Solar water heating (SWH) systems have a widespread usage and applications in both domestic and industrial sectors. According to Renewable Energy Policy Network data (2010), 70 million houses worldwide were reported to be using SWH systems. Solar water heating is not only environmentally friendly but requires minimal maintenance and operation cost compared to other solar energy applications. SWH systems are cost effective with an attractive payback period of 2–4 years depending on the type and size of the system. Extensive research has been performed to further improve the thermal efficiency of solar water heating. This paper presents a detailed review exclusively on the design aspects of SWH systems. The first part of the paper provides a consolidated summary on the development of various system components that includes the collector, storage tank and heat exchanger. The later part of this paper covers the alternative refrigerant technology and technological advancements in improving the performance as well as the cost effectiveness of the SWH system.

Recent advances in the solar water heating systems: A review

Advancements into the computational studies have increased the development of heat pipe arrangements, displaying multiphase flow regimes and highlighting the broad scope of the respective technology for utilization in passive and active applications. The purpose of this review is to evaluate current heat pipe systems for heat recovery and renewable applications utility. Basic features and limitations are outlined and theoretical comparisons are drawn with respect to the operating temperature profiles for the reviewed industrial systems. Working fluids are compared on the basis of the figure of merit for the range of temperatures. The review established that standard tubular heat pipe systems present the largest operating temperature range in comparison to other systems and therefore offer viable potential for optimization and integration into renewable energy systems.

A review of heat pipe systems for heat recovery and renewable energy applications

Three-dimensional numerical study of heat transfer characteristics of parabolic trough receiver

The solar water heating system (SWHS) is one of the most common application of solar energy utilization system The usage of solar water heating system is not commonly employed throughout the globe, due to its high initial cost The advancement in SWHS will lead to be beneficial over conventional system over the long span of time The eco-friendly nature of such system promotes these systems to be used frequently in both domestic and industrial heating The investigators throughout the globe focusing on technical advancement as well as economic feasibility of SWHS The present study focused on to report such studies, which demonstrates the economic feasibility of SWHS in the long run The payback period of SWHS varies from one origin to other as it depends on numerous factors like price of fossil fuels, rate of subsidy, solar insolation etc Initially the paper reported the basic components of SWHS, and their advancements, further the global scenario of SWHS is discussed, followed by the studies reported on a techno economic analysis of SWHS, which shows that the economic feasibility is equally important as technical feasibility for its implementation The last section inculcates the recent studies on the technical advancement of SWHS and the future research trends of SWHS were discussed

A review on technical improvements, economic feasibility and world scenario of solar water heating system

Presented here is a numerical investigation of the influence of non-uniform soil conditions on a prototype concrete bridge with three bents (four span) where soil beneath bridge bents are varied between stiff sands and soft clay. A series of high-fidelity models of the soil-foundation-structure system were developed and described in some details. Development of a series of high-fidelity models was required to properly simulate seismic wave propagation (frequency Lip to 10Hz) through highly nonlinear, elastic plastic soil, piles and bridge structure. Eight specific cases representing combinations of different soil conditions beneath each Of the bents are simulated. It is shown that variability of soil beneath bridge bents has significant influence on bridge system (soil-foundation-structure) seismic behavior. Results also indicate that free field motions differ quite a bit from what is observed (simulated) under at the base of the bridge columns indicating that use of free field motions as input for only structural models might not be appropriate. In addition to that, it is also shown that usually assumed beneficial effect Of Stiff soils underneath a Structure (bridge) cannot be,generalized and that such stiff soils do not necessarily help seismic performance of structures. Moreover, it is shown that dynamic characteristics of all three components of a triad made Lip of earthquake, soil and structure play crucial role in determining the seismic performance of the infrastructure (bridge) system. Copyright (C) 2009 John Wiley & Sons, Ltd.

