![]() ![]() If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE. Learn more about the HVACR Training Symposium or buy a virtual ticket today at. Unique duct challenges with inverter-driven systemsĬheck out Joey’s training, social media, and contact information at.Communicating with customers about airflow issues.Learning from other educators as an educator.Joey’s HVAC beginnings in the Navy and current work in education.We can start by looking at things that can improve system performance at the equipment, like filtration we can think of the equipment as the heart and the duct system as arteries (with static pressure as blood pressure), and the equipment also has the biggest pressure drop. Some technicians also aren’t properly trained to position their static pressure probes appropriately to measure total external static pressure, which leads to faulty readings and misinformed diagnoses. Bypass dampers are also commonly misapplied. In many cases, proper duct design would solve problems without the need for balancing dampers. We also need to keep in mind that flex ducts need to be as straight and tight as possible, and it’s usually best if we slightly upsize them (compared to sheet metal).Įven though balancing dampers aim to solve airflow problems, they often lead to other issues when installed and used incorrectly. In residential HVAC, many duct systems aren’t adequately planned out, and the airflow can’t overcome restrictions like filters. In many cases, people focus too heavily on the equipment when diagnosing airflow problems sometimes, the equipment simply can’t perform as it should due to a poorly designed duct system. You can easily access the high quality refrigerant chart by clicking on the refrigerants listed in the table.Joey Henderson joins the podcast to talk about airflow and how we can get air where it needs to go.ĭuct design is one of the subjects that fuel Joey’s passion for HVAC. This article is a continuation of our older article, which was well received by users, so we decided to update the P-H Diagram list and provide you with a more complete list of the world's commercial refrigerants. Also in the superheated region, the constant-entropy lines incline sharply upward, and constant volume lines are flatter. Pressure: bar: Enthalpy: kJ/kg: Temperature ☌: Entropy: kJ/(kgK) Quality/Dryness-Heat Capacity: kJ/(kgK) Ratio Cp/Cv-Density: kg/m3: Dyna. The specific enthalpy of evaporation can be calculated from: he hg - hf (4) where. In two-phase region, the constant temperature lines are horizontal. Adicot's Psychrometric Chart Calculator is a powerful technical tool designed to facilitate the calculation and analysis of various parameters associated with the thermodynamic properties of air. For saturated steam at standard atmosphere - 2) - the specific enthalpy - hg - is 2676 kJ/kg. At higher temperatures, they are curves near the saturated liquid line. The constant-temperature lines are nearly vertical in the sub-cooled liquid region. In the two-phase region, the constant-dryness-fraction quality line subdivides the mixture of vapor and liquid. Ductulator - Hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. The saturated vapor line separates this two-phase region from the superheated vapor. The equation to calculate pressure based on altitude is: P a tm 14.696 1 - 6.8754 x 10(-6) Z5.2559 psia x 2. HVAC design tools include such popular items as the Trane Ductulator, psychrometric charts, and load estimating forms. The saturated liquid line separates the sub-cooled liquid from the two-phase region in which vapor and liquid refrigerants coexist. See also Water - Enthalpy (H) and Entropy (S) for figures and tabulated values at varying temperatures. The Mollier diagram is useful when analyzing the performance of adiabatic steady-flow processes, such as flow in nozzles, diffusers, turbines and compressors. Please allow more processing time for mixed refrigerant. The diagram below can be used to determine enthalpy versus entropy of water and steam. P-h enthalpy diagram consist of following lines:Įnthalpy “ h” is along x-axis and absolute pressure “ p” is along the y-axis, both expressed in logarithmic scale. Online Interactive Pressure-Enthalpy (p-H) and Temperature-Entropy (T-s) diagram Online Interactive p-H and T-s Diagram. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |