Cooling Jacket Research Articles

A Cooling Jacket Design for a Starter–Generator Body

A Cooling Jacket Design for a Starter–Generator Body

Causes of Leaks in the Main Engine Cooling Jacket MT. Mulia Karsa 2

Between the cylinder wall and the cylinder block is the cylinder block is an intermediary cooling device called the primary cooling jacket of the main engine system. Here, the cooling fluid is able to draw heat away from the cylinder wall and continue its circulation. Due to an issue with the jacket cooling of the primary engine system, ship operations had to be suspended for maintenance, prompting the current investigation. The study aims to pinpoint the reasons behind jacket cooling leakage in the main engine room and suggest viable countermeasures. Observation, interviews, and reviews of relevant literature are just a few methods used to gather information. The study took a descriptive, qualitative approach, using tools like SHEL and the fishbone diagram to analyze data. According to the results of this research, a lack of attention to the planning and maintenance system for the main engine, o-ring deterioration in the jacket cooling main engine system, corrosion of the cooling jacket, rust formation in the tank, suboptimal water preheating temperature, and a lack of maintenance all contribute to leaks in the main engine cooling system. Several variables contribute to the main engine's less-than-ideal cooling efficiency. The jacket cooling system damage system's o-ring or a leak in the jacket cooling system are two examples of these problems with the primary engine system. In addition, the primary engine cooler's cooling water jacket is subpar, and its circulation is subpar. In addition, the exhaust gas temperature from the main engine is inconsistent, and rising temperatures have not yet resulted in the engine's shutoff. The primary engine system performs maintenance at the specified intervals specified in the handbook to handle problems with jacket cooling leaks. O-ring and cooling jacket replacement, chemical dosing, water pH testing, and routine temperature checks are all part of the maintenance process.

Ultrasonic Experimental Evaluation of the Numerical Model of the Internal Fluid Flow in the Kidney Cooling Jacket

Ultrasonic Experimental Evaluation of the Numerical Model of the Internal Fluid Flow in the Kidney Cooling Jacket

Thermal Behaviour of the Cooling Jacket Belonging to a Liquid Oxygen/Liquid Methane Rocket Engine Demonstrator in the Operation Box

The cooling jackets of liquid rocket engines are composed of narrow passages surrounding the thrust chambers and ensure the reliable operation of the engine. Critical conditions may also be encountered, since the cooling jackets of cryogenic engines, such as those using LOX/LCH4 propellants, are based on a regenerative strategy, where the fuel is used as a refrigerant. Consequently, deterioration modes near where pseudocritical conditions are reached or low heat transfer coefficients where the fuel becomes a vapour and must therefore be managed. The verification of the cooling jacket behaviour to consolidate the design solutions in all the extreme points of the operating box represents a very important phase. The present paper discusses the full characterization of the HYPROB (HYdrocarbon PROpulsion test Bench Program) first unit of the final demonstrator, (DEMO-0A), by considering the working points within the limits of the operating box and comparisons with the nominal conditions are given. In this way, a full understanding of the cooling system behaviour, affecting the working of the entire thrust chamber, is accomplished. Moreover, the design strategy and choices have been confirmed, since the verifications also include potentially even more extreme conditions with respect to the nominal ones. The investigation has been numerically performed and supported the thermo-structural analyses accomplished before the final firing campaign, completed in December 2022. Since little information is available in the literature on LOX/LCH4 engines, suggestions are given as to the organization of the numerical simulations, which support the design of such rocket engine cooling systems.

Sheetal Kavach: Hybrid Cooling Jacket for Healthcare Workers in India

Sheetal Kavach: Hybrid Cooling Jacket for Healthcare Workers in India

Simulation of Thermal Decomposition of Calcium Oxide in a Backward Step Tubular Reactor Containing a Cooling Jacket to Enhance the Heat Transfer and the Rotation Rate

The chemical reactions widely operate in industries to enhance the heat transfer rate among the chosen domain. In the current article, we are going to observe an exothermic reaction of calcium oxide and water in a backward step tubular reactor with a cooled surrounded surface. The tubular reactor will be considered axisymmetric with an aspect ratio of 0.5, 0.6, and 0.7 from half radius to the length of the reactor. The governing partial differential equations of mass, momentum, and energy and diffusion equations are solved using the commercial package of finite element method of COMSOL Multiphysics 5.6. A parametric study is done by using the Reynolds number in the range and activation energy E in a range from 71,000 J/mol to 75,000 J/mol. The initial concentration of calcium oxide is tested from 1% to 3%. The computational results will be displayed for the upstream and downstream of the channel. It was concluded that the temperature difference is increasing linearly against the concentration of calcium hydroxide upstream and nonfunctional downstream. The average Sherwood and Nusselt numbers give a positive response with increasing the aspect ratio as well as the Reynolds number. The rotation rate at the middle of the downstream was also concluded using the Reynolds number and aspect ratio.

Cooling Between Exercise Bouts and Post-exercise With the Fan Cooling Jacket on Thermal Strain in Hot-Humid Environments.

This study investigated the effects of cooling between exercise bouts and post-exercise with a commercially available fan cooling jacket on thermal and perceptual responses during and following exercise in hot-humid environments. Ten male athletes completed two 30 min cycling bouts at a constant workload (1.4 watts⋅kg–1 of body mass) with a 5 min recovery period in between. Exercise was followed by a 10 min recovery period. In an environmental chamber (33°C, 65% relative humidity), participants performed two trials with (FCJ) or without (CON) the fan cooling jacket on a T-shirt during the 5 min inter-exercise and 10 min post-exercise recovery periods. Mean, chest and upper arm skin temperatures, and thermal sensation and comfort were lower in FCJ than CON trial during and following exercise (P < 0.05). Thigh and calf skin temperatures, infrared tympanic temperature and heart rate were lower in FCJ than CON trial during the experimental trials (P < 0.05). The rates of fall in mean, chest and upper arm skin temperatures, infrared tympanic temperature and thermal sensation and comfort were faster in FCJ than CON trial during both recovery periods (P < 0.05). There were faster rates of fall in thigh and calf skin temperatures and heart rate in FCJ than CON trial during the post-exercise recovery period (P < 0.05). No difference was observed between trials in the rating of perceived exertion (P > 0.05). This study indicates that cooling between exercise bouts and post-exercise with the fan cooling jacket would effectively mitigate thermal strain and perception/discomfort during and following exercise in hot-humid environments. This garment would reduce whole-body skin temperature quickly while promoting falls in lower-body as well as upper-body skin temperatures.

Comparative Study of Three Stator Cooling Jackets for Electric Machine of Mild Hybrid Vehicle

Three stator cooling jacket concepts, including a new cooling jacket concept with parallel straight spiral channels, are evaluated for electric machine of mild hybrid electric car. Steady-state cooling jacket thermal flow analysis and transient-state full motor simulations with circumferential, axial, and spiral jacket concepts are carried out to predict their heat transfer performance and temperature distribution. A prototype motor has been made with the new jacket concept. Infrared thermography is performed to detect the transient temperature distribution of the motor stator windings and laminations for validation of the thermal flow analysis.

Hand and torso pre-cooling does not enhance subsequent high-intensity cycling or cognitive performance in heat

ABSTRACT The purpose of this study was to compare the separate and combined effects of two practical cooling methods (hand and torso) used prior to exercise on subsequent high-intensity cycling performance in heat. Ten trained male cyclists (V̇O2peak: 65.7 ± 10.7 ml.kg−1.min−1) performed four experimental trials (randomised within-subjects design) involving 30-min of pre-cooling (20-min seated; PRE-COOL, 10 min warm-up; PRE-COOL+WUP), while using a: (1) hand-cooling glove (CG); (2) cooling jacket (CJ); (3) both CG and CJ (CG+J); or (4) no-cooling (NC) control, followed by a cycling race simulation protocol (all performed in 35.0 ± 0.6°C and 56.6 ± 4.5% RH). During the 30-min of pre-cooling, no reductions in core (Tc) or mean skin temperature (Tsk) occurred; however, Tsk remained lower in the CJ and CG+J trials compared to NC and CG (p = 0.002–0.040, d= 0.55–1.01). Thermal sensation ratings also indicated that participants felt “hotter” during NC compared to all other trials during both PRE-COOL and PRE-COOL+WUP (p = 0.001–0.015, d= 1.0–2.19), plus the early stages of exercise (sets 1–2; p = 0.005–0.050, d= 0.56–1.22). Following cooling, no differences were found for absolute Tc and Tsk responses between trials over the entire exercise protocol (p > 0.05). Exercise and cognitive (working memory) performance also did not differ between trials (p = 0.843); however, cognitive performance improved over time in all trials (p < 0.001). In summary, pre-cooling (20-min seated and 10-min warm-up) in heat did not improve subsequent high-intensity cycling performance, cognitive responses and associated thermoregulatory strain (Tc and Tsk) compared to control.

Design of Smart Cooling Jacket for 2-Wheeler Riders

Design of Smart Cooling Jacket for 2-Wheeler Riders

Effectiveness of hand cooling and a cooling jacket on post-exercise cooling rates in hyperthermic athletes

This study compared the effects of a hand cooling glove (∼16°C water temperature; subatmospheric pressure of −40 mmHg) and a cooling jacket (CJ) on post-exercise cooling rates (gastrointestinal core temperature, Tc; skin temperature, Tsk) and cognitive performance (the Stroop Colour–Word test). Twelve male athletes performed four trials (within subjects, counterbalanced design) involving cycling at a workload equivalent to 75% ⩒O2max in heat (35.7 ± 0.2°C, 49.2 ± 2.6% RH) until a Tc of 39°C or exhaustion occurred. A 30-min cooling period (in 22.3 ± 0.3°C, 42.1 ± 3.6% RH) followed, where participants adopted either one-hand cooling (1H), two-hand cooling (2H), wore a CJ or no cooling (NC). No significant differences were seen in Tc and Tsk cooling rates between trials; however, moderate effect sizes (d = 0.50–0.76) suggested Tc cooling rates to be faster for 1H, 2H and CJ compared to NC after 5 min; 1H and CJ compared to NC after 10 min and for CJ to be faster than 2H at 25–30 min. Reaction times on the cognitive test were similar between all trials after the 30 min cooling/no-cooling period (p > .05). In conclusion, Tc cooling rates were faster with 1H and CJ during the first 10 min compared to NC, with minimal benefit associated with 2H cooling. Reaction time responses were not impacted by the use of the glove(s) or CJ.

Three-D Numerical Thermal Analysis of Electric Motor with Cooling Jacket

The need of a sustainable clean future has paved the way for environmental friendly electric vehicle technology. In electric vehicles, overloading is limited by the maximum temperature rise in the electric motor. Although an improved cooling jacket design is of vital importance in lowering the maximum temperature of the motor, there has not been as much study in the thermal analysis of motors compared to electromagnetic design studies. In this study, a three-dimensional steady state numerical method is used to investigate the performance of a cooling jacket using water as the primary coolant of a three-phase induction motor with special emphasis on the maximum temperature and the required pumping power. The effective thermal conductivity approach is employed to model the stator winding, stator yoke, rotor winding and rotor yoke. Heat transfer by induced air is treated as forced convection at the motor ends and effective conductivity is obtained for air in the stator-rotor gap. Motor power losses, i.e., copper and iron losses, are treated as heat generation sources. The effect of bearings and end windings is not considered in the current model. Pressure and temperature distributions under various coolant flow rates, number of flow passes and different cooling jacket configurations are obtained. The study is successful in identifying the hot spots and understanding the critical parameters that affect the temperature profile. The cooling jacket configuration affects the region of maximum temperature inside the motor. Increasing the number of flow passes and coolant flow rate decreases maximum motor temperature but results in an increase in the pumping power. Of the cooling jacket configurations and operating conditions investigated, a cooling jacket with six passes at a flow rate of 10 LPM with two-port configuration was found to be optimal for a 90-kW induction motor for safe operation at the maximum output.

Thermal Analysis of IPMSM with Water Cooling Jacket for Railway Vehicles

In this paper, the water cooling method among the forced coolant cooling methods is considered to be applied to the 110kW-class IPMSM for railway vehicles. First, basic thermal property analysis of the IPMSM is conducted using the three-dimensional thermal equivalent network method. Then, based on the results of the basic thermal property analysis, some design requirements for the water cooling jacket are deduced and a basic design of the water cooling jacket is carried out. Finally, thermal equivalent circuit of the water cooling jacket is attached to the IPMSM’s 3D thermal equivalent network and then, the basic thermal and effectiveness analysis are conducted for the case of applying the water cooling jacket to the IPMSM. In the future, the thermal variation trends inside the IPMSM by the application of the water cooling jacket is expected to be quickly and easily predicted even at the design step of the railway traction motor.

Postexercise Cooling Rates in 2 Cooling Jackets

Cooling jackets are a common method for removing stored heat accumulated during exercise. To date, the efficiency and practicality of different types of cooling jackets have received minimal investigation. To examine whether a cooling jacket containing a phase-change material (PC17) results in more rapid postexercise cooling than a gel cooling jacket and a no-jacket (control) condition. Randomized, counterbalanced design with 3 experimental conditions. Participants exercised at 75% V o(2)max workload in a hot climate chamber (temperature = 35.0 +/- 1.4 degrees C, relative humidity = 52 +/- 4%) for 30 minutes, followed by postexercise cooling for 30 minutes in cool laboratory conditions (ambient temperature = 24.9 +/- 1.8 degrees C, relative humidity = 39% +/- 10%). Twelve physically active men (age = 21.3 +/- 1.1 years, height = 182.7 +/- 7.1 cm, body mass = 76.2 +/- 9.5 kg, sum of 6 skinfolds = 50.5 +/- 6.9 mm, body surface area = 1.98 +/- 0.14 m(2), V o(2)max = 49.0 +/- 7.0 mLxkg(-1)xmin(-1)) participated. Three experimental conditions, consisting of a PC17 jacket, a gel jacket, and no jacket. Core temperature (T(C)), mean skin temperature (T(Sk)), and T(C) cooling rate ( degrees C/min). Mean peak T(C) postexercise was 38.49 +/- 0.42 degrees C, 38.57 +/- 0.41 degrees C, and 38.55 +/- 0.40 degrees C for the PC17 jacket, gel jacket, and control conditions, respectively. No differences were observed in peak T(C) cooling rates among the PC17 jacket (0.038 +/- 0.007 degrees C/min), gel jacket (0.040 +/- 0.009 degrees C/min), and control (0.034 +/- 0.010 degrees C/min, P > .05) conditions. Between trials, no differences were calculated for mean T(Sk) cooling. Similar cooling rates for all 3 conditions indicate that there is no benefit associated with wearing the PC17 or gel jacket.

SELF-TUNING NEURO-FUZZY GENERALIZED MINIMUM VARIANCE CONTROLLER

The development of a Self-Tuning Neuro-Fuzzy Generalized Minimum Variance (GMV) controller is described. It uses fuzzy expert knowledge of the dynamic weightings to meet desired closed-loop stability and performance requirements. The controller is formulated in a polynomial system approach mixed with a Neuro-Fuzzy model and Fuzzy Self-Tuning mechanism. The proposed method is applied to a model of the Continuous Stirred Tank Reactor with Cooling Jacket and is compared with a PI controller, GMV controller with the correct model and a Fuzzy-PI controller. Simulation results are presented to demonstrate the performance of the proposed method.

Development of Cooling Jacket

Development of Cooling Jacket

Wearing a Cooling Jacket During Exercise Reduces Thermal Strain and Improves Endurance Exercise Performance in a Warm Environment

The aim of the present study was to investigate the effect of wearing a cooling jacket on thermoregulatory responses and endurance exercise performance in a warm environment. Nine untrained male subjects cycled for 60 minutes at 60% Vo(2)max (Ex1) and then immediately exercised to exhaustion at 80% Vo(2)max (Ex2) in 32.0 +/- 0.2 degrees C and 70-80% relative humidity. Four separate conditions were set during exercise: no water intake (NW), water intake (W), wearing a cooling jacket (C) and the combination of C and W (C+W). Rectal temperatures (T(re)) before Ex1 were not different between the 4 conditions, whereas at the end of Ex1 T(re) of C+W was significantly lower than the C and W (p < 0.05). Mean skin temperature (T(sk)) was significantly lower in C and C+W than the NW and W during Ex1. Heart rate of C and C+W were significantly lower than the NW and W, and rating of perceived exertion (RPE) in C+W was lower than in the other conditions. Exercise time to exhaustion was significantly longer in C+W than in the other conditions (NW < W, C < C+W; p < 0.05), whereas T(re) at exhaustion was not different. Our results indicate that the combination of wearing a cooling jacket and water intake enhances exercise endurance performance in a warm environment because of a widened temperature margin before the critical limiting temperature is reached and also because of decreased thermoregulatory and cardiovascular strain.

Neuro-Fuzzy Generalized Minimum Variance Control of Nonlinear Systems

A Generalized Minimum Variance controller is used together with a Neuro-Fuzzy identification algorithm to produce a Neuro-Fuzzy Generalized Minimum Variance controller based on a polynomial systems approach. The advantage of this approach is that it does not require an explicit model of the plant. The controller is applied to a model of the Continuous Stirred Tank Reactor with Cooling Jacket. The Neuro-Fuzzy Generalized Minimum Variance control is compared with the Generalized Minimum Variance with correct model and a digital filter used as a controller with tracking reference, perturbance rejection and robustness tests.

Efficacy of Aluminum Cooling Jacket During Continuous Exercise

Efficacy of Aluminum Cooling Jacket During Continuous Exercise

Efficacy of Aluminum Cooling Jacket During Continuous Exercise

2132 The ability to sustain a lower core body temperature (T c) during continuous, moderately intense activity can lead to improvements in work performance and reduce the risk of a heat related medical emergencies. PURPOSE: The purpose of this investigation was to determine the efficacy of an aluminum weave jacket during a 20-minute continuous jog. METHODS: Eight 19–45 year old, healthy, and active males were recruited to perform two 20-minute trials. The trials required the participants to run at 60% of their VO2max around a 20 by 20-meter square. Cadence for the trials was set according to the values calculated using a Multistage Fitness Test during the VO2max. Two conditions were tested: 1) wearing an aluminum weave jacket (WCJ); 2) not wearing an aluminum cooling jacket (NCJ). Pre- and Post- Core temperature (T c), and post- ratings of perceived exertion (RPE), pre- and post- heart rate (HR), and post- thermal sensation (TS) were assessed at the beginning and end of each trial. RESULTS: The results showed that there was a significant increase in T c (1.33 °C) from pre- to post- exercise among groups. However, there was no significant difference in T c, RPE, TS, and HR between trials. CONCLUSIONS: The use of an aluminum weave jacket does not appear to aid in reducing thermal load during a 20-minute continuous jog. Project supported by Xton, Inc.