Verification of Thermal Comfort of Combined Convection-Radiation Air Conditioning System using Building Structure

Combined Convection-Radiation Air Conditioning System using Building Structure combines the advantages of TABS and convection air conditioning. In ordinary TABS, pipes are buried in the frame, but here pipes are laid on the lower (ceiling) surface of the floor slab. Also, jets from a Convection-enhancing Spot fan are sprayed toward the ceiling surface, promoting convection on the frame surface. This airflow promotes timely heat dissipation stored in the frame, and a micro-airflow environment can be formed in the living area. This paper aimed to verify thermal comfort and proper operation. Subjects were given simulated work of low to high metabolic rate, and were asked to report the thermal sensation and comfort in a micro-airflow environment. It was confirmed that comfort could be maintained even at a temperature higher than the general air-conditioning temperature, and an appropriate operating method according to the metabolic rate was elucidated.publishedVersio

Verification of Thermal Comfort of Combined Convection-Radiation Air Conditioning System using Building Structure

Combined Convection-Radiation Air Conditioning System using Building Structure combines the advantages of TABS and convection air conditioning. In ordinary TABS, pipes are buried in the frame, but here pipes are laid on the lower (ceiling) surface of the floor slab. Also, jets from a Convection-enhancing Spot fan are sprayed toward the ceiling surface, promoting convection on the frame surface. This airflow promotes timely heat dissipation stored in the frame, and a micro-airflow environment can be formed in the living area. This paper aimed to verify thermal comfort and proper operation. Subjects were given simulated work of low to high metabolic rate, and were asked to report the thermal sensation and comfort in a micro-airflow environment. It was confirmed that comfort could be maintained even at a temperature higher than the general air-conditioning temperature, and an appropriate operating method according to the metabolic rate was elucidated

Magnetic Field Measurement of 2-m-Long Model of Beam Separation Dipole for the HL-LHC Upgrade

Abstract: KEK has been developing a beam separation dipole magnet for the high luminosity large hadron collider upgrade. The magnet has a coil aperture of 150 mm and uses NbTi superconducting cable. A dipole magnetic field of 5.6 T is generated at 12 kA at 1.9 K to provide a field integral of 35 T·m. KEK has started the development of the first 2-m-long model magnet to evaluate the design and performance of the beam separation dipole magnet. The excitation test at 1.9 K of the first 2-m-long model magnet was performed from April to June 2016 at KEK. This paper presents the results of the magnetic field measurements of the first 2-m-long model magnet by a rotating coil probe

Fabrication and Test Results of the First 2 m Model Magnet of Beam Separation Dipole for the HL-LHC Upgrade

The large aperture superconducting beam separation dipole (D1) must be developed as part of the high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN. The most important specifications of the D1 are a coil aperture of 150 mm and field integral of 35 T·m at 12.0 kA and 1.9 K. The technical challenges of this magnet include predicting the changes in the size of the coils during fabrication, achieving a high radiation resistance, and management of the iron saturation. KEK is in charge of developing the D1. After conducting a series of design studies, a design consisting of a single-layer coil based on Nb-Ti technology with a collared yoke structure was selected. The fabrication of the first 2 m model of the D1 started at KEK in 2015. Newly developed radiation resistant glass-fiber-reinforced-plastics were utilized as coil parts in the accelerator magnets for the first time. The 2 m model was subjected to two cycles of cold test in the vertical cryostat at KEK. In this paper, we report on the fabrication of the 2 m model. We also present and discuss the quench test results from the perspective of the coil prestress

Field Measurement to Evaluate Iron Saturation and Coil End Effects in a Modified Model Magnet of Beam Separation Dipole for the HL-LHC Upgrade

A beam separation dipole magnet for the high luminosity large hadron collider upgrade is developed. The development of the 2-m-long model magnet (MBXFS1) was initiated so as to evaluate the design and performance of the beam separation dipole magnet. In the first cold test in 2016, the quench performance was not satisfactory because the coil prestress at the pole was completely released during excitation. After reassembly to improve the quench performance, the excitation test of the modified model magnet (MBXFS1b) was performed at 1.9 K in 2017 at KEK. Due to the large coil aperture and limited outer diameter of the iron yoke, the control of iron saturation effects on the field quality has been a design issue. Regarding the magnetic performance, field saturation effects on the transfer function and the multipole field variation along the excitation, and coil end effects to the straight section need to be evaluated by the field measurement. In this paper, field measurement results will be presented and the comparison with the three-dimensional field calculation will be discussed