Handbook Of Low Temperature District Heating (G... TOP
This book reviews the history and evolution of district heating networks, with a focus on current and future issues of the district heating sector. Novel developments in the field of low temperature district heating are studied, limitations for safe operation and avoidance of bacteria are considered, and the associated improved performance of the system with fewer network losses is presented.
Handbook of Low Temperature District Heating (G...
This book showcases how the evolution of district heating networks is linked to the increased use of renewables and de-carbonized heat sources with specific focus to waste heat streams and solar energy systems. Considering the novelty of these technologies, technological developments and funding schemes for these investments are still immature to some extent. For that reason, a comprehensive review of the main aspects of energy planning as well as district heating economics and financing schemes for large-scale investments in renewable energy systems for district energy systems is performed.
This book is of interest to engineers, academics and officials interested in energy systems, presenting readers with the key concepts and tools to adapt to the evolution of district heating into an integrated, digitized and higher performing system.
Although HVAC is executed in individual buildings or other enclosed spaces (like NORAD's underground headquarters), the equipment involved is in some cases an extension of a larger district heating (DH) or district cooling (DC) network, or a combined DHC network. In such cases, the operating and maintenance aspects are simplified and metering becomes necessary to bill for the energy that is consumed, and in some cases energy that is returned to the larger system. For example, at a given time one building may be utilizing chilled water for air conditioning and the warm water it returns may be used in another building for heating, or for the overall heating-portion of the DHC network (likely with energy added to boost the temperature).
Energy efficiency can be improved even more in central heating systems by introducing zoned heating. This allows a more granular application of heat, similar to non-central heating systems. Zones are controlled by multiple thermostats. In water heating systems the thermostats control zone valves, and in forced air systems they control zone dampers inside the vents which selectively block the flow of air. In this case, the control system is very critical to maintaining a proper temperature.
Asian architectural temperature-control have different priorities than European methods. For example, Asian heating traditionally focuses on maintaining temperatures of objects such as the floor or furnishings such as Kotatsu tables and directly warming people, as opposed to the Western focus, in modern periods, on designing air systems.
The infant with environmental hyperthermia should be cooled to a normal axillary temperature by decreasing environmental heating or reducing thermal insulation (blankets or clothing). A bath or cooling mattress should not be necessary to correct hyperthermia caused by environmental overheating.
An infant with hypothermia can be rewarmed by a radiant heat or an incubator with higher air temperature. The simplest way to avoid overheating during rewarming with a radiant warmer is to use the skin temperature servocontrol with a set point of 36.5C. The rate of rewarming is probably not critical.
Careful attention to providing the best possible thermal environment increases the chance of survival and the quality of outcome, particularly in the small premature infant.Servocontrol is an electronic feedback system which functions as a thermostat to maintain a constant temperature at the site of a thermistor probe (usually on the skin over the abdomen) by regulating the heat output of an incubator or radiant warmer. Maintaining a constant abdominal skin temperature between 36.0 and 36.5ÁC is the simplest way to provide a "thermoneutral" environment, minimizing the number of calories needed to maintain normal body temperature and reducing the risks of cold stress or overheating.Although either skin or air temperature control can be used safely for most infants, skin temperature servocontrol is probably better for very young, small (below 1500 g) infants because the desired control temperature is more easily determined. Servocontrol is the only acceptable method of heat regulation for the infant cared for under a radiant warmer. 041b061a72