Objectives
Sponsored Links
This presentation is the property of its rightful owner.
1 / 22

Objectives PowerPoint PPT Presentation


  • 92 Views
  • Uploaded on
  • Presentation posted in: General

Objectives. Propose topics for the final project Learn about VAV systems. Project. Design problem …. Research problem …. Enthalpy wheel . Couple chiller and cooling tower. Cooling tower. T CTS. T CTR. Weather parameters. P. - Find COP for several weather condition .

Download Presentation

Objectives

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Objectives

  • Propose topics for the final project

  • Learn about VAV systems


Project

  • Design problem

    • ….

  • Research problem

    • ….


Enthalpy wheel


Couple chiller and cooling tower

Cooling tower

TCTS

TCTR

Weather

parameters

P

- Find COP

for several weather condition

  • Use nonlinear equation

    solution methods

TCWS

TCWR

Q


HVAC Control

Economizer (fresh air volume flow rate control)

fresh

air

damper

filter

cooling

coil

heating

coil

filter

steam

humidifier

fan

mixing


Mixture 3

DPTSP

Set Point (SP)

Mixture 2

Mixture 1

DBTSP

Sequence of operation(ECJ research facility)

Control logic:

Mixture in zone 1: IF (( TM<TSP) & (DPTM<DPTSP) ) heating and humidifying

Heater control: IF (TSP>TRA) increase heating or IF (TSP<TRA) decrease heating

Humidifier: IF (DPTSP>DPTRA) increase humidifying or IF (DPTSP<DPTRA) decrease humid.

Mixture in zone 2: IF ((TM>TSP) & (DPTM<DPTSP) ) cooling and humidifying

Cool. coil cont.: IF (TSP<TRA) increase cooling or IF (TSP>TRA) decrease cooling

Humidifier: IF (DPTSP>DPTRA) increase humidifying or IF (DPTSP<DPTRA) decrease hum.

Mixture in zone 3: IF ((DPTM>DPTSP) ) cooling/dehumidifying and reheatin

Cool. coil cont.: IF (DPTSP<DPTRA) increase cooling or IF (DPTSP>DPTRA) decrease cooling

Heater control: IF (TSP>TRA) increase heating or IF (TSP<TRA) decrease heating


Fan

Biomedical Engineering (BME) Building

Duct Optimization

Ducts

Supply

Return

In-Take air

Exhaust


  • 3D model – Biomedical Engineering (BME) Building


  • 3D model – Biomedical Engineering (BME) Building


  • 3D model – Biomedical Engineering (BME) Building


Life Cycle Cost Analysis

  • Engineering economics

Option A

Option B


VAV Example

  • One system

  • Multiple Spaces/Zones

    - VAV box for each space/zone

  • http://www.trane.com/commercial/library/vol242/v24b6.asp


VAV System Terms & Equations(you can find them in ASHRAE Standard 62)

  • Fraction of minimum outdoor air in space/zone supply air

    Xi = VOAi / VSAi

  • Critical space

    Space with maximumXi , Z=max(Xi)

  • Fraction of outdoor air in system supply air

    X = sum(VOA ) / sum(VSA)

  • Required Fraction of outdoor air:

    Y=X/(1+X-Z)


Example Solution


Other Issues Related to VAV

  • Fan control

  • Minimum supply air

  • Occupancy sensors


DOAS System

  • www.doas.psu.edu


DOAS with multi-split systems

Fresh air?


DOAS fresh air configurations


DOAS fresh air configurations


Project

Commercial building

  • Zone orientation


Project

  • Cooling and heating load for each zone and whole building:

  • Fresh air requirement based on number of occupants:

  • To provide acceptable IAQ in the building, ventilation

  • system supply minimal amount of

  • fresh air is in all spaces (except plenums)

  • that produce 0.2 ACH.


Cooling load calculation

  • Mostly computer based

  • Handouts for manual calculation

    • http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/heatloss_table_2008.doc

    • http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/ASHRAE_%20Gains_Calculation_Tables.doc

  • The most important issues


  • Login