Temperature control

About: Temperature control is a research topic. Over the lifetime, 39948 publications have been published within this topic receiving 207943 citations. The topic is also known as: temperature regulation & thermal control.

An application of electrothermal feedback for high resolution cryogenic particle detection

Abstract: A novel type of superconducting transition edge sensor is proposed. In this sensor, the temperature of a superconducting film is held constant by feeding back to its position on the resistive transition edge. Energy deposited in the film is measured by a reduction in the feedback Joule heating. This mode of operation should lead to substantial improvements in resolution, linearity, dynamic range, and count rate. Fundamental resolution limits are below ΔE=√kT2C, which is sometimes incorrectly referred to as the thermodynamic limit. This performance is better than any existing technology operating at the same temperature, count rate, and absorber heat capacity. Applications include high resolution x‐ray spectrometry, dark matter searches, and neutrino detection.

RF ablation system and method having automatic temperature control

Abstract: A plurality of electrodes are positioned at the distal end of a catheter such that the electrodes may be positioned proximal biological tissue. A select number of the electrodes have a temperature sensing device associated with them for providing a temperature signal indicative of the temperature at the interface between the electrode and the tissue. A generator operates under the control of a processor to apply power to each of the electrodes. The power has an associated phase angle and, within a time duration, a plurality of alternating on periods and off periods, one set of adjacent on and off periods defining a duty cycle. The processor is programmed to determine the temperature at the electrode/tissue interface based on the temperature signals, compare the temperature to a target temperature and to adjust the power to the electrode accordingly. Such adjustments may comprise an increase or decrease in the duty cycle, a setting of the duty cycle to zero followed by an incremental increase in the duty cycle or a power interrupt.

Automatic over-temperature control apparatus for a therapeutic heating device

Abstract: The use of radio frequency currents to heat and destroy neurological tissues is well known in the field of neurosurgery and typically involves monitoring of the tissue temperature as it is being heated by an in-dwelling electrode. This patent deals with an apparatus and method which enables the operator of such apparatus to be in control of the rise of temperature and the increase in radio frequency power delivered to such electrodes, and yet also to pre-set a temperature and have control circuitry and other means to prevent the electrode temperature to exceed a set temperature point. We refer to this as an over-temperature control for heat lesion generation equipment in the case of neurosurgery. The system is a hybrid between a purely manually controlled radio frequency heating unit and a completely automatically controlled radio frequency unit, the latter being such that it automatically raises the radio frequency power and feedbacks on a set temperature to stabilize the final electrode temperature. The present invention retains the important position of the human operator in establishing the rise of temperature and yet affords the advantage of temperature stabilization at a fixed end point and thereby gives the benefits of a fully automatic control system to the added asset of safety and human control.

Thermal Regulation of Building-Integrated Photovoltaics Using Phase Change Materials

Abstract: Elevated operating temperatures reduce the efficiency of photovoltaic devices. The use of a phase change material to moderate building integrated photovoltaic temperature rise has been investigated by experiments and numerical simulations. Experimental data are used to validate the previously developed two-dimensional finite volume heat transfer model conjugated hydrodynamically to solve the Navier–Stokes and energy equations. A parametric study of a design application is also reported. Temperatures, velocity fields and vortex formation within the system were predicted for a variety of configurations using the experimentally validated numerical model. Temperature distributions predicted fordifferent insolation and ambient temperatures at the photovoltaic surface show that the moderation of temperature achieved can lead to significant improvements in the operational efficiency of photovoltaic facades.

Design optimization of electric vehicle battery cooling plates for thermal performance

Abstract: The performance of high-energy battery cells utilized in electric vehicles (EVs) is greatly improved by adequate temperature control. An efficient thermal management system is also desirable to avoid diverting excessive power from the primary vehicle functions. In a battery cell stack, cooling can be provided by including cooling plates: thin metal fabrications which include one or more internal channels through which a coolant is pumped. Heat is conducted from the battery cells into the cooling plate, and transported away by the coolant. The operating characteristics of the cooling plate are determined in part by the geometry of the channel; its route, width, length, etc. In this study, a serpentine-channel cooling plate is modeled parametrically and its characteristics assessed using computational fluid dynamics (CFD). Objective functions of pressure drop, average temperature, and temperature uniformity are defined and numerical optimization is carried out by allowing the channel width and position to vary. The optimization results indicate that a single design can satisfy both pressure and average temperature objectives, but at the expense of temperature uniformity.