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"Sebuah teknologi baru bernama pondasi geothermal, integrasi dari pipa penukar panas dengan pondasi tiang beton, adalah sebuah solusi inovatif untuk sistem pemanas bangunan yang mendukung pembangunan energi berkelanjutan. Pondasi geothermal menggunakan energy geothermal dangkal secara langsung dari tanah dan bekerja dengan prinsip energi transfer untuk memproduksi panas yang dibutuhkan oleh bangunan. Pondasi ini bertujuan untuk menghangatkan bangunan selama musim dingin dan mengembalikan energy panas ke dalam tanah selama musim panas. Tesis ini menyajikan studi literatur mengenai mekanisme kompleksitas transfer panas yang terdiri dari kopling termo-hidro-mekanis kemudian menjabarkannya dalam penurunan persamaan konservasi energi. Permasalahan timbul dalam sistem pengoperasian pondasi geothermal yang berbeda setiap musimnya, pondasi geothermal ini dibebani oleh kontraksi termal dan dilatasi termal secara bergantian sehingga mengancam kekuatan mekanis struktur pondasi tersebut, terutama di bagian interface tanah-pondasi. Untuk mengamati perngaruh difusi termal pada kekuatan mekanis pondasi, simulasi numerik pada satu pondasi geothermal di tanah homogen dilakukan dengan menggunakan finite difference code. Batasan studi ini terletak pada pengamatan area difusi termal dalam tanah dan pengaruh dilatasi termal pada pondasi dalam pembebanan termal monoton. Hasil studi diperoleh bahwa area difusi termal yang terpengaruhi mencapai luas 30xdiameter tiang pondasi dan bahwa pembebanan termal monoton hanya memberikan ±1 kPa tegangan termal. Kekuatan mekanis pondas geothermal menjadi suatu permasalahan besar ketika pondasi ini dibebani oleh pembebanan termal siklis sesuai musim.

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A new technology called energy piles, an integration of heat exchanger pipes with concrete piles foundations, is an innovative solution of thermal building system to support energy sustainability development. Energy piles use direct shallow geothermal energy in soil as their heat source and work with the heat transfer principle in order to produce potential heat energy for the building. They intend to warm the building during winter season and to recharge the thermal energy of soil during summer season.

This paper reviews literally complex heat transfer mechanism of system that consists of thermo-hydro-mechanics coupling and divides them into different energy conservations. Nevertheless, due to their seasonal operation time, energy piles are subjected by thermal contraction and dilatation alternately which threaten their mechanical durability, especially at interface soil-pile. Numerical model of a single energy pile in homogenous soil is conducted in this study by using finite difference code. It aims to observe the thermal influence on mechanics behaviour of energy pile.

The main observations in this study are limited on the area of thermal diffusions in soil and thermal dilatations effect under monotonic thermal loading. The result shows that area diffusion influenced is about 30xdiameter of pile and monotonic thermal loading just gives ±1 kPa thermal dilatation stress. Behavior of energy piles is threatened under cyclic thermal loading in their seasonal operation time."

"Thermodynamics of Energy Conversion and Transport (ISBN-13: 9780387989389 and ISBN-10: 0387989382), written by authors Stanislaw Sieniutycz, Alexis De Vos, was published by Springer in 2000. With an overall rating of 4.0 stars, it's a notable title among other Industries (Civil & Environmental, Engineering & Transportation, Engineering Textbooks, Textbooks, Mechanical, Environment, Science & Math, Science & Technology Textbooks, Business, Business & Economics Textbooks) books. You can easily purchase or rent Thermodynamics of Energy Conversion and Transport (Hardcover) from BooksRun, along with many other new and used Industries books and textbooks. And, if you're looking to sell your copy, our current buyback offer is $65.91.DescriptionScientists and engineers are nowadays faced with the problem of optimizing complex systems subject to constraints from, ecology, economics, and thermodynamics. It is chiefly to the last of these that this volume is addressed. Intended for physicists, chemists, and engineers, the book uses examples from solar, thermal, mechanical, chemical, and environmental engineering to focus on the use of thermodynamic criteria for optimizing energy conversion and transmission. The early chapters centre on solar energy conversion, the second section discusses the transfer and conversion of chemical energy, while the concluding chapters deal with geometric methods in thermodynamics."

"Fenomena tegangan lebih peralihan merupakan salah satu permasalahan kualitas daya sistem tenaga listrik karena akan terjadi kenaikan tegangan dengan waktu yang sangat cepat yang menggangu sistem. Tegangan lebih peralihan pada sistem tenaga listrik secara garis besar bersumber dari surja hubung dan surja petir. Surja hubung ini terjadi pada saat pensaklaran beban listrik, sedangkan surja petir berasal dari adanya sambaran petir pada rangkaian listrik. Surja hubung merupakan sumber tegangan lebih peralihan yang paling sering terjadi pada peralatan listrik karena hampir semua peralatan listrik mempunyai saklar untuk menyambung dan memutus beban tersebut dengan sumber listrik. Pada saat terjadi pensaklaran pada suatu rangkaian listrik yang memiliki komponen kapasitor akan terjadi pengisian dan pelepasan energi secara cepat yang menimbulkan perubahan paramater listrik berupa arus dan tegangan yang sangat cepat pada sistem. Komputer merupakan salah satu beban peralatan listrik yang dapat menimbulkan tegangan lebih ketika dilakukan penutupan saklar. Pada komputer terdapat komponen resistor, induktor dan kapasitor yang mempengaruhi bentuk dan besarnya tegangan lebih peralihan yang terjadi. Tegangan lebih peralihan ini juga dilakukan pemodelannya pada beban RLC murni untuk melihat tegangan lebih yang terjadi saat dilakukan pensaklaran terhadap variasi beban resistor, induktor dan kapasitor. Dengan adanya simulasi ini akan digunakan untuk membandingkan tegangan lebih yang terjadi dengan tegangan lebih pada beban komputer.

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Fenomena of transient over voltage is one of power system quality problem because the level of voltage will increase with very fast time that it will bother the system. Transient over voltage in power system sourced from switching surge and lighting surge. Switching surge occured when switching load, meanwhile lighting surge sourced from clap on electric circuit.Switching surge is the most of sourced transient over voltage on electrical equipment because most of them have switch for connected and cut off load from sourced. When swtiching occur on an electric circuit that has capacitor will happen charging and discharging energy fast which create electric paramater transformation very fast such as current and voltage on system. Computer is one of electrical equipment which create over voltage while closing the switch. On a computer, there is resistor component, induktor, and capacitor that affect form and level of transient over voltage that occur. This transient over voltage is modeled with simulation on RLC load to see the over voltage that occured when switching on varity of resistor load, induktor and capacitor. This simulation will be used to compare the over voltage which occured with the over voltage on computer."

"This book presents cutting-edge work on the energy efficiency and environmental sustainability of buildings, examining EU policies, regulations and technologies for complex systems such as passive buildings, sustainable buildings and, as part of the Energy Performance of Building Directive (EPBD), nearly Zero Energy Buildings (nZEB) requirements. It explores a wide range of topics, including indoor environment requirements, building physics, in-situ experiments to determine the thermal properties of buildings, nZEB requirements, building service technology, and methods of evaluating energy efficiency and environmental impacts. It also provides an overview of the best available technologies for nZEB, including those for the rational use of energy, utilization of renewable energy sources, EPBD systems and calculation methods. This book is a valuable resource for students, researchers and practitioners of urban planning, and architecture, civil and mechanical engineering."

"The heat and energy transfer around a cluster of traditional Balinese buildings is extremelycomplicated and difficult to determine by modeling an isolated building (eg. via symmetry conditions).Full scale models of traditional buildings have been investigated by using numerical method based on thefinite element method to assess the facts of roof type on heat and energy transfer. A standard k-e modelis adopted with low values of k and e combined with multi-blocks grids, in order to reduce the over-estimation of the production term of the turbulent kinetic energy in standard k-s turbulence models."

"Omar Abu Mohareb proposes a novel dynamic inductor control (DIC) that can be generally applied to various DC-DC converter types. The aim is to improve the converter efficiency throughout controlling the inductance value at all operating points without consequential complexity or increase in the inductor cost and size. The dynamic inductor control implies the maximum energy transfer (MET) concept to improve the DC-DC converter efficiency and preserve a fast system dynamics against load changes at the same time.ContentsEffects of Varying Inductance Value on Converter Efficiency and PerformanceBoost Battery Charger ModelingDevelopment of Dynamic Inductor Control (DIC) and Maximum Energy Transfer (MET) ConceptsDynamic Inductor Control Concept Simulation and Implementation"