Time domain simulation of soil-foundation-structure interaction in non-uniform soils

The ability to work effectively on a team is highly valued by employers, and collaboration among students can lead to intrinsic motivation, increased persistence, and greater transferability of skills. Moreover, innovation often arises from multidisciplinary teamwork. The influence of personality and ability on undergraduate teamwork and performance is not comprehensively understood. An investigation was undertaken to explore correlations between team outcomes, personality measures and ability in an undergraduate population. Team outcomes included various self-, peer- and instructor ratings of skills, performance, and experience. Personality measures and ability involved the Five-Factor Model personality traits and GPA. Personality, GPA, and teamwork survey data, as well as instructor evaluations were collected from upper division team project courses in engineering, business, political science, and industrial design at a large public university. Characteristics of a multidisciplinary student team project were briefly examined. Personality, in terms of extraversion scores, was positively correlated with instructors’ assessment of team performance in terms of oral and written presentation scores, which is consistent with prior research. Other correlations to instructor-, students’ self- and peer-ratings were revealed and merit further study. The findings in this study can be used to understand important influences on successful teamwork, teamwork instruction and intervention and to understand the design of effective curricula in this area moving forward.

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The influence of personality and ability on undergraduate teamwork and team performance

Temperature stratification from thermal diodes in solar hot water storage tank

A pilot implementation of an experimental interdisciplinary course on climate solutions was undertaken at San Jose State University inthe fall semester of 2008. The course, co-taught by seven faculty members from six colleges, was approved for a general educationrequirement and was open to upperclass students campus-wide. A course with such a breadth of topics and range of student backgroundswas the first of its kind here. The lessons learned from the pilot effort were assessed from student, faculty, and administrativeperspectives. The educational benefits to students from the interdisciplinary format were found to be substantial, in addition to facultydevelopment. However, challenges associated with team-teaching were also encountered and must be overcome for the long-term viabilityof the course. The experimental course was approved as a permanent course starting in the fall semester of 2009 based on the pilot effort,and plays a role in the College of Engineering’s recent initiatives in sustainability in addition to campus-wide general education.

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Pilot implementation of an interdisciplinary course on climate solutions

The steady-state thermal resistance of a small heat source applied to a diamond heat spreader attached to a larger substrate with Newtonian cooling on the opposite side was evaluated using numerical simulation The substrate with Newtonian cooling models a range of convection-cooled designs, such as a heat sink base with a finned surface or the base of a cold plate with liquid cooling The objective of this work is to quantify the thermal performance of the modeled system as a function of the diamond heat spreader size and properties The resulting maximum thermal resistance as a function of diamond spreader thickness, lateral dimension, and conductivity are presented, as well as some guidelines for effective thermal design In addition, a range of convection conditions typical for these applications are examined Synthetic diamond is still an expensive material, ranging from $1 to $20 per square millimeter in the lateral plane The price increases sharply with conductivity, thickness, and lateral dimension, all of which increase thermal performance of the diamond spreader For this reason, the cost per thermal performance is a distinctly different optimization problem from the thermal performance alone The results of this optimization are presented for a Biot number typical for forced convection through a finned surface using direct air cooling

Performance-cost optimization of a diamond heat spreader

The continuous, one-dimensional kernel function in a rectangular duct subject to forced convection with air was experimentally estimated using liquid crystal thermography techniques. Analytical relationships between the kernel function for internal flow and the temperature distribution resulting from a known heat flux distribution were manipulated to accomplish this objective. The kernel function in the hydrodynamically fully developed region was found to be proportional to the streamwise temperature gradient resulting from a constant heat flux surface. In the hydrodynamic entry region of the rectangular duct, a model for the kernel function was proposed and used in its experimental determination. The kernel functions obtained by the present work were shown to be capable of predicting the highly nonuniform surface temperature rise above the inlet temperature resulting from an arbitrary heat flux distribution to within the experimental uncertainty. This is better than the prediction obtained using the analytically derived kernel function for turbulent flow between parallel plates, and the prediction obtained using the conventional heat transfer coefficient for constant heat flux boundary conditions. The latter prediction fails to capture both the quantitative and qualitative nature of the problem. The results of this work are relevant to applications involving the thermal management of nonuniform temperature surfaces subject to internal convection with air, such as board-level electronics cooling. Reynolds numbers in the turbulent and transition range were examined.

Jinny Rhee

Papers

The influence of personality and ability on undergraduate teamwork and team performance

Temperature stratification from thermal diodes in solar hot water storage tank

Pilot implementation of an interdisciplinary course on climate solutions

Performance-cost optimization of a diamond heat spreader

Experimental Estimate of the Continuous One-Dimensional Kernel Function in a Rectangular Duct With Forced Convection