability, despite all odds there is a huge unexplored potential in the country for use to move in step with the world for a better tomorrow. The study educates the policymakers to comprehend the future energy scenarios and make rational decisions based on the study outcomes.

This study aims to validate the royalty rate measurement scale by using rigorous scale validation procedures.

Evaluation of reliability and validity of the measures of royalty rate was performed through confirmatory factor analysis (CFA) using SPSS version 25 and PLS-SEM version 3.8.

The results provide evidence that the royalty rate measurement scale has achieved reliability and validity criteria.

Consequently, policymakers, practitioners and researchers can adopt this scale to assess the royalty rate in other energy sectors where royalty arrangements exist in different jurisdictions across the globe.

The practical contributions of the study are threefold. First, the validated scale presented in Table IV can serve as a checklist for oil and gas producing countries while assessing the stringiness or otherwise of their royalty rates. Second, the validated scale can be used to assess the perception of oil and gas companies with regards to the royalty rate as whether the rate is too high and worrisome or is acceptable. Finally, it could also be used to assess the role of regulatory bodies in assessing royalty rates while dealing with multinational and local oil companies. Eventually, the scale can assist policymakers across the globe to adapt in investment decision-making, particularly regarding royalty arrangement.

This study undoubtedly builds the existing literature and contributes to the subject area; by implication, the validated scale will assist host oil and gas countries with stringent royalty rate to revise the royalty policy in such a way to ensure neutrality, thereby not chasing away the current investors or discouraging prospective ones from investing in their oil and gas industry.