World Solar Challenge Research Articles

Virtual Development of a Challenger type, single-seater vehicle for the World Solar Challenge Competition

Abstract The paper presents the evaluation of the feasibility of a single-seat solar prototype vehicle for the World Solar Challenge competition, by estimating its autonomy. The research carried out contains several stages of study, including the development of mathematical models that are intended to be accurate enough to provide realistic predictions on the functional behaviour of the battery pack, so that it can be determined whether the designed vehicle will be able to complete the stages of the proposed competition. The paper also presents the CFD modeling approach, and the results obtained after simulating different body shapes advancements. In addition, the functional modeling approach is presented to evaluate the vehicle battery range, including the possibility to use different designs and types for the battery pack and to verify if the designed vehicle can achieve the race finish line.

Crashworthiness investigation on a Carbon Fiber Reinforced Plastic solar vehicle

This article presents a research study involving different simulations of crash tests by means of the finite element explicit dynamic software Ansys LS-Dyna to determine the roadworthiness of a fully composite chassis lightweight solar vehicle and its conformity to the World Solar Challenge (WSC) regulations. Furthermore, the paper describes the results of crash test simulations in conditions comparable with those of the standard homologation test, with an initial velocity of 15.5 m/s against a rigid barrier considering overlaps of 50% and 100%. The velocity measured at the base of the seat was later used in a sled test with a dummy to calculate the Head Injury Criterion (HIC), a number proportional to the probability of head injury caused by the impact. The values remained within the threshold of acceptability with overlap at 50% but exceeded the limit with the 100% overlap. With no load limiter implemented in the model, the seatbelt caused contact forces with the chest up to 14 kN against 6 kN of the typical load limiter used in road cars to limit damage to ribs and internal organs. Finally, the possibility of improving the front crash box was investigated by changing the crash box’s planar sandwich structure with corrugated ones and layup without foam between the carbon layers. Various values of semi-amplitudes (A) of the sinusoidal profile have been tested. With a value of A of 6 mm, the capacity to absorb energy from an impact at 9 m/s was close to the original configuration.

Design and Analysis of Solar Car Chassis for WSC 2023

The World Solar Challenger is a biennial global competition that plays a crucial role in testing and advancing the technological limits of solar-powered vehicles, particularly in the context of diverse travel conditions. The competition features three categories: Challenger Class, Cruiser Class, and Adventure Class. In 2023, Siam Technology University participated with the STC-4 model in the Cruiser Class. This research contributed to the vehicle's design, structural integrity, safety, and performance evaluation, essential for passing the scrutineering tests. Researchers were involved in shaping the vehicle's aerodynamics, analyzing structural aspects, and designing safety features compliant with World Solar Challenge 2023 requirements. The goal was to ensure the vehicle's safe participation and successful operation under varied conditions. The designed solar-powered vehicle, STC-4, aimed to address shortcomings from previous competitions. The structural framework, utilizing AISI 4130 steel, met safety standards, with a final weight of 258 kg. Structural testing ensured that the displacement did not exceed 25 mm. Finite Element Analysis confirmed the structural integrity, aligning with the team's objectives. In conclusion, this research significantly contributed to the design and safety aspects of solar-powered vehicles, as demonstrated by the successful participation of STC-4 in the World Solar Challenge 2023 Cruiser Class. The findings highlight advancements in structural design, safety measures, and performance capabilities, emphasizing the importance of continuous innovation in solar vehicle technology.

Applied engineering education for soft skills in the context of sustainability and mobility

Purpose The purpose of this paper is to address the need to rethink the traditional approach to education in the university engineering curriculum. The paper examines two engineering projects led by university students in Sweden: the design and construction of a solar-powered car taking part in the Bridgestone World Solar Challenge and the creation of a business model for the ownership phase of an electric car together with Polestar. Design/methodology/approach An extensive literature review was conducted. Students were interviewed and surveyed on their impressions of their learning experience in the two projects and student logbooks reviewed. Problem-based learning (PBL), the Conceiving, Designing, Implementing and Operating approach and the ABCD procedure are used. Results are compared to theories from the literature. Findings PBL in real-world settings can increase engineering students’ technical knowledge and improve their technical skills as they solve complex problems or propose solutions to such problems. Such projects also strengthen students’ commitment, self-confidence and self-esteem as well as promote co-operation and creativity. These are soft skills largely absent from traditional engineering education. Practical implications Innovative, student-led learning in the applied engineering curriculum can foster students’ soft skills in ways that teacher-led, lecture-style learning does not. Originality/value This research offers a timely perspective on an issue of current interest in engineering education: student-led learning versus teacher-led learning. The paper also provides two illustrative student-led projects that focus on sustainability and mobility.

