Equipaggiamento e sistemi
Thermal Storage (HVAC)
L'energia termica può essere immagazzinata in tre modi principali: – Accumulo sensibile – Accumulo latente – Accumulo termochimico. Inoltre, le due comuni strategie di accumulo termico impiegate sono: – Strategia di livellamento del carico – Strategia di spostamento del carico
Variable Refrigerant Flow (VRF) Benefits
VRF systems are available either as heat pump systems or as heat recovery systems for those applications where simultaneous heating and cooling is required. In addition to providing superior comfort, VRF systems offer design flexibility, energy savings, and cost effective installation. A VRF system offers flexible installation and energy-saving cooling and heating comfort and should be considered as an alternative to traditional systems for those applications where zoning or part load operation is required.
Hydropneumatic Tank Sizing
Hydropneumatic tanks are primarily used in a domestic water system for draw down purposes when the pressure booster system is off on no-flow shutdown (NFSD). The NFSD circuitry turns the lead pump off when there is no demand on the system. While the system is off in this condition, the hydropneumatic tank will satisfy small demands on the system. Without the tank, the booster would restart upon the slightest call for flow such as a single toilet being flushed or even a minute leak in the piping system. Hydropneumatic tank sizing is dependent on two factors: – Length of time you wish the pumps to remain off in a no-flow situation. – The tank location in relation to the pressure booster.
Typical Piping For Steam Heating
The piping and radiator connections shown in this section are diagrammatic and illustrate the proper method of making piping connections in steam heating processes. – Two pipe steam systems radiator connections – Piping connections for unit heaters (steam) – Two pipe– #steam trap installations – Two Pipe Steam Systems Convector Connections – Exposed #Pipe #Coils– Two Pipe Steam – One pipe #steam systems radiator connections – One pipe steam systems #convector connections – One pipe steam systems convector connections
Refrigerant Piping (Part1)
Good piping design results in a balance between the initial cost, pressure drop, and system reliability. The initial cost is impacted by the diameter and layout of the piping. The pressure drop in the piping must be minimized to avoid adversely affecting performance and capacity. Because almost all field-piped systems have compressor oil passing through the refrigeration circuit and back to the compressor, a minimum velocity must be maintained in the piping so that sufficient oil is returned to the compressor sump at full and part load conditions. Several HVAC systems require field refrigeration piping to be designed and installed on-site. Examples include Condensing units, Direct expansion (DX) coil in air handlers, Remote evaporators with air-cooled chillers and Chiller with a remote air-cooled condensers. This Guide covers R-22, R-407C, R-410A, and R-134a used in commercial air conditioning systems.
Datacenter Liquid Cooling Methods
A variety of liquids could be considered for Data Center applications. When liquids are employed within separate cooling loops that do not communicate thermally, the system is considered to be air cooling. The most obvious illustration covers the chilled-water CRACs that are usually deployed at the periphery of many of today’s data centers. At the other end of the scale, the use of heat pipes or pumped loops inside a computer, wherein the liquid remains inside a closed loop within the server, also qualifies as air-cooled electronics, provided the heat is removed from the internal closed loop via airflow through the electronic equipment chassis.
Mantenere e pulire l'acciaio inossidabile
L'acciaio inossidabile garantisce la sua superiore resistenza alla corrosione sviluppando una pellicola superficiale di ossido di cromo durante il processo di fabbricazione. Per garantire la massima protezione dalla corrosione, l'acciaio inossidabile deve essere mantenuto pulito e avere un adeguato apporto di ossigeno per combinarsi con il cromo presente nell'acciaio inossidabile per formare “ossido di cromo”, uno strato protettivo di passivazione. L'acciaio inossidabile è il materiale di costruzione più conveniente disponibile per prolungare la durata di una torre di raffreddamento, un raffreddatore a circuito chiuso o un condensatore evaporativo nel settore HVAC-R.
Cooling Towers (Free Cooling Operation)
Cooling towers are used to dissipate heat from air conditioning or industrial process systems. Many of the air conditioning systems currently in use only operate during the summer cooling season, but there are numerous air conditioning and process systems that require cooling year-round. In some cases, the entire cooling system is required to operate during the winter. The cooling tower is required to provide the same 85° F (30° C) or colder water to the system as it does in the summer, but it does so at lower ambient temperatures. However, there are some applications designed to use the cooling tower for “free cooling”. Free cooling is when chilled water is cooled by cooling tower water through the use of heat exchangers without the use of refrigerant compressors. Free cooling can be accomplished when ambient conditions allow the cooling tower to produce “chilled water” for the system.
Cooling Towers (Capacity Control)
Free cooling systems can generate significant savings for the owners of such systems. However, the amount of potential energy savings available depends almost totally on the overall system design and on the selection of equipment for use in the system. In general, the designer must balance higher equipment cost with greater opportunity for energy savings. Fortunately, these savings — and their associated costs —are reasonably quantifiable so that designers can make intelligent choices guided by reliable information. This article will describe Capacity Control Methods in free cooling design schemes.
Constant Air Volume (CAV) Systems
HVAC air systems can be either centralized or decentralized. Centralized air systems receive their cooling and heating energy from a remote central plant. Decentralized HVAC air systems contain the central heating and cooling plant equipment within the air system itself. HVAC air systems can also be constant air volume (CAV) or variable air volume (VAV). CAV systems deliver constant supply airflow at a variable temperature. VAV systems deliver variable supply airflow at a constant temperature. CAV and VAV air systems can be further subdivided into systems that condition a single temperature zone and systems that condition multiple temperature zones.
Controlli e automazione
Raffreddamento a liquido diretto su chip: il futuro della gestione termica dei data center ad alta densità
Data center power densities have surged to 12-30 kW per rack, making liquid cooling essential. Learn how single-phase and two-phase direct-to-chip systems work, refrigerant selection criteria, and critical design considerations for hoses, tubing, and couplings in modern high-density data centers.
Diagrammi di controllo HVAC
In questo post del blog introdurremo alcuni dei diagrammi di controllo HVAC più comuni. Forniremo inoltre una breve spiegazione di ciascun diagramma e di come i suoi componenti interagiscono. Gli schemi di controllo HVAC sono strumenti essenziali per la progettazione, l'installazione e la manutenzione dei sistemi HVAC. Forniscono una rappresentazione visiva dei componenti del sistema, di come sono interconnessi e di come sono controllati. Queste informazioni possono essere utilizzate per risolvere problemi, ottimizzare le prestazioni e prendere decisioni informate sugli aggiornamenti del sistema.