Differing terms and definitions[ edit ] Ground source heating and cooling This section needs expansion. You can help by adding to it. February Some confusion exists with regard to the terminology of heat pumps and the use of the term "geothermal". Though some confusion arises when the term "geothermal" is also used to apply to temperatures within the first metres of the surface, this is "Earth heat" all the same, though it is largely influenced by stored energy from the sun.
Different from a snow loading study, the assessment of ice and snow has no prescribed or regulated criterion, standard or procedure by building codes to assist designers or engineers. Furthermore, an ice and snow assessment focusses on events that would interrupt building operations, services, or create a perceived or real hazard to people or property, compared to snow loading studies that are focused mainly on structural integrity and the potential for failure at a prescribed criterion target.
The current state of the industry is largely due to the complexity of the issues and corresponding number of variables that need to be considered. Furthermore, the analysis and computational models that would be required to predict the potential for building designs to experience hazardous ice and snow formations is beyond the current capabilities of economic study.
Thus, the industry must rely on experience-based assessments conducted by consultants having a broad knowledge and experience in: Characteristics of an Ice and Snow Assessment The assessment of the potential for ice and snow hazard is generally accomplished through a design review process that considers historical meteorological statistics, local topography and surrounding buildings or structures in combination with the proposed building design.
This allows for the frequency, directionality, and severity of winter storm conditions on the site specific microclimate to be evaluated and expressed in terms of potentially problematic conditions.
If potentially problematic ice or snow formations are anticipated, design modifications can be recommended to reduce the frequency and severity of hazards.
If there is limited knowledge of the performance of a particular design feature, material or the affecting microclimate condition with the corresponding design feature or material, the refinement and validation of a mitigation concept can be recommended.
This process is typically accomplished by conducting a full-scale physical test in a controlled cold room environmental chamber.
This type of testing can be costly, however it is necessary to allow for the creation of the specific microclimate conditions required or in question to validate and refine a mitigation strategy or concept before it is implemented.
To demonstrate the varied aspects of ice and snow assessment, the following topics are discussed: Building Geometries within their Microclimate Once historical meteorological statistics have been reviewed and assessed in combination with the proposed building geometries, potentially negative influences of the building's performance within the local microclimate can be realized and improved upon.
Examples of negative geometry and microclimate interactions can include: If these potential issues are identified and evaluated early in design, the risks of ice and snow hazard can be managed and improved upon, reducing their impact on cost and schedule, and resulting in more appealing aestheticsas integrated mitigation designs can be investigated.
Envelope Design Considerations Similarly, the ice and snow assessment can contribute to the decision process regarding envelope design. It is becoming evident that strategies to reduce energy consumption in buildings have a direct impact on the performance of the exterior building skin.
Solar shading devices, high-performance wall assemblies and glazing products are generating significant energy savings in terms of long-term building heating and cooling requirements. An example of snow formation on curtain wall glazing. Roof The roof surface of a building can be a complex region, not only in terms of geometry or the presence of skylights, mechanical equipment, etc.
Snow load considerations for ice and snow formations on roof surfaces govern the structural design of the roof and can significantly influence the entire structural design down to the footings of a building.
However, as previously discussed, the prescribed snow load process is focused on long-term safety and durability of the structure to avoid catastrophic failure, and is therefore less focused on issues that can influence day to day building operations, public perception and the potential for falling, windblown or sliding snow hazards from a building.
Given these differences, there are two specific areas where the ice and snow assessment can contribute significantly to the structural design. These are sliding or moving snow on slippery sloped surfaces metal or membrane roofs ; and the integrity of the roof drainage path during the winter months.
The first topic has to do with ice and snow accumulations that in the correct meteorological conditions can slide or move, damaging roof projections, mechanical equipment, lighting protection, roof seams, parapet walls and in severe conditions the sliding ice and snow can slide completely from the roof surface damaging property or injuring people below.
Circumstances that can lead to a sliding ice and snow scenario can be complex and are not well documented within the industry. This is where an assessment from an experienced ice and snow consultant can prove invaluable, if utilized during initial design rather than in a retrofit condition, which is often the case.Motor analysis support tool, Electric Machine Design Toolkit, of ANSYS Maxwell, performs in full automatic an efficiency map computation and speed-torque characteristic of a PM motor and realizes significant efficiency in development time by the function of displaying an efficiency map graph.
The purpose of this RFI is to solicit feedback from industry, academia, research laboratories, government agencies, and other stakeholders to assist in further defining the scope and priorities of EERE’s commercialization and entrepreneurship activities.
Heat pipes are becoming increasingly popular as passive heat transfer technologies due to their high efficiency. This paper provides a comprehensive review of the state-of-the-art applications, materials and performance of current heat pipe devices.
structure analysis and design. The key observations are: 1) the building morphology has a significant effect on the annual energy consumption, 2) placement of the structural. This study demonstrates how to design pores in building materials so that incoming fresh air can be efficiently tempered with low-grade heat while conduction losses are kept to a minimum.
A glossary on new product development / integrated product development terms and acronyms.