Aerodynamic Effect of Wing Mirror Usage on the Solaris 7 Solar Car and Demobil 09 Electric Vehicle

This study focuses on the aerodynamic performances of two vehicles by Dokuz Eylul University Solaris Solar Car Project Team. The first vehicle (S7) is a solar-powered vehicle that is designed for World Solar Challenge and the second (D9) is an electric vehicle which is designed for Tubitak EV Challenge. Both vehicles are manufactured using polymer composites and challenged in mentioned races. In this research, a formal optimisation technique based on computational fluid dynamics (CFD) is used to determine the efficient aerodynamic structures under various scenarios. Results clearly show that strategists of the racing teams should take intoaccount the aerodynamic structure of the racing car. Especially before the races which based on efficiency, the apex line is determined, and mirrors should be replaced by back view camera.

Modelling and Dynamic Simulation of a Solar Vehicle for Track Events

World Solar Challenge (WSC) is a race held for solar powered vehicles from all around the world in every two years and multiple contestants from Turkey attend to this competition. The aim of this paper is to find a way of increasing the performance of vehicle during the qualifying lap of the race via modelling and dynamically simulating the solar vehicle. For this study, IPG/Carmaker software is used and a solar vehicle formed by two front and 1 rear wheel is modelled. Performance enhancer parameters including the vehicle design is selected and implemented to the model. Additional to vehicle model, race track is also modelled according to its physical features. According to gathered simulation results vehicle velocity and race duration is optimized. Vehicle is also tested on additional test cycles from literature and test outcomes are compared. Moreover, discussion between studies from literature is held.

Influence of the Diffuser on the Drag Coefficient of a Solar Car

Abstract The purpose of the research was to design a solar vehicle for Bridgestone World Solar Challenge competition which takes place biannually in Australia. The article, however, presents the aerodynamic research on the car body, especially on the exit diffuser. Numerous CFD simulations of different diffuser shapes were performed in ANSYS CFX software. The paper presents the results of pressure distribution on the body and velocity contours. The drag force acting on the car body is dependent on the pressure distribution. The article includes comparison of corresponding drag coefficient values for different cases. Furthermore, the variation of the lift force depending on the shape of the bodywork was also taken into consideration. The research shows that slight differences in the construction of the exit diffuser correspond to noticeable changes in the drag coefficient values (0.138 minimum, 0.168 maximum) and significant changes in the lift force (minimum 71 N, maximum 160 N).

Axalta Celebrates Success of Student Solar Car Teams at World Solar Challenge

Axalta Celebrates Success of Student Solar Car Teams at World Solar Challenge

Heuristic Optimization for the Energy Management and Race Strategy of a Solar Car

Solar cars are known for their energy efficiency, and different races are designed to measure their performance under certain conditions. For these races, in addition to an efficient vehicle, a competition strategy is required to define the optimal speed, with the objective of finishing the race in the shortest possible time using the energy available. Two heuristic optimization methods are implemented to solve this problem, a convergence and performance comparison of both methods is presented. A computational model of the race is developed, including energy input, consumption and storage systems. Based on this model, the different optimization methods are tested on the optimization of the World Solar Challenge 2015 race strategy under two different environmental conditions. A suitable method for solar car racing strategy is developed with the vehicle specifications taken as an independent input to permit the simulation of different solar or electric vehicles.

