DEVELOPMENT AND EXPERIMENTAL VALIDATION OF SIMULATION

2,28

MB

OF HYDRONIC SNOW MELTING SYSTEMS FOR BRIDGES

262

stron

6387

ID

Oklahoma State University

2005

rok

TABLE OF CONTENTS

CHAPTER 1. INTRODUCTION.1

CHAPTER 2. LITERATURE REVIEW7

2.1. Modeling Hydronic Snow Melting Systems.7

2.1.1. Steady State Models.8

2.1.2. Transient Models14

2.1.3. Summary.26

2.2. Design of Snow Melting Systems.27

2.2.1. Design Objective27

2.2.2. Determining Heating Capacity of Snow Melting Systems.32

2.2.3. Summary.35

CHAPTER 3. DEFINITION OF THE PROBLEMS AND OBJECTIVES.37

3.1. Modeling Snow Melting on a Hydronically-Heated Slab38

3.2. Simulation of Hydronic Snow Melting Systems39

3.3. Heating Capacity of Hydronic Snow Melting Systems40

CHAPTER 4. DEVELOPMENT AND EXPERIMENTAL VALIDATION OF A NUMERICAL MODEL

FOR HYDRONICALLY-HEATED SLAB IN SNOW MELTING CONDITIONS.41

4.1. Model Development.43

4.1.1. Classification and Definition of Surface Conditions46

4.1.2. Snow Melting Model48

4.1.3. Model Implementation.58

4.2. Experimental Validation.59

4.2.1. Experimental Hydronic Bridge Snow Melting System60

4.2.2. Model Data.61

4.2.3. Validation Results71

4.3. Conclusions.84

CHAPTER 5. SIMULATION OF GSHP BASED HYDRONIC SNOW MELTING SYSTEMS86

5.1. Component Models of the System Simulation.88

5.1.1. Ground Loop Heat Exchanger89

5.1.2. Water-to-water Heat Pump.99

5.1.3. System Controller.101

5.1.4. Circulating Pump103

5.2. Implementation of the System Simulation.104

5.2.1. Overview of HVACSIM+104

5.2.2. Dealing with Discrete Controller108

5.2.3. Decoupling Hydronic and Thermal Calculations.110

5.3. Experimental Validation of System Simulation Results111

5.3.1. Experimental Apparatus.111

5.3.2. Validation Results of Individual Component Models114

5.3.3. Validation Results of System Simulation.124

5.4. Conclusions.144

CHAPTER 6. SIMULATION BASED INVESTIGATION ON THE DESIGN OF HYDRONIC SNOW

MELTING SYSTEMS.147

6.1. ASHRAE Snow-melting Loads148

6.2. Simulation Approach151

6.3. Weather Data153

6.4. Organization and Methodology of Parametric Study.154

6.5. Results and Discussion.158

6.5.1. Idling Time, Heating Capacity, and Snow Melting Performance159

6.5.2. Effects of Pipe Spacing and Bottom Condition163

6.5.3. Effects of Control Strategies165

6.5.4. Effects of Pavement Properties170

6.6. Snow Melting Loads for Ar=0.5.173

6.7. Updated Snow Melting Loads177

6.8. Conclusions.184

CHAPTER 7. CONCLUSIONS AND RECOMMENDATIONS186

BIBLIOGRAPHY.194

APPENDIX A: MODEL DOCUMENTATION207