Fundamentals & Engineering
Pump Construction (Part1)
In 1689 the physicist Denis Papin invented the centrifugal pump and today this kind of pump is the most used around the world. The centrifugal pump is built on a simple principle: Liquid is led to the impeller hub and by means of the centrifugal force it is flung towards the periphery of the impellers. The construction is fairly inexpensive, robust and simple and its high speed makes it possible to connect the pump directly to an asynchronous motor.
Expansion Valves Selection
The expansion valve regulates the amount of compressed liquid refrigerant moving into the evaporator. It removes pressure from the liquid refrigerant to allow expansion or change of state from a liquid to a gas in the evaporator. In order to properly select Expansion Valves one should pay attention to the items that we mention in this post.
Water Tube Versus Fire Tube Boilers
Water tube boilers and fire tube boilers are two different types of steam boilers that are commonly used in industrial and commercial applications. Both types of boilers use a system of tubes to generate steam, but they differ in the way that the tubes are arranged and the way that the hot gases from the burner pass through the tubes.
Water Hammer (Part1)
Under unfavorable circumstances, damage due to water hammer may occur in pipelines measuring more than one hundred meters and conveying only several tenths of a liter per second. But even very short, unsupported pipelines in pumping stations can be damaged by resonant vibrations if they are not properly anchored. By contrast, the phenomenon is not very common in building services systems, e.g. in heating and drinking water supply pipelines, which typically are short in length and have a small cross-section.
Refrigeration Formulas and Calculations
These formulas are commonly used in the field of refrigeration and air conditioning to calculate various performance parameters of a refrigeration system such as compression work, compression power, coefficient of performance, net refrigeration effect, capacity, compressor displacement, heat of compression, volumetric efficiency, and compression ratio. These formulas are based on the thermodynamics principles and are generally used to evaluate the performance of the refrigeration system and to optimize its design.
The coefficient of velocity (Cv)
Cv, or coefficient of velocity, is a measure of the flow capacity of a valve. It represents the number of gallons per minute (GPM) of water at 60°F that will flow through a valve with a one-inch opening at a pressure drop of one pound per square inch (PSI). Cv can be calculated using various formulas, such as the one based on water at 60F and one that takes into account the specific gravity of the fluid. Cv is a theoretical value and it may vary depending on the actual conditions of the valve. When selecting a valve for a specific application, it is important to consider the Cv in relation to the flow rate and pressure drop requirements of the system, as well as other factors such as ease of maintenance, cost, and safety.
Pipe Insulation Guideline
Pipe insulation is crucial for maintaining energy efficiency, temperature control, condensation control, noise reduction, and safety. ASHRAE provides specific thickness recommendations for different pipe sizes and temperature ranges in its standard 90.1. When selecting pipe insulation based on ASHRAE standards, it’s important to consider the temperature, pipe size, environmental considerations, fire resistance, and energy efficiency.
Refrigerant Piping – part2
In this post, we will be continuing our comprehensive training on how to size refrigerant piping. We will cover all the important aspects of this process, including determining the pipe size, pressure drop, and other factors. We will also discuss topics such as sizing refrigerant lines, equivalent length for refrigerant lines, and how to determine equivalent length. With this training, you will have the knowledge and confidence to size refrigerant piping accurately and correctly in any situation.
Standards & Compliance
HVAC Load Estimation: Internal Heat Gain from Infrastructure Components (Pipes, Ducts, Tanks, AC Motors)
Complete guide to internal heat gain from HVAC infrastructure components including pipes, ducts, tanks, and motors using Carrier standards for accurate load estimation and system design.
HVAC Load Estimation: Internal Heat Gain from Equipment and Appliances
Complete guide to internal heat gain from equipment and appliances in HVAC load estimation using ASHRAE, CIBSE, and Carrier standards for accurate system sizing and equipment integration.
HVAC Load Estimation: Internal Heat Gain from Lighting
Complete guide to internal heat gain from lighting systems in HVAC load estimation using ASHRAE, CIBSE, and Carrier standards for accurate system sizing and lighting-HVAC integration.
HVAC Load Estimation: Glazing U-Values and Shading Coefficient (SC) Values
Complete guide to glazing U-values and shading coefficients for HVAC load estimation using ASHRAE, CIBSE, and Carrier standards for accurate fenestration thermal and solar analysis.
HVAC Load Estimation: Construction U-Values for Walls, Roofs, and Partitions
Complete guide to construction U-values for walls, roofs, and partitions in HVAC load estimation using ASHRAE, CIBSE, and Carrier standards for accurate thermal analysis.
HVAC Psychrometric Processes: Charts, Calculations, and Air Treatment Applications
Complete guide to psychrometric processes in HVAC design covering sensible/latent cooling, heating, humidification, dehumidification, and evaporative cooling using ASHRAE and CIBSE standards.
HVAC Cooling and Heating Load Estimation: Outdoor Conditions and Climate Data
Comprehensive guide to outdoor climate data for HVAC load estimation using ASHRAE, CIBSE, and Carrier standards. Essential weather parameters for accurate system sizing and energy analysis.
HVAC System Selection and Design Strategy: Professional Standards and Guidelines
Comprehensive guide to HVAC system selection and design strategy using ASHRAE, SMACNA, and Carrier standards. Learn professional methodologies for optimal system selection and performance optimization.
HVAC Design Equations: Air, Fan, Pump, and Hydronic System Calculations
Comprehensive guide to essential HVAC design equations covering air, fan, pump, and hydronic system calculations. Reference standards from SMACNA, ASHRAE, and Carrier for professional engineering applications.
Digital Tools & Resources
Psychrometric Programming Functions
ibrary of psychrometric functions to calculate thermodynamic properties of air for Python, C, C#, Fortran, JavaScript and VBA/Excel
Carrier Hap Software
Carrier’s Hourly Analysis Program is two powerful tools in one package – versatile features for designing HVAC systems for commercial buildings AND powerful energy analysis capabilities for comparing energy consumption and operating costs of design alternatives.
Trace 700 Software
TRACE 700 enables building designers to optimize the building, system and equipment designs on the basis of energy utilization and life-cycle cost. The Trane software for TRACE 700 facilitates analysis of the energy and economic effects of virtually any chiller plant configuration by allowing users to manipulate a wide range of variables and create a profile of their specific building.
Download EVAP-COND 5.0: The Ultimate Heat Exchanger Simulation Tool for HVAC Engineers
Whether you’re designing a new heat exchanger, optimizing an existing system, or researching alternative refrigerants, EVAP-COND provides the detailed analysis capabilities needed to make informed decisions. I encourage all HVAC engineers and researchers to explore this powerful simulation tool and experience firsthand how it can transform your approach to heat exchanger design.
Heat Transfer Textbook Download
The book is meant for juniors, seniors, and first-year graduate students. And to those who choose to learn the subject on their own, and to practicing engineers who use it as a reference. Whether one studies alone or with a class, learning means posing, then answering, one’s own questions.