Ranges of applicability of a solar-battery car with single and double solar-trailers

In some parts of the globe, solar energy is available throughout the year. In areas where the terrain is mostly flat, it is justifiable to use solar power in the automotive industry. Previous publication explored the concept of a solar-battery car with single and double solar array-trailers. Solar array-trailers maximize the acquired solar energy thereby minimizing the use of battery power. The resulting excess power derived from solar-trailers can be used to drive the car and accessories that are necessary in some parts of the world. Building on previously published results, this paper aims to determine the applicable limits of the car-trailer concept. Variations to the reference configuration are considered, and the corresponding battery power needed is calculated. Upper limits to the drag area coefficient, ground inclination, and rolling resistance are established. Furthermore, an effective rolling resistance factor for the trailer is determined since manufacturing imperfections, component flexibilities and the misalignments of trailers limit the applicability of the car-trailer system. The use of trailers is not justifiable for an effective rolling resistance factor less than one.An ideal environment for the application of solar-battery cars, on a global scale, may be the drive across the Australian continent along the Stuart Highway/Highway1. Such a drive is used by the World Solar Challenge to assess the performance of various categories of solar cars. A similar track is used in this publication to assess the response of solar-battery cars with solar-trailers. Cumulative as well as daily energies required for such a drive are reported for a car, and a car with trailers. Furthermore, the response under clear/cloudy conditions, throughout the year, is discussed. The results are compared with energies required by a typical ‘race’ car. The paper concludes with a summary of the results.

A Function to Data Matrix (FDM) Approach for Mission Variables Consideration

Precise control of technical system variables in industrial processes and manned and unmanned missions is critical as their results should be achieved plenty. This takes place in Control Rooms (CR) where Operators make decisions based on the large amount of received data. This work proposes a method for weighting variables of a technical system based on their impact on the mission objectives. The relationships between variables and mission functions are defined using a Function to Data Matrix (FDM) in order to allow Operators to determine their criticality. The proposed method was applied for the mission control of the Racing Solar Vehicle Primavera1 which participated in the World Solar Challenge (WSC) 2013 in Australia.

Longitudinal dynamics simulation of a solar electric vehicle for driving strategy optimisation

In this paper, a generic model of a solar electric vehicle is presented along with a long-distance race simulation. Electrical system including a solar array, a battery, and an electrical motor and the longitudinal dynamics of the vehicle are modelled. The model is validated through test data. The race simulation is developed considering the specifications of the world solar challenge (WSC), a 3000 km-long solar car race held in Australia. This simulation provides an environment to test the design of the vehicle and determine an optimal race strategy maximising the performance. Furthermore, a sensitivity analysis of race performance to vehicle mass and aerodynamic drag is carried out. Additionally, the impact of weather conditions on race performance is analysed.

Design and development of the Sunswift eVe solar vehicle: a record-breaking electric car

The Sunswift project of the University of New South Wales, Australia, exists to provide university students with a multi-disciplinary engineering challenge, enhancing the true educational value of their degree with a unique hands-on real-world experience of creating solar–electric hybrid vehicles. The design and development of the low-drag ‘solar supercar’ Sunswift eVe car are described here, detailing the student-led process from initial concept sketches to the completed performance vehicle. eVe was designed to demonstrate the potential of effective solar integration into a practical passenger-carrying vehicle. It is a two-seater vehicle with an on-body solar array area of 4 m2 and a battery capacity of 16 kW h, which is capable of sustained speeds over 130 km/h and a single-charge range of over 800 km. Carbon fiber was used extensively, and the components were almost all designed, built, and tested by students with industry and academic mentorship. The eVe project was initiated in mid-2012, and the car competed in the 2013 World Solar Challenge, taking class line honours. It subsequently set a Fédération Internationale de l’Automobile land speed record in 2014 for the fastest average speed of an electric vehicle over 500 km; it is now the team’s intent to develop the car to road-legal status.

Teijin's advanced carbon fiber technology used to build a car for the World Solar Challenge

The biennial World Solar Challenge is the world's biggest solar car race which covers 3000 km across Australia from Darwin to Adelaide. OWL, an advanced solar-powered car developed by Kogakuin University using Teijin's carbon fiber reinforced plastic (CFRP) for its chassis and body structure, participated in the race from Japan and finished in second place.

Designing, Building of Solar Race Car for the World Solar Challenge (Phase I)

The purpose of this project is to design and build a solar race car for the world solar challenge. Three main goals were targeted for the competition: lightweight, aerodynamics, and efficiency. The renewable energy is becoming an alternative source for the fossil fuel. Solar energy in particular is abundant all year round within the Kingdome of Saudi Arabia. It is vital for the whole community to utilize this free energy into many areas such as power generation and building of solar cars. As many studies pointed out that the consumption of oil within the Kingdome is an alarming four million barrel per day. Most of it goes to generate electricity and gasoline for the cars. The car speed initially was tested at 70 km/hr and is expected to double for the world solar challenge race. The traveling distance covered will be about 3000 km. The body and chassis of the car were manufactured from fiber glass and aerospace aluminum material. Moreover, a system AC motors were designed, manufactured and assembled accompanied by gearbox, steering, axle, bearings, suspension system. Semi flexible solar panels were installed with power trackers and instrumentation. One driver was accommodated with a car net weight of 300 Kg.

Solar array design based on shadow analysis for increasing net energy collection in a competition vehicle

Photovoltaic (PV) applications such as in the architectural, automotive, and aerospace industries face design contradictions because they are expected to produce a lot of energy but are constrained by available area, surface shape, incident irradiance, shadows, and other aspects that have a negative influence on the energy produced by the solar panel. Solar competition vehicles are some of these challenging PV applications. The design of such solar arrays needs to consider efficiency evaluation in order to optimize space; it is difficult not to install solar modules in areas impacted by shadows. A design procedure for a solar array configuration based on shadow analysis for competition vehicles is presented. The principle is that shadows in moving objects can be simulated, since the vehicle, the earth and the sun are are moving in semipredictable patterns, thus net energy collection can be forecast. The case study presented is the solar array design of a vehicle that participated in the World Solar Challenge 2013. The obtained results illustrate how the employment of the procedure gives insights on important aspects to consider and also delivers qualitative and quantitative information for decision making. In addition, the experience in competition highlights some issues to be considered, modified, or improved in further vehicle designs.

Aerodynamic Analysis of the Preliminary Design of SURIAKAR 4 Using CFD

A four-wheel solar car, the SURIAKAR 4, was designed based on the revised regulations of the Challenger Class World Solar Challenge (2013). It is a four-wheel car with the front and back wheels enclosed in a wind cheating cover. The cockpit is located in such a way that it sits between the front and rear wheel, within the wheel cover on the right side of the car. This paper investigates the aerodynamic characteristics of the car, especially the drag and lift forces, and other forces and moments that determine the stability of the car using CFD package ANSYS Fluent. The model analysis was done with 2.23 million elements after a thorough grid independence study was conducted. The drag coefficient of SURIAKAR 4 is 0.1817. With a frontal area of 0.8934 m2 and at the design speed, the car requires 2132 W of power to overcome this aerodynamic drag. The results also showed that the airflow quality around the car is relatively well-behaved, with only a few turbulent flow points identified. This flow incurs drag penalty and thus have to be modified.

Aerodynamic design and development of the Sunswift IV solar racing car

The aerodynamic design and development of the University of New South Wales’ ultra-low-drag solar-electric Sunswift IV car is described, detailing the student-led design process from initial concept sketches to the completed vehicle. The body shape was established and refined over a period of six months in 2008–2009, almost entirely using computational fluid dynamics. The guiding philosophy was that predictable handling and drag minimisation in challenging, changing wind conditions of the type commonly seen during the World Solar Challenge across Australia was preferable to high performance only on ‘perfect’ days. The car won its class in the 2009 and 2011 World Solar Challenges, and holds the Guinness World Record for fastest solar-powered vehicle.

Optimal Design of a Solar Car Electrical System

This paper introduces the optimal electrical system design for a solar car, which complies with the regulations of World Solar Challenge 2013. The optimal design principles of high efficiency, light weight and high reliability were proposed. The solar energy collection system, energy storage system, drive system and electronic control system were all designed under the guidance of the principles. The structure and working principle of the solar car electrical system are also introduced. The experimental results show that the design goals have been achieved, and the performance of the system has also been verified.

The Body Design and Body Flow Passage Digital Simulation Analysis of the Solar Car

This paper designs the three-dimensional body modelling of a solar car prototype mainly according to the World Solar Challenge rules, and carries on the flow field digital simulation analysis. This paper analyzes the air resistance of the car body and adjusts to the body shape, and ultimately gets a model well accorded with air dynamics. This paper provides scientific theoretical basis for the design and manufacture of the solar car prototype.