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The University of Texas at Austin Spring 2011 CAEE Department, Architectural Engineering Program Course : HVAC Design ARE 346P/CE 389H/ARE 389H Instructor : Dr. Novoselac, Atila ECJ, 5.422 Office (512) 475-8175 e-mail: atila@mail.utexas.edu
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The University of Texas at Austin Spring 2011 CAEE Department, Architectural Engineering Program Course: HVAC Design ARE 346P/CE 389H/ARE 389H Instructor: Dr. Novoselac, Atila ECJ, 5.422 Office (512) 475-8175 e-mail: atila@mail.utexas.edu http://www.ce.utexas.edu/prof/Novoselac Office Hours: Tuesday and Thursday 11:00 – 12:00 p.m.
Objectives • Introduce course syllabus and establish ground rules • Describe class content • Address any of your concerns
Introduce yourself • Who are you? • Grad/undergrad? • Department? • Your professional interest?
HVAC systems • Systems that: • Cost very much (residential 10-20% , commercial 20-50% of total cost) • Uses the most energy • Most strongly influences our comfort • Has great potential to improve/degrade our health • No longer taught in ME (at UT) • Very high demand for graduates
Motivation for studying HVAC systems • Responsible for ~40% of energy consumption • ~90% of our time is spent indoors • HVAC systems are a central part of every building
Prerequisites (not strictly enforced) • Building Environmental Systems • Familiarity with HVAC • Thermodynamics • Psychrometrics, phase change, properties • Fluid Mechanics • Flow in pipes and ducts, non-dimensional numbers • Heat Transfer • Conduction, convection, radiation
Course Objectives • Apply fundamental physical principles to HVAC design • Describe and size each component in an HVAC system • Design HVAC systems based on manufacturer’s datasheets • Contrast residential systems with commercial systems and use appropriate design techniques for each type of system • Solve HVAC design problems with high-quality references
Course Topics • Background, Introduction and Review 2 wks • Heating and Cooling Loads 1 wk • Psychrometrics and mass transfer 1 wk • Air conditioning and refrigerant cycles 2 wks • Chillers and Boilers 1 wk • Coils and heat exchangers 2 wks • Ducts, air, and water systems 2 wks • Large HVAC Systems 2 wk • HVAC Control 2 wk • Final Project, field trip 1 wk • 15 wks
What am I NOT covering? • Detail calculation of Cooling/Heating loads • Human comfort/Indoor air quality • Furnaces and boilers • Absorption cycle refrigeration • Energy generation
This is a skills class • I expect you to come away from this class and be able to understand everything that you see in an HVAC system or know where to go to learn about it. • You will be able to size most HVAC components, design smaller and medium size systems and understand larger systems
Textbook • Kuehn, T.H.; Ramsey, J.W.; Threlkeld, J.L. 1998. Thermal Environmental Engineering (3rd Edition) Prentice Hall ISBN: 0139172203 • First edition was 1962 • Excellent graduate/undergraduate textbook • Thorough, fundamental, many examples • Look forward to your opinion • Other books are optional
Grading • Mid-Term Exam 25% • Project 30% • Homework Assignments 40% • Participation 5% 100% • Homework is a large part of your grade • ~ Weekly assignments, reducing in intensity by the end of semester • 10% penalty per day for late assignments • You are allowed to work together, but each student must prepare their own solution
Project (30%) • Final Project (30%) individual/group • Design HVAC component • Assigned 4/12, due 5/5 • Final project will have written (short) and oral components
Exam (25%) • One open-book midterm exam: • April 12 tentative • 1 or 2 longer problem(s) • Few short answer questions
Participation • My assessment of your participation in the class • 5% of total grade • How to get participation points • Come to class and be on time • Submit all assignments/project on time • Participate in class
My Issues • Please don’t come to my office between 8:30 and 9:30 am on Tuesday and Thursday • Class preparation • Please don’t use e-mail to ask me “content” questions • Call me or come see me • Suggestion are welcome
Course Website • All class information online • http://www.ce.utexas.edu/prof/Novoselac/classes/ARE389H/ • PLEASE LET ME KNOW ABOUT ERRORS
TENTATIVE COURSE SCHEDULE Continues from previous page
Missed Class • Need to miss one classes • Tuesday 02/01 (ASHRAE Meeting) Make-up Class: • Field trip
The Big Picture • HVAC systems need to provide conditioned and acceptable air quality in buildings • Heating, Cooling, Ventilation • Heating, cooling, ventilation loads
Systems: Heating • Make heat (furnace, boiler, solar, etc.) • Distribute heat within building (pipes, ducts, fans, pumps) • Exchange heat with air (coils, strip heat, radiators, convectors, diffusers) • Controls (thermostat, valves, dampers)
Systems: Cooling • Absorb heat from building (evaporator or chilled water coil) • Reject heat to outside (condenser) • Refrigeration cycle components (expansion valve, compressor, concentrator, absorber, refrigerant) • Distribute cooling within building (pipes, ducts, fans, pumps) • Exchange cooling with air (coils, radiant panels, convectors, diffusers) • Controls (thermostat, valves, dampers, reheat)
Systems: Ventilation • Fresh air intake (dampers, economizer, heat exchangers, primary treatment) • Air exhaust (dampers, heat exchangers) • Distribute fresh air within building (ducts, fans) • Air treatment (filters, etc.) • Controls (thermostat, CO2 and other occupancy sensors, humidistats, valves, dampers)
Systems: Other • Auxiliary systems (i.e. venting of combustion gasses) • Condensate drainage/return • Dehumidification (desiccant, cooling coil) • Humidification (steam, ultrasonic humidifier) • Energy management systems
Drain Pain • Removes moisture condensed from air stream • Cooling coil • Heat transfer from air to refrigerant • Extended surface coil Condenser Expansion valve Controls Compressor
Heating coil • Heat transfer from fluid to air Heat pump Furnace Boiler Electric resistance Controls
Blower • Overcome pressure drop of system Adds heat to air stream Makes noise Potential hazard Performs differently at different conditions (air flow and pressure drop)
Duct system (piping for hydronic systems) • Distribute conditioned air • Remove air from space Provides ventilation Makes noise Affects comfort Affects indoor air quality
Diffusers • Distribute conditioned air within room Provides ventilation Makes noise Affects comfort Affects indoor air quality
Dampers • Change airflow amounts Controls outside air fraction Affects building security
Filter • Removes pollutants • Protects equipment Imposes substantial pressure drop Requires Maintenance
Controls • Makes everything work Temperature Pressure (drop) Air velocity Volumetric flow Relative humidity Enthalpy Electrical Current Electrical cost Fault detection
Goals of this class • Use thermodynamics, fluid mechanics, heat transfer, control theory, physics, critical analysis to design HVAC systems that work