In recent years, the environmental necessity to replace HFC refrigerants with natural refrigerants like carbon dioxide (CO2) in refrigeration and air-conditioning applications has led to the development of an Ultra High Pressure Tribometer (UHPT) specifically customized for testing in CO2 environment at pressures comparable to those found in compressors up to 13.8 MPa (2000 psi). It was found t...

~bstkzcthe open-ended coaxial probe with lift-off is studied the effects of air gap on dielectric measurements. Also, in using a full-wave inalysis, and an uncertainty analysis is presented. The field equations for the following terminations are worked out: (1) the sample extends to x in the positive axial direction, (2) the sample is backed by a well-characterized material, and (3) the sample ...

3 PREFACE 4 ACKNOWLEDGEMENTS 5 PUBLICATIONS 6 ABBREVIATIONS AND NOMENCLATURE 7 TABLE OF CONTENTS 10 INDEX OF FIGURES 11 INDEX OF TABLES 14 1 INTRODUCTION – BASIC CONCEPTS 15 1.1 GROUND SOURCE HEAT PUMPS 15 1.2 THERMAL PROCESSES IN THE GROUND 18 1.3 SECONDARY WORKING FLUID FLOW 20 1.3.1 Hydrodynamic considerations 21 1.3.2 Thermal considerations 21 1.4 THERMAL RESISTANCES IN BHES 23 1.5 ...

In addition to improving population health, an important goal of health systems is to ensure that the financial burden of paying for health is distributed fairly across households (1). Exploring fairness in financial contribution requires the ability to measure each household’s financial contribution (HFC), defined as the ratio of a household’s health system contributions to its capacity to pay...

Abstract—In present paper, the performance of various alternative refrigerants is compared to find the substitute of R22, the widely used hydrochlorofluorocarbon refrigerant in developing countries. These include the environmentally friendly hydrofluorocarbon (HFC) refrigerants such as R134A, R410A, R407C and M20. In the present study, a steady state thermodynamic model (includes both first and...

The IEEE 802.14 standard committee is currently working on a project to find a costeffective means of providing access to integrated networks for people to enjoy multimedia programs and to work at home. An advanced system based on the CATV system called Hybrid Fiber Coax (HFC) is being studied. Since some properties of the HFC system preclude the possibility of directly using existing medium ac...

The IEEE 802.14 standard committee is currently working on a project to find a cost-effective means of providing access to integrated networks for people to enjoy multimedia programs and to work at home. An advanced system based on the CATV system called Hybrid Fiber Coax is being studied. Since some properties of the HFC system preclude the possibility of directly using existing medium access ...

Title of Document: FLOW AND ATOMIZATION CHARACTERISTICS OF CRYOGENIC FLUID FROM A COAXIAL ROCKET INJECTOR Vivek Gautam, Ph.D., 2007 Directed By: Professor, Ashwani K. Gupta, Department of Mechanical Engineering High thrust-to-weight ratio and consistent performance over a range of operating conditions make cryogenic rocket engines one of the best options for space propulsion. However, future